TY - THES A1 - Klein, Detlef T1 - Dynamische kontrastmittelunterstützte Ultraschalluntersuchung fokaler Leberraumforderungen T1 - Quantitative Dynamic Contrast-enhanced Sonography of Hepatic Tumors N2 - Ziel: Versuch der Definition von Lebertumoren mit quantitativem dynamischem kontrast-verstärktem Ultraschall anhand der Beurteilung der Vaskularisation, wash-in, wash-out über einen definierten Zeitraum. Korrelation mit histologischen Befunden. Patienten und Methode: 42 Leberläsionen in 39 Patienten wurden mittels „Contrast Harmonic Imaging“ (CHI) über einen Zeitraum von 2 min nach einer Bolusinjektion von 10 ml Levovist® (300mg/ml, Schering AG, Berlin) untersucht. Die Untersuchungen wurden an einem Sonoline Elegra® (Siemens AG, Erlangen) mit einem frequenzvariablen 3,5 MHz Schallkopf durchgeführt. Das Kontrastmittelverhalten der Leberläsionen wurde durch eine speziell für Ultraschallkontrastmittel entwickelte Software (Axius™ ACQ (Siemens, Issaquah, WA)) quantifiziert. Repräsentative ROI wurden in das Zentrum der Läsion, über die gesamte Läsion, in normales Leberparenchym, sowie in repräsentative Lebergefäße (Leberarterie, Lebervene, Portalvene) gelegt. Die Kontrastmittelaufnahme der Leberläsionen wurde unterteilt in arteriell, portal-venös oder venös. Des Weiteren erfolgte eine Unterteilung in hypovaskular, isovaskular und hypervaskular im Vergleich zum normalen Leberparenchym. Zusätzlich wurde das Kontrastmittelverhalten innerhalb der Läsion beurteilt und unterteilt in zentrifugal, zentripetal, peripher und komplett. Alle Leberläsionen wurden vor und nach Kontrastmittelgabe von vier im Ultraschall, CT und MRT erfahrenen Radiologen ausgewertet ohne Kenntnis der Patientendaten oder des histologischen Ergebnis. Das Diagnosekriterium maligne wurde mittels einer ROC-Analyse ausgewertet. Zusätzlich wurden die durchschnittliche Sensitivität, Spezifität, sowie der positive und negative Vorhersagewert berechnet. Ergebnisse: Von 36 Raumforderungen lagen histologische Befunde vor. Histologisch ergaben sich 29 maligne Läsionen (HCC, n=11; CCC n=1; Lymphom, n=1, Metastasen, n=16) und 7 benigne Läsionen (Hämangiom, n=1; FNH, n=4, Adenom n=2). 4 FNH´s und 1 Hämangiom waren durch NUK, MRT und durch Langzeitkontrollen bestätigt. Die Auswertung der ROC-Analyse in Bezug auf das Kriterium maligne schwankte vor Kontrastmittelgabe zwischen 0,43 und 0,62 (Durchschnitt 0,57) und nach Kontrastmittelgabe zwischen 0,7 und 0,8 (Durchschnitt 0,75). Die durchschnittlichen Werte für die Sensitivität, Spezifität, negativer und positiver Vorhersagewert betrugen vor Kontrastmittelgabe 66%, 26%, 45% und 73% nach Kontrastmittelgabe 83%, 49%, 65% und 82%. Diskussion: Die Quantifizierung der verstärkten Gefäßdarstellung in Lebertumoren nach Bolus-Applikation eines Ultraschallkontrastmittels verbessert die Zuordnung zu einem malignen Prozess im Vergleich zum nativen Ultraschall. Um zuverlässigere Diagnosen stellen zu können ist eine Verbesserung der Auswertesoftware sowie die Berücksichtigung der neuen Generation von Ultraschallkontrastmitteln notwendig. N2 - OBJECTIVE. To define liver tumors using quantitative dynamic contrast-enhanced ultrasound compared to histological diagnosis, respectively long term follow ups. SUBJECTS AND METHODS. 42 focal liver lesions in 39 patients were examined by contrast harmonic imaging over a period of 2 min after bolus injection of 10 ml galactose-based contrast agent. Vascular enhancement was quantified by using a dedicated software that allowed to place representative regions of interest (ROI) in the centre of the lesion, in the complete lesions, in regular liver parenchyma, and in representative liver vessels (artery, vein, portal vein). Peak enhancement was judged to be either in the arterial, portal venous or in the late phase of liver perfusion. The lesion was described as hypovascular, isovascular and hypervascular compared to liver parenchyma. Contrast uptake was described as centrifugal or centripetal and peripheral or homogenous, respectively. Characterization of the lesions was performed unenhanced and after contrast by four independent specialists unaware of histology. Diagnosis of malignancy was evaluated by using a Receiver Operating Characteristic (ROC) analysis, also overall accuracy, average sensitivity, specificity, negative and positive predictive values were calculated. Interobserver agreement was defined by the Kappa statistics. RESULTS. Histologic examination revealed 29 malignant (hepatocellular carcinoma (HCC), n=11; cholangiocellular carcinoma (CCC), n=1; lymphoma, n=1; metastases, n=16), and 7 benign (hemangioma, n=1; focal nodular hyperplasia (FNH), n=4, adenoma, n=2) lesions. 6 benign lesions (hemangioma n=1; FNH n=5) were proved by long term follow up. ROC-Analysis regarding the diagnosis of malignancy showed values from 0.43 to 0.62 (mean 0.57) before and from 0.70 to 0.80 (mean 0.75) after contrast agent, respectively. The average values for sensitivity, specificity, accuracy, negative and positive predictive values were 66%, 26%, 62%, 45%, and 73% unenhanced and 83%, 49%, 73%, 65%, and 82% after contrast, respectively. The interobserver agreement was 0.54 and 0.65 for unenhanced and enhanced examinations, respectively. CONCLUSION. Quantitative dynamic contrast-enhanced sonography improves the diagnosis of malignancy in liver lesions. KW - Ultraschall KW - Levovist KW - Lebertumoren KW - Definition KW - Ultrasound KW - liver KW - US KW - contrast agents KW - Computer-aided diagnosis Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-15078 ER - TY - THES A1 - Klabouch [geb. Kleinbach], Stefanie T1 - Prädiktoren für die postinterventionelle Leberfunktion nach transarterieller Chemotherapie bei Patienten und Patientinnen mit hepatozellulärem Karzinom T1 - Predictors of postinterventional liver function after transarterial chemoembolization in patients with hepatocellular carcinoma N2 - Hintergrund: Die transarterielle Chemoembolisation (TACE) stellt eine Erstlinientherapie bei nicht resezierbarem HCC im intermediären Stadium (BCLC B) dar. TACE induziert einen zytotoxischen und ischämischen Gewebeeffekt, der möglicherweise zu einer Leberfunktionsstörung führt. Der 13C-Methacetin-Atemtest (MBT) ist ein nichtinvasiver CYP1A2-Funktionstest zur Beurteilung der funktionellen Leberzellmasse. Ziel dieser prospektiven Studie war es, die Auswirkung der konventionellen TACE auf die hepatozelluläre Reserve, gemessen mittels 13C-MBT, statischen Leberfunktionstests und entzündlichen Parametern bewerten zu können. Methoden & Ergebnisse: 27 Patient*innen mit nicht resezierbarem HCC (BCLC B, Child Pugh A) erhielten vor (d0), 24 Stunden (d1) und 72 Stunden (d3) nach 41 cTACE-Verfahren einen MBT. Das hepatische Lipiodol®-Verteilungsvolumen wurde aus CT-Daten berechnet. Statische Leberfunktionstests, entzündliche Parameter und klinische Ereignisse wurden an d0-3 analysiert. Es zeigte sich eine deutliche Verringerung der CYP1A2-Funktion nach cTACE an d1 und d3, was hauptsächlich durch die Entzündungsreaktion (CRP) und hepatozelluläre Schadensmarker (AST) und nur in geringem Maße durch das embolisierte Lebervolumen zu erklären ist. Schlussfolgerung: Der MBT kann die kurzfristige Verringerung der Leberfunktionsreserve sensitiv abbilden und korreliert mit klinischen Komplikationen nach cTACE. Der MBT kann Anwendung in der frühen Identifizierung einer hepatischen Dysfunktion finden. N2 - Background: Transarterial Chemoembolization (TACE) is a standard therapy for unresectable HCC and is suggested as first line-therapy for intermediate stages (BCLC B). TACE induces a cytotoxic and ischemic tissue effect potentially leading to hepatic dysfunction. 13C-methacetin breath test (MBT) is a noninvasive CYP1A2 function test for the assessment of hepatic functional reserve. We aimed to assess by MBT the effect of conventional TACE on hepatic functional reserve, static functional and inflammatory parameters. Methods & Results: 27 patients with unresectable HCC (BCLC B, Child Pugh A) underwent MBT before (d0), 24h (d1) and 72h (d3) after 41 cTACE procedures. Hepatic Lipiodol® distribution volumes were calculated from CT data. Static liver function, inflammatory markers and clinical events were assessed at d0-3. A rapid and marked reduction of CYP1A2 function occurred on d1 and d3, mainly explained by the inflammatory response (CRP) and hepatocellular damage markers (AST) but to a minor extent by hepatic embolization volumes. Conclusion: MBT can sensitively monitor short-term reduction in hepatic functional reserve and correlates with clinical complications after cTACE. MBT might be useful in the early identification of patients with hepatic dysfunction. KW - Leberfunktion KW - Leberzellkrebs KW - Kohlenstoff-13-Exhalationstest KW - Leberzirrhose KW - Leberversagen KW - Transarterielle Chemoembolisation KW - 13C-Methacetin-Atemtest KW - Hepatozelluläres Karzinom KW - Mikrosomale Leberfunktion Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-237070 ER - TY - JOUR A1 - Kippnich, Maximilian A1 - Schorscher, Nora A1 - Kredel, Markus A1 - Markus, Christian A1 - Eden, Lars A1 - Gassenmaier, Tobias A1 - Lock, Johann A1 - Wurmb, Thomas T1 - Dual‑room twin‑CT scanner in multiple trauma care: first results after implementation in a level one trauma centre JF - European Journal of Trauma and Emergency Surgery N2 - Purpose The trauma centre of the Wuerzburg University Hospital has integrated a pioneering dual-room twin-CT scanner in a multiple trauma pathway. For concurrent treatment of two trauma patients, two carbon CT examination and intervention tables are positioned head to head with one sliding CT-Gantry in the middle. The focus of this study is the process of trauma care with the time to CT (tCT) and the time to operation (tOR) as quality indicator. Methods All patients with suspected multiple trauma, who required emergency surgery and who were initially diagnosed by the CT trauma protocol between 05/2018 and 12/2018 were included. Data relating to time spans (tCT and tOR), severity of injury and outcome was obtained. Results 110 of the 589 screened trauma patients had surgery immediately after finishing primary assessment in the ER. The ISS was 17 (9–34) (median and interquartile range, IQR). tCT was 15 (11–19) minutes (median and IQR) and tOR was 96.5 (75–119) minutes (median and IQR). In the first 30 days, seven patients died (6.4%) including two within the first 24 h (2%). There were two ICU days (1–6) (median and IQR) and one (0–1) (median and IQR) ventilator day. Conclusion The twin-CT technology is a fascinating tool to organize high-quality trauma care for two multiple trauma patients simultaneously KW - trauma centre KW - trauma management KW - resuscitation time KW - dual-room whole-body CT Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232390 SN - 1863-9933 ER - TY - JOUR A1 - Kippnich, Maximilian A1 - Duempert, Maximilian A1 - Schorscher, Nora A1 - Jordan, Martin C. A1 - Kunz, Andreas S. A1 - Meybohm, Patrick A1 - Wurmb, Thomas T1 - Simultaneous treatment of trauma patients in a dual room trauma suite with integrated movable sliding gantry CT system: an observational study JF - Scientific Reports N2 - The trauma center of the University Hospital Wuerzburg has developed an advanced trauma pathway based on a dual-room trauma suite with an integrated movable sliding gantry CT-system. This enables simultaneous CT-diagnostics and treatment of two trauma patients. The focus of this study was to investigate the quality of the concept based on defined outcome criteria in this specific setting (time from arrival to initiation of CT scan: tCT; time from arrival to initiation of emergency surgery: tES). We analyzed all trauma patients admitted to the hospital’s trauma suite from 1st May 2019 through 29th April 2020. Two subgroups were defined: trauma patients, who were treated without a second trauma patient present (group 1) and patients, who were treated simultaneously with another trauma patient (group 2). Simultaneous treatment was defined as parallel arrival within a period of 20 min. Of 423 included trauma patients, 46 patients (10.9%) were treated simultaneously. Car accidents were the predominant trauma mechanism in this group (19.6% vs. 47.8%, p < 0.05). Prehospital life-saving procedures were performed with comparable frequency in both groups (intubation 43.5% vs. 39%, p = 0.572); pleural drainage 3.2% vs. 2.2%, p = 0.708; cardiopulmonary resuscitation 5% vs. 2.2%, p = 0.387). At hospital admission, patients in group 2 suffered significantly more pain (E-problem according to Advanced Trauma Life Support principles©; 29.2% vs. 45.7%, p < 0.05). There were no significant differences in the clinical treatment (emergency procedures, vasopressor and coagulant therapy, and transfusion of red blood cells). tCT was 6 (4–10) minutes (median and IQR) in group 1 and 8 (5–15.5) minutes in group 2 (p = 0.280). tES was 90 (78–106) minutes in group 1 and 99 (97–108) minutes in group 2 (p = 0.081). The simultaneous treatment of two trauma patients in a dual-room trauma suite with an integrated movable sliding gantry CT-system requires a medical, organizational, and technical concept adapted to this special setting. Despite the oftentimes serious and life-threatening injuries, optimal diagnostic and therapeutic procedures can be guaranteed for two simultaneous trauma patients at an individual medical level in consistent quality. KW - dual-room trauma suite KW - movable sliding gantry KW - CT Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-299695 VL - 12 IS - 1 ER - TY - JOUR A1 - Jordan, Martin C. A1 - Jovic, Sebastian A1 - Gilbert, Fabian A1 - Kunz, Andreas A1 - Ertl, Maximilian A1 - Strobl, Ute A1 - Jakubietz, Rafael G. A1 - Jakubietz, Michael G. A1 - Meffert, Rainer H. A1 - Fuchs, Konrad F. T1 - Qualitätssteigerung der Abrechnungsprüfung durch Smartphone-basierte Fotodokumentation in der Unfall-, Hand-, und Plastischen Chirurgie JF - Der Unfallchirurg N2 - Hintergrund Die Fotodokumentation von offenen Frakturen, Wunden, Dekubitalulzera, Tumoren oder Infektionen ist ein wichtiger Bestandteil der digitalen Patientenakte. Bisher ist unklar, welchen Stellenwert diese Fotodokumentation bei der Abrechnungsprüfung durch den Medizinischen Dienst der Krankenkassen (MDK) hat. Fragestellung Kann eine Smartphone-basierte Fotodokumentation die Verteidigung von erlösrelevanten Diagnosen und Prozeduren sowie der Verweildauer verbessern? Material und Methoden Ausstattung der Mitarbeiter mit digitalen Endgeräten (Smartphone/Tablet) in den Bereichen Notaufnahme, Schockraum, OP, Sprechstunden sowie auf den Stationen. Retrospektive Auswertung der Abrechnungsprüfung im Jahr 2019 und Identifikation aller Fallbesprechungen, in denen die Fotodokumentation eine Erlösveränderung bewirkt hat. Ergebnisse Von insgesamt 372 Fallbesprechungen half die Fotodokumentation in 27 Fällen (7,2 %) zur Bestätigung eines Operationen- und Prozedurenschlüssels (OPS) (n = 5; 1,3 %), einer Hauptdiagnose (n = 10; 2,7 %), einer Nebendiagnose (n = 3; 0,8 %) oder der Krankenhausverweildauer (n = 9; 2,4 %). Pro oben genanntem Fall mit Fotodokumentation ergab sich eine durchschnittliche Erlössteigerung von 2119 €. Inklusive Aufwandpauschale für die Verhandlungen wurde somit ein Gesamtbetrag von 65.328 € verteidigt. Diskussion Der Einsatz einer Smartphone-basierten Fotodokumentation kann die Qualität der Dokumentation verbessern und Erlöseinbußen bei der Abrechnungsprüfung verhindern. Die Implementierung digitaler Endgeräte mit entsprechender Software ist ein wichtiger Teil des digitalen Strukturwandels in Kliniken. N2 - Background Photographic documentation of wounds, decubitus ulcers, tumors, open fractures and infections is an important part of digital patient files. It is unclear whether the photographic documentation has an effect on medical accounting with health insurance companies. Objective It was hypothesized that Smartphone-based systematic photographic documentation can improve the confirmation of proceeds-relevant diagnoses and procedures as well as the duration. Material and methods Staff in the emergency room, operating theater, outpatient clinic and on the wards were equipped with digital devices (Smartphone, tablet) including a photo-app. Medical accounting with the health insurance companies and identification of all case conferences in which the photographic documentation had effected a change in proceeds were analyzed for 2019 in a retrospective manner. Results Overall, 372 cases were discussed of which 27 cases were affected by the digital photographic documentation. Photographic documentation was used for clarification of the operative procedure (n = 5), primary diagnosis (n = 10), secondary diagnosis (n = 3), and length of hospitalization (n = 9). An average of 2119 € was negotiated and added per case affected by photographic documentation. Hereby, a level 1 trauma center gained an estimated 65,328 € in revenue. Discussion The use of Smartphone based photographic documentation can improve the overall quality of patient files and thus avoid loss of revenue. The implementation of digital devices with corresponding software is an important component of the digital structural change in hospitals. KW - Digitalisierung KW - Gesundheits-App KW - Künstliche Intelligenz KW - Plattform KW - Strukturwandel KW - artificial intelligence KW - database KW - digital transformation KW - photo app KW - surgery Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232415 SN - 0177-5537 VL - 124 ER - TY - JOUR A1 - Jordan, Martin C. A1 - Bröer, David A1 - Fischer, Christian A1 - Heilig, Philipp A1 - Gilbert, Fabian A1 - Hölscher-Doht, Stefanie A1 - Kalogirou, Charis A1 - Popp, Kevin A1 - Grunz, Jan-Peter A1 - Huflage, Henner A1 - Jakubietz, Rafael G. A1 - Ergün, Süleyman A1 - Meffert, Rainer H. T1 - Development and preclinical evaluation of a cable-clamp fixation device for a disrupted pubic symphysis JF - Communications Medicine N2 - Background Traumatic separation of the pubic symphysis can destabilize the pelvis and require surgical fixation to reduce symphyseal gapping. The traditional approach involves open reduction and the implantation of a steel symphyseal plate (SP) on the pubic bone to hold the reposition. Despite its widespread use, SP-fixation is often associated with implant failure caused by screw loosening or breakage. Methods To address the need for a more reliable surgical intervention, we developed and tested two titanium cable-clamp implants. The cable served as tensioning device while the clamp secured the cable to the bone. The first implant design included a steel cable anterior to the pubic symphysis to simplify its placement outside the pelvis, and the second design included a cable encircling the pubic symphysis to stabilize the anterior pelvic ring. Using highly reproducible synthetic bone models and a limited number of cadaver specimens, we performed a comprehensive biomechanical study of implant stability and evaluated surgical feasibility. Results We were able to demonstrate that the cable-clamp implants provide stability equivalent to that of a traditional SP-fixation but without the same risks of implant failure. We also provide detailed ex vivo evaluations of the safety and feasibility of a trans-obturator surgical approach required for those kind of fixation. Conclusion We propose that the developed cable-clamp fixation devices may be of clinical value in treating pubic symphysis separation. KW - pubic symphysis KW - cable-clamp implants KW - SP-fixation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-299800 VL - 2 IS - 1 ER - TY - THES A1 - Johnson, Thorsten T1 - Entwicklung und Etablierung einer quantitativen Auswertemethode zur Beurteilung des Kontraktionsablaufs des Herzens (Tagging) T1 - Development and Establishment of a Quantitative Analysis for the Evaluation of Cardiac Motion from Tagged MR Images N2 - Ziel dieser Arbeit war es, verschiedene Parameter der linksventrikulären Wandbewegung aus MR-tagging-Aufnahmen quantitativ zu analysieren. Die Auswertemethode sollte angewendet werden, um den physiologischen Kontraktionsablauf zu charakterisieren und pathophysiologische Veränderungen zu erfassen. Die tagging-Untersuchung wurde in einer basisnahen, mittventrikulären und einer apikalen Schicht des linken Ventrikels durchgeführt. Für die automatische Quantifizierung von Rotation, Kontraktion und Umfangsverkürzung wurde eine geeignete Software erstellt. Die Methode wurde bei 8 gesunden Probanden, 13 Patienten mit Aortenstenose vor und 1 Jahr nach Klappenersatz und 10 Patienten mit Myokardinfarkt vor und nach Revaskularisation angewendet. Die entwickelte Software gestattet die Quantifizierung der linksventrikulären Wandfunktion über die Bestimmung von Rotation, Kontraktion und Umfangsverkürzung. Bei den Probanden zeigte sich eine Wringbewegung mit gegenläufiger Rotation der Herzbasis zur Herzspitze. Vor Klappenersatz zeigten die Patienten mit Aortenstenose eine signifikant verstärkte apikale Rotation und Torsion. 1 Jahr postoperativ hatte sich die Torsion normalisiert. Bei den Patienten mit Myokardinfarkt zeigte sich nach Revaskularisierung eine Zunahme der Umfangsverkürzung im Infarktareal. Die Quantifizierung der linksventrikulären Wandbewegung mit MR-tagging-Aufnahmen ermöglicht die Charakterisierung und Verlaufsbeobachtungen von Veränderungen der linksventrikulären Wandfunktion bei verschiedenen Herzerkrankungen. N2 - The purpose of this work was to establish a quantification of different parameters of left ventricular wall motion from tagged MR images. This evaluation method was to be applied to characterize the physiological contraction cycle and to determine pathophysiological changes. Myocardial tagging was performed at a basal, a mid-ventricular and an apical level of the left ventricle. A suitable software was programmed for the automatic quantification of rotation, contraction and circumferential shortening. The evaluation method was used in 8 healthy volunteers, 13 patients suffering from aortic stenosis before and 1 year after surgery and in 10 patients with myocardial infarction before and after revascularization. The software allows the quantification of left ventricular wall motion by assessment of rotation, contraction and circumferential shortening. In the healthy volunteers, there was a wrining motion with opposite rotation of base and apex of the heart. Before valve replacement, patients with aortic stenosis showed significantly increased apical rotation and torsion. 1 year after surgery, left-ventricular torsion had normalized. In patients with myocardial infarction, circumferential shortening increased after revascularization. The quantification of left ventricular wall motion using tagged MR images allows to characterize and follow-up changes of left ventricular wall motion in various diseases of the heart. KW - MRT KW - Herz KW - Aortenstenose KW - Tagging KW - MRI KW - heart KW - aortic stenosis KW - tagging Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-8897 ER - TY - THES A1 - Johnson, Alexandra Kirsten T1 - Perfusions-Computertomographie und transkranielle Dopplersonographie in der Evaluation von Vasospasmen nach aneurysmatischer Subarachnoidalblutung T1 - Perfusion-Computertomography and transcranial dopplersonography in the evaluation of vasospasm after aneurismal subarachnoid hemorrhage N2 - Die vorliegende Studie vergleicht die beiden diagnostischen Verfahren PCT und TCD zur Erfassung von Vasospasmen bei aneurysmatischer SAB. Durch den Einsatz des PCT gewinnt man bei Patienten mit SAB wichtige zusنtzliche Informationen, die für die weitere Diagnostik und Therapieplanung auكerordentlich hilfreich sind. Im Einzelnen finden sich folgende Ergebnisse: 1. Das Perfusions-CT zeigt eine Sensitivitنt von 0,61, eine Spezifitنt von 0, 71 und einen prنdiktiven Wert des positiven Tests von 0,53. TTP hat eine hohe Sensitivitنt von 0,61; CBV ist hِchst spezifisch (Sp 0, 98). 2. Die TCD zeigt nur eine mنكige Sensitivitنt (0,48) und Spezifitنt (0,62). 3. Bei zusنtzlicher Durchführung der TCD zur PCT-Untersuchung steigt die Sensitivitنt auf 0,73 an, was sich jedoch auf Kosten der Spezifitنt (0,48) und des prنdiktiven Werts des positiven Tests (0,42) auswirkt. 4. Die TCD-Untersuchung detektiert trotz tنglicher Durchführung Vasospasmen nicht früher als die PCT-Untersuchung. Dies wurde mittels des Chiquadrattests (Chiquadrat von 0,46) verdeutlicht. 5. PCT ist ein praktikables Verfahren, das Anhalt für weitere diagnostische und therapeutische Maكnahmen gibt. N2 - This study compares the two diagnostic methodes PCT and TCD for the verfication of vasospasms after aneurismal subarachnoid hemorrhage. With the PCT one can gain further information, important for further diagnostic and therapeutic planning. The Perfusion-CT has a high sensitivity of 0,61 and specifity of 0,71. The parameter TTP has the highest specifity of 0,98. In comparision shows the TCD only a moderate sensitivity and specifity. Perfusion-CT is a comming method which shows the presence of vasospasms at a very early stage. By using Perfusions-CT in combination with TCD, the predictability of vasospasm-induced-infarction is even higher. KW - Perfusionscomputertomographie KW - Vasospasmen KW - Subarachnoidalblutung KW - Aneurysma KW - Dopplersonographie KW - Perfusions-CT KW - Vasospasm KW - subarachnoid hemorrhage KW - transcranial dopplersonography Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-17853 ER - TY - JOUR A1 - Janssen, Jan P. A1 - Hoffmann, Jan V. A1 - Kanno, Takayuki A1 - Nose, Naoko A1 - Grunz, Jan-Peter A1 - Onoguchi, Masahisa A1 - Chen, Xinyu A1 - Lapa, Constantin A1 - Buck, Andreas K. A1 - Higuchi, Takahiro T1 - Capabilities of multi-pinhole SPECT with two stationary detectors for in vivo rat imaging JF - Scientific Reports N2 - We aimed to investigate the image quality of the U-SPECT5/CT E-Class a micro single-photon emission computed tomography (SPECT) system with two large stationary detectors for visualization of rat hearts and bones using clinically available \(^{99m}\)Tc-labelled tracers. Sensitivity, spatial resolution, uniformity and contrast-to-noise ratio (CNR) of the small-animal SPECT scanner were investigated in phantom studies using an ultra-high-resolution rat and mouse multi-pinhole collimator (UHR-RM). Point source, hot-rod, and uniform phantoms with \(^{99m}\)Tc-solution were scanned for high-count performance assessment and count levels equal to animal scans, respectively. Reconstruction was performed using the similarity-regulated ordered-subsets expectation maximization (SROSEM) algorithm with Gaussian smoothing. Rats were injected with similar to 100 MBq [\(^{99m}\)TcTc-MIBI or similar to 150 MBq [\(^{99m}\)Tc]Tc-HMDP and received multi-frame micro-SPECT imaging after tracer distribution. Animal scans were reconstructed for three different acquisition times and post-processed with different sized Gaussian filters. Following reconstruction, CNR was calculated and image quality evaluated by three independent readers on a five-point scale from 1="very poor" to 5="very good". Point source sensitivity was 567 cps/MBq and radioactive rods as small as 1.2 mm were resolved with the UHR-RM collimator. Collimator-dependent uniformity was 55.5%. Phantom CNR improved with increasing rod size, filter size and activity concentration. Left ventricle and bone structures were successfully visualized in rat experiments. Image quality was strongly affected by the extent of post-filtering, whereas scan time did not have substantial influence on visual assessment. Good image quality was achieved for resolution range greater than 1.8 mm in bone and 2.8 mm in heart. The recently introduced small animal SPECT system with two stationary detectors and UHR-RM collimator is capable to provide excellent image quality in heart and bone scans in a rat using standardized reconstruction parameters and appropriate post-filtering. However, there are still challenges in achieving maximum system resolution in the sub-millimeter range with in vivo settings under limited injection dose and acquisition time. KW - small animal SPECT KW - HMDP hydroxymethylene diphosphonate KW - skeletal KW - quality KW - scanner Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230616 VL - 10 ER - TY - THES A1 - Hümmer, Christian Andreas T1 - Die Wertigkeit der 1H- und 31P- Spektroskopie bei Rotatorenmanschettenrupturen T1 - Value of 1H- and 31P- MRI spectroscopy of rotator cuff tears N2 - In vielen Veröffentlichungen ist die Atrophie und die fettige Infiltration der Rotatorenmanschette als wichtiger Prädiktor für den Outcome nach Rekonstruktionen der Rotatorenmanschette belegt worden, insofern, als dass eine fettige Infiltration eine erhöhte Re-Rupturrate bedingt. Der intramuskuläre Fettgehalt wurde bisher mittels einer subjektiven, semiquantitativen Methode, die sich an einer morphologischen CT-Klassifikation orientierte, bestimmt. Durch die in der vorliegenden Arbeit verwendete nichtinvasive 2D-SPLASH Methode ist es möglich, den Verfettungsgrad der Rotatorenmanschettenmuskulatur in einer beliebigen ROI (Region Of Interest) im Rahmen einer Atrophie quantitativ zu bestimmen. Dazu wurden insgesamt 20 Patienten (weiblich/männlich: 7/13, Durchschnittsalter 57,5 ), die unter einem subakromialen Schmerzsyndrom litten, vor der operativen Rekonstruktion der Rotatorenmanschette einer MR-Untersuchung (1,5 T MR Tomograph, Siemens Vision Pro, Siemens AG Erlangen) unterzogen. Die hohe Validität dieser Messmethode ist durch die hochsignifikante Korrelation mit den Phantomuntersuchungen belegt worden. Als weiteres konnte gezeigt werden, dass die fettige Infiltration (bestimmt durch die 2D-SPLASH Methode) nur mäßig mit der mit Hilfe der Quer- und Längsschnittmessungen (cross-sectional areas) bestimmten Muskelatrophie des M. supraspinatus korreliert. Es konnte jedoch ein statistisch gesicherter Zusammenhang zwischen der intramuskulären Verfettung und dem Rupturausmaß belegt werden Zusammenfassend scheint die Entwicklung von Atrophie und fettiger Infiltration der an der Rotatorenmanschette beteiligten Muskeln ein multifaktorielles Geschehen zu sein, an dem eine muskelspezifische Komponente, die Anamnesedauer, die Defektgröße sowie eine Inaktivitäts- und neuromuskuläre Komponente beteiligt sind. Die 31P-MR-Spektroskopie stellt die einzige nichtinvasive Methode dar, mit der der Energiestoffwechsel der Muskulatur in-vivo beurteilt werden kann. In der vorliegenden Arbeit konnten mit Hilfe der 31P-MR-Spektroskopie die Verhältnisse der energiereichen Phosphate, vor allem das Verhältnis zwischen PCr zu ATP, bestimmt werden. Ein signifikanter Unterschied zu einem gesunden Vergleichskollektiv konnte nicht belegt werden. Dabei bleibt fraglich, ob es überhaupt zu einer Veränderung des Energie-stoffwechsels der Rotatorenmanschettenmuskulatur im Rahmen einer Atrophie kommt, wie es bei mitochondrialen, kongenitalen, inflammatorischen und neuropathischen Myopathien nachgewiesen wurde. November 2004 N2 - In many studies it was shown, that fatty infiltration of rotator cuff muscles was the reason of a higher rate of re-ruptures of rotator cuff muscles. The objective of this dissertation is to quantify the fatty degeneration (infiltration) of rotator cuff muscles with a new spectroscopic FLASH (SPLASH) sequence. Before planned surgery (reconstruction or muscle transfer), 20 patients (13 men, 7 women; 35-75 years) with different stages of rotator cuff disease underwent an MR examination in a 1.5 T unit. The protocol consists of imaging sequences and a newly implemented SPLASH, which allows an exact quantification of the fat / water ratio with a high spatial resolution in an arbitrarily shaped region of interest (ROI). The percentages of fat in the rotator cuff muscles were determined. To determine statistically significant differences between the different stages of rotator cuff tear, a Kruskal-Wallis H test was used. Fatty infiltration of the supraspinatus muscle was correlated with cross-sectional area (CSA) measures (Bravais-Person). We found significant differences between different stages of rotator cuff disease, the fatty infiltration and the volume loss (determined by the occupation ratio) of the supraspinatus muscle. With the increasing extent of rotator cuff disease, fatty infiltration increases significantly, as does the volume loss of the supraspinatus muscle. Comparing fatty infiltration and the occupation ratio individually, there was only a moderate inverse correlation between fatty infiltration and the occupation ratio, with considerable variation of data. Fatty infiltration of the infraspinatus muscle occurred when the infraspinatus tendo was involved to a lesser extent. The SPLASH sequence allows exact quantification of fatty infiltration in an arbitrarily shaped ROI. The extent of atrophy and fatty infiltration correlates with the size of tear. Atrophy and fatty infiltration correlate only moderately and should be evaluated separately. The phosphorus-spectroscopy is a not invasive method to measure the situation of metabolism energy of muscles. In this dissertation the relation between PCr and ATP in rotator cuff muscles was measured by phosphorus-spectroscopy. Significant differences in comparison with healthy people were not found. Finally there is no evidence, if atrophy of muscles actually changes the situation of metabolism energy November 2004 KW - Rotatorenmanschettenruptur KW - Magnetresonanztomographie KW - Muskelatrophie KW - Muskelverfettung KW - Spektroskopie KW - rotator cuff tear KW - fatty infiltration KW - spectroscopic sequences KW - supraspinatus KW - atrophy of muscles Y1 - 2004 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-12659 ER - TY - THES A1 - Hülße, Birgit T1 - Sonographische Diagnostik der Appendizitis - Vergleich der fundamentalen Bildgebung und Harmonic Imaging bei histologisch gesicherter Appendizitis T1 - Diagnosis of Appendicitis Using Harmonic Ultrasound Imaging N2 - Einleitung: Harmonic Imaging ist eine neue Ultraschallmodalität mit hoher Orts- und Kontrastauflösung. Mehrere Vergleichsstudien bei Erwachsenen haben gezeigt, dass Harmonic Imaging der konventionellen (=fundamentalen) Ultraschallbildgebung bei verschiedenen Fragestellungen überlegen ist. Ziel dieser Studie war der Bildqualitätsvergleich von fundamentaler Technik und Harmonic Imaging bei Kindern und Jugendlichen mit histologisch gesicherter Appendizitis. Patienten und Methodik: Bei 50 Kindern (m:w=25:25, Altersdurchschnitt: 9,9 Jahre), die unter dem klinischen Verdacht auf Appendizitis operiert wurden, führten wir präoperativ eine Sonographie in fundamentaler und Harmonic Imaging (Tissue Harmonic Imaging-THI- Sonoline Elegra®, Siemens) Technik durch. Es wurde ein 7,5-MHz-Linear-Schallkopf verwendet, welcher in beiden Modalitäten zu bedienen war. Eine detaillierte und vergleichbare Darstellung des Unterbauchs, insbesondere der Appendixregion, wurde mit beiden Techniken durchgeführt. Die mittels eines standardisierten Auswertungsbogens gewonnenen Daten wurden miteinander verglichen, mit den histologischen Befunden korreliert und statistisch ausgewertet. Zusätzlich wurde die Bildqualität im Rahmen einer Paarauswertung (geblindete Bildpaare: THI-fundamental) anhand einer 10-stufigen Rating-Skala (1=sehr schlecht bis 10=hervorragend) beurteilt. Ergebnisse: Bei 43/50 (86%) Patienten lag histologisch eine Appendizitis vor. Die sonographisch gestellte Verdachtsdiagnose besaß eine Sensitivität von 98% und eine Spezifität von 94%. Bei 37/43 Patienten konnte die Appendix mittels fundamentaler Technik, bei 40/43 Patienten mittels THI direkt dargestellt werden. THI erwies sich als signifikant überlegen bei der Darstellung der Außenkontur, der Wandschichtung, des Schleimhautechos und des Lumeninhaltes (p<0,0001). Auch bei der Beurteilung der Umgebungsechogenität, von freier Flüssigkeit, sowie mesenterialer Lymphknoten bot das THI Verfahren eine überlegene Darstellbarkeit. Bei der Paarauswertung ergab sich für THI ein mittlerer Rang von 8,1 und für die fundamentale Bildgebung ein Rang von 6,3. Schlussfolgerung: Bei der sonographischen Diagnostik der Appendizitis zeigt die Technik des THI eine der fundamentalen signifikant überlegene Bildqualität. Wenn beide Methoden vorhanden sind, sollte bei der Frage nach einer Appendizitis die Harmonic Imaging Technik bevorzugt eingesetzt werden. N2 - Harmonic imaging (HI) is a new US modality with high contrast and spatial resolution. Aim of this study was to compare fundamental imaging (FI) and HI in the diagnosis of appendicitis. In 50 children (male:female, 25:25; mean age: 9.9 years) prior to an appendectomy US of the right lower quadrant was performed in both FI and HI (7.5 MHz linear). The images were compared with respect to delineation of surrounding, contour, wall and content of the appendix. Paired images were ranked based on their diagnostic quality. In 43/50 (86%) patients diagnosis of appendicitis was confirmed histologically (sensitivity 98%, specificity 94%). In 37/43 patients the appendix was depicted using FI. With HI this number was 40/43. HI was significantly better in delineating the contour, wall, mucosa and content of the appendix (p<0.0001). HI also excelled in demonstrating free fluid, mesenterial lymph nodes and surrounding echogenicity. The paired evaluation (1=very poor- 10=excellent) resulted in a mean score of 8.1 for HI and 6.3 for FI. HI of appendicitis provides images with significantly better quality than FI. When both imaging options are available harmonic imaging modality should be the preferred choice for scanning the appendix. KW - Appendizitis KW - Kinder KW - Sonographie KW - Ultraschall KW - Harmonic Imaging KW - appendicitis KW - ultrasound KW - children KW - harmonic imaging Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-14111 ER - TY - JOUR A1 - Huflage, Henner A1 - Kunz, Andreas Steven A1 - Hendel, Robin A1 - Kraft, Johannes A1 - Weick, Stefan A1 - Razinskas, Gary A1 - Sauer, Stephanie Tina A1 - Pennig, Lenhard A1 - Bley, Thorsten Alexander A1 - Grunz, Jan-Peter T1 - Obesity-related pitfalls of virtual versus true non-contrast imaging — an intraindividual comparison in 253 oncologic patients JF - Diagnostics N2 - Objectives: Dual-source dual-energy CT (DECT) facilitates reconstruction of virtual non-contrast images from contrast-enhanced scans within a limited field of view. This study evaluates the replacement of true non-contrast acquisition with virtual non-contrast reconstructions and investigates the limitations of dual-source DECT in obese patients. Materials and Methods: A total of 253 oncologic patients (153 women; age 64.5 ± 16.2 years; BMI 26.6 ± 5.1 kg/m\(^2\)) received both multi-phase single-energy CT (SECT) and DECT in sequential staging examinations with a third-generation dual-source scanner. Patients were allocated to one of three BMI clusters: non-obese: <25 kg/m\(^2\) (n = 110), pre-obese: 25–29.9 kg/m\(^2\) (n = 73), and obese: >30 kg/m\(^2\) (n = 70). Radiation dose and image quality were compared for each scan. DECT examinations were evaluated regarding liver coverage within the dual-energy field of view. Results: While arterial contrast phases in DECT were associated with a higher CTDI\(_{vol}\) than in SECT (11.1 vs. 8.1 mGy; p < 0.001), replacement of true with virtual non-contrast imaging resulted in a considerably lower overall dose-length product (312.6 vs. 475.3 mGy·cm; p < 0.001). The proportion of DLP variance predictable from patient BMI was substantial in DECT (R\(^2\) = 0.738) and SECT (R\(^2\) = 0.620); however, DLP of SECT showed a stronger increase in obese patients (p < 0.001). Incomplete coverage of the liver within the dual-energy field of view was most common in the obese subgroup (17.1%) compared with non-obese (0%) and pre-obese patients (4.1%). Conclusion: DECT facilitates a 30.8% dose reduction over SECT in abdominal oncologic staging examinations. Employing dual-source scanner architecture, the risk for incomplete liver coverage increases in obese patients. KW - dual-energy CT KW - dual-source CT KW - virtual non-contrast KW - radiation dose KW - spectral CT KW - obesity Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-313519 SN - 2075-4418 VL - 13 IS - 9 ER - TY - JOUR A1 - Huflage, Henner A1 - Karsten, Sebastian A1 - Kunz, Andreas Steven A1 - Conrads, Nora A1 - Jakubietz, Rafael Gregor A1 - Jakubietz, Michael Georg A1 - Pennig, Lenhard A1 - Goertz, Lukas A1 - Bley, Thorsten Alexander A1 - Schmitt, Rainer A1 - Grunz, Jan-Peter T1 - Improved diagnostic accuracy for ulnar-sided TFCC lesions with radial reformation of 3D sequences in wrist MR arthrography JF - European Radiology N2 - Objectives Triangular fibrocartilage complex (TFCC) injuries frequently cause ulnar-sided wrist pain and can induce distal radioulnar joint instability. With its complex three-dimensional structure, diagnosis of TFCC lesions remains a challenging task even in MR arthrograms. The aim of this study was to assess the added diagnostic value of radial reformatting of isotropic 3D MRI datasets compared to standard planes after direct arthrography of the wrist. Methods Ninety-three patients underwent wrist MRI after fluoroscopy-guided multi-compartment arthrography. Two radiologists collectively analyzed two datasets of each MR arthrogram for TFCC injuries, with one set containing standard reconstructions of a 3D thin-slice sequence in axial, coronal and sagittal orientation, while the other set comprised an additional radial plane view with the rotating center positioned at the ulnar styloid. Surgical reports (whenever available) or radiological reports combined with clinical follow-up served as a standard of reference. In addition, diagnostic confidence and assessability of the central disc and ulnar-sided insertions were subjectively evaluated. Results Injuries of the articular disc, styloid and foveal ulnar attachment were present in 20 (23.7%), 10 (10.8%) and 9 (9.7%) patients. Additional radial planes increased diagnostic accuracy for lesions of the styloid (0.83 vs. 0.90; p = 0.016) and foveal (0.86 vs. 0.94; p = 0.039) insertion, whereas no improvement was identified for alterations of the central cartilage disc. Readers' confidence (p < 0.001) and assessability of the ulnar-sided insertions (p < 0.001) were superior with ancillary radial reformatting. Conclusions Access to the radial plane view of isotropic 3D sequences in MR arthrography improves diagnostic accuracy and confidence for ulnar-sided TFCC lesions. KW - joint instability KW - wrist KW - arthrography KW - magnetic resonance imaging KW - triangular fibrocartilage Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266512 SN - 1432-1084 VL - 31 IS - 12 ER - TY - THES A1 - Huckauf, Franziska Maria T1 - Wertigkeit eines Ganzkörper-Computertomographie-basierten Schockraumalgorithmus in der Primärdiagnostik polytraumatisierter Patienten am Beispiel des Würzburger Schockraums - Eine retrospektive Datenanalyse der Jahre 2005 bis 2008 T1 - Valency of a whole-body computed tomography-based algorithm in the primary diagnosis of polytrauma patients using the example of Wuerzburg Universitiy Hospital trauma suite - A retrospective data analysis of 2005 up to 2008 N2 - Die Frage nach der optimalen Diagnostik bei polytraumatisierten Patienten wird in der Literatur derzeit nicht abschließend beantwortet. Nichtsdestotrotz ist die Multislice-Computertomographie zur primären Diagnostik schwerstverletzter Patienten in regionalen sowie überregionalen Traumazentren unverzichtbar geworden. Seit 2004 ist im Würzburger Schockraum ein Computertomograph direkt im Schockraum verfügbar und die Ganzkörper-CT als primäres diagnostisches Mittel in den Schockraumalgorithmus integriert. Ziel dieser Datenerhebung ist es deshalb, die Wertigkeit dieses Konzeptes zu überprüfen. Zu diesem Zweck wurden retrospektiv Daten der Jahre 2005 bis einschließlich 2008 ausgewertet. Im Kollektiv enthalten sind 155 Patienten mit einem durchschnittlichen Alter von 39 Jahren und einem Männeranteil von 72,3%. Die Abbreviated Injury Scale ergab beim Würzburger Kollektiv verglichen mit den Daten der DGU einen hohen Anteil von Patienten mit schweren Verletzungen vor allem im Bereich von Abdomen (43,2% im Vergleich zu 22,8% bei der DGU), Thorax (75,5% vs. 58,0% bei der DGU), Extremitäten (65,8% vs. 38,0% bei der DGU) und Gesicht (21,9% vs. 4,6% bei der DGU). Beim Injury Severity Score wurde in vorliegender Datenerhebung ein Mittelwert von 37,8 Punkten berechnet, im Gegensatz zu durchschnittlich 24,5 Punkten bei den Daten der DGU. Ursache hierfür ist das Einschlusskriterium dieser Datenerhebung eines ISS ≥ 16, während bei der DGU nur 73% der Patienten eines ISS ≥ 16 hatten. 29% der Würzburger Patienten wurden entsprechend einem initialen GCS von ≤ 8 am Unfallort bewusstlos vorgefunden. Dieses Ergebnis deckt sich mit den gesamtdeutschen Daten, die im Jahresbericht 2008 der DGU veröffentlicht wurden. Die Standardisierte Mortalitätsrate, die mit Hilfe der RISC-Prognose und der Mortalitätsrate für dieses Kollektiv ermittelt wurde, lag bei 0,66. Das bedeutet, dass deutlich weniger Patienten verstorben sind als nach RISC-Prognose erwartet. Im Vergleich zu den Angaben der DGU, die für das Jahr 2007 das bisher beste Ergebnis mit einer SMR von 0,75 im Gesamtkollektiv berechneten, ein gutes Ergebnis. Die im direkten Vergleich höhere Letalität von 18,1% im Würzburger Kollektiv im Gegensatz zu 14% bei den gesamtdeutschen Daten der DGU lässt sich durch den deutlich höheren durchschnittlichen ISS begründen. Insgesamt wurde in den Jahren 2005 bis 2007 am Uniklinikum Würzburg eine Zunahme der Letalität polytraumatisierter Patienten innerhalb der ersten 24 Stunden nach dem Unfall beobachtet. Zunehmend weniger Patienten verstarben dagegen während des folgenden Krankenhausaufenthaltes. Bei der Gesamtletalität konnte eine Abnahme von 20,0% im Jahr 2005 auf 14,1% im Jahr 2007 verzeichnet werden. Die Berechnung der Diagnostikzeiten ergab eine durchschnittliche Gesamtuntersuchungsdauer von 51 Min (von der Ankunft des Patienten im Schockraum bis zum Ende der Datenrekonstruktion) und 29 Min von Beendigung des Scans bis zum Ende der Rekonstruktion. Durchschnittlich 22 Min wurden für den Zeitraum von Ankunft des Patienten bis zum Ende des Polytraumascans ermittelt, 7 Min betrug die reine Scanzeit. Die Daten decken sich mit den Berechnungen früherer Studien. Bei 30,3% der Würzburger Patienten wurden zusätzlich konventionelle Röntgenaufnahmen im Schockraum angefertigt. Der überwiegende Anteil der Aufnahmen, das heißt 34,0%, entfielen dabei auf Röntgenbilder des Thorax. Als Erklärung werden häufig notwendige Lagekontrollen nach Installation einer Thoraxdrainage oder eines zentralen Venenkatheters angeführt. Computertomographische Folgeuntersuchungen wurden bei insgesamt 72,9% der Patienten durchgeführt. Mit Abstand am häufigsten, in 47,6% der Fälle, wurden weitere Aufnahmen des Schädels angefertigt. Die Kontrolle der Kurzbefunde der Ganzkörper-CT ergab bei sechs der insgesamt 155 Patienten initial nicht diagnostizierte Läsionen. Die entsprechenden Verletzungen waren bei drei Patienten auch unter Kenntnis der intraoperativen Diagnosen in der retrospektiven Analyse nicht nachvollziehbar. Bei nur einem Patienten ergab sich eine reale therapeutische Relevanz, hier wurde eine Mandibulafraktur übersehen, die später einer operativen Versorgung bedurfte. Die Rate von initial sechs nicht entdeckten Verletzungen verdeutlicht die hohe Qualität der primären Diagnostik im Würzburger Schockraum. Die SMR als Kriterium der Versorgungsqualität bei der Behandlung polytraumatisierter Patienten ergab einen, im gesamtdeutschen Vergleich, hohen Standard. Zusammenfassend belegen unsere Daten den überlegenen Stellenwert eines Ganzkörper-Computertomographie-basierten Schockraumalgorithmus in der Primäversorgung polytraumatisierter Patienten am Beispiel des Würzburger Schockraums. N2 - Since 2004 whole-body multislice computed tomography is used in the trauma suite of Wuerzburg University Hospital as the primary diagnostic tool in patients with multiple trauma. The main goal of the dissertation is to examine the valency of that concept based on a retrospective data analysis of 2005 up to 2008 including 155 patients with severe trauma (injury severitiy score ≥ 16). The results confirm the outstanding significance of a whole-body computed tomography-based algorithm in the primary diagnosis of polytrauma patients using the example of Wuerzburg University Hospital trauma suite. KW - Polytrauma KW - Computertomographie KW - Computertomographie KW - Schockraumalgorithmus Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-109423 ER - TY - THES A1 - Hopfner, Witiko T1 - Die CT-gestützte Ganzkörperdiagnostik Schwerverletzter : Implementierung einer relationalen Datenbank und Untersuchungen zum Würzburger Schockraumalgorithmus T1 - The CT-supported complete body diagnostics of severely injuried persons. Implementation of a relational data base and investigations to the Würzburger "Schockraumalgorithmus" N2 - Untersuchungen von schwer verletzten Patienten, die in die zentrale Notaufnahme der Universität Würzburg eingeliefert wurden. Es wurde eine relationale Datenbank und entsprechende Auswertemechanismen implementiert, um die Patientendaten zu erfassen, zu strukturieren und auszuwerten. Weiterhin wurde anhand von CT Bildern polytraumatisierter Patienten der ISS berechnet und in die Datenbank eingetragen und entsprechend analysiert. Die Konformität der Verdachtsdiagnose Polytrauma, die anhand bestimmter Kriterien erfolgte, wurde mit dem ISS - Grenzwert 16 verglichen. N2 - Investigations of heavily hurt patients, who were supplied to the central emergency admission of the University of Würzburg. A relational data base and appropriate evaluation mechanisms were implemented, in order to seize the patient data to structure and evaluate. Further on the basis of CT pictures of polytraumata patients ISS was computed and registered into the data base and accordingly analyzed. The conformity of the suspicion diagnosis Polytrauma, which took place on certain criteria, became compared with ISS - limit value 16. KW - CT KW - ISS KW - Datenbank KW - Schockraumalgorithmus KW - Polytrauma KW - CT KW - ISS KW - data base Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-18254 ER - TY - THES A1 - Homola, György Ádám T1 - Functional and Microstructural MRI of the Human Brain Revealing a Cerebral Network Processing the Age of Faces T1 - Funktionelles und mikrostrukturelles MRT des menschlichen Gehirns detektiert ein zerebrales Netzwerk zur Verarbeitung des Alters von Gesichtern N2 - Although age is one of the most salient and fundamental aspects of human faces, its processing in the brain has not yet been studied by any neuroimaging experiment. Automatic assessment of temporal changes across faces is a prerequisite to identifying persons over their life-span, and age per se is of biological and social relevance. Using a combination of evocative face morphs controlled for global optical flow and functional magnetic resonance imaging (fMRI), we segregate two areas that process changes of facial age in both hemispheres. These areas extend beyond the previously established face-sensitive network and are centered on the posterior inferior temporal sulcus (pITS) and the posterior angular gyrus (pANG), an evolutionarily new formation of the human brain. Using probabilistic tractography and by calculating spatial cross-correlations as well as creating minimum intersection maps between activation and connectivity patterns we demonstrate a hitherto unrecognized link between structure and function in the human brain on the basis of cognitive age processing. According to our results, implicit age processing involves the inferior temporal sulci and is, at the same time, closely tied to quantity decoding by the presumed neural systems devoted to magnitudes in the human parietal lobes. The ventral portion of Wernicke’s largely forgotten perpendicular association fasciculus is shown not only to interconnect these two areas but to relate to their activations, i.e. to transmit age-relevant information. In particular, post-hoc age-rating competence is shown to be associated with high response levels in the left angular gyrus. Cortical activation patterns related to changes of facial age differ from those previously elicited by other fixed as well as changeable face aspects such as gender (used for comparison), ethnicity and identity as well as eye gaze or facial expressions. We argue that this may be due to the fact that individual changes of facial age occur ontogenetically, unlike the instant changes of gaze direction or expressive content in faces that can be “mirrored” and require constant cognitive monitoring to follow. Discussing the ample evidence for distinct representations of quantitative age as opposed to categorical gender varied over continuous androgyny levels, we suggest that particular face-sensitive regions interact with additional object-unselective quantification modules to obtain individual estimates of facial age. N2 - Obwohl das Alter eines der markantesten und grundlegendsten Aspekte menschlicher Gesichter darstellt, hat man die Verarbeitung im Gehirn noch nicht durch ein funktionell bildgebendes Verfahren untersucht und mit strukturellen Leitungsbahnen in Verbindung gebracht. Die automatische Bewertung der altersbedingten Veränderungen in Gesichtern ist eine Voraussetzung für die Identifizierung von Personen über ihre gesamte Lebenszeit, und das Lebensalter an sich ist von biologischer und sozialer Relevanz. In dieser Dissertation wird die funktionelle Kernspintomographie (fMRI) mit eindrucksvollen Gesichtsmorphs kombiniert, welche auf sichtbare Bewegung im gesamten Bild kontrolliert wurden. Hierdurch werden zwei Bereiche auf beiden Hemisphären isoliert, welche die Veränderungen des Alters von Gesichtern gemeinsam und automatisch verarbeiten. Diese Areale reichen über das zuvor etablierte gesichtssensible Netzwerk hinaus und zentrieren sich auf den hinteren inferio-temporalen Sulcus (pITS) und den hinteren angulären Gyrus (pANG), eine evolutionäre Neubildung des menschlichen Gehirns. Mit Hilfe der probabilistischen Traktographie diffusiongewichteter MRT-Daten und der Berechnung räumlicher Kreuzkorrelationen sowie der Erstellung von Minimum Intersection Maps zwischen Aktivierungs- und Konnektivitätsmustern wird ein bisher unerkannter Zusammenhang zwischen Struktur und Funktion des menschlichen Gehirns anhand der kognitiven Altersverarbeitung aufgezeigt. Unseren Ergebnissen zufolge wird der inferiore temporale Sulcus in die implizite Altersverarbeitung einbezogen und gleichzeitig eng mit der Mengendekodierung verknüpft, welche in den vermutlich Größenabschätzungen gewidmeten neuronalen Systemen im Scheitellappen des menschlichen Gehirns erfolgt. Es wird dargelegt, dass der ventrale Teil von Wernickes weitgehend vergessenem senkrecht verlaufendem Assoziationsbündels nicht nur diese beiden Bereiche miteinander verbindet, sondern auch mit ihren Aktivierungen in Beziehung steht, was die These stützt, dass altersrelevante Informationen tatsächlich über ihn übertragen werden. Bei der nachträglichen Alterseinschätzung der Gesichter zeigt sich, dass gutes Abschneiden der Versuchspersonen mit stärkeren Aktivierungen im linken angulären Gyrus einhergeht. Die kortikalen Aktivierungsmuster auf Änderungen des Gesichtsalters unterscheiden sich von jenen, die mit anderen wechselnden Gesichtsmerkmalen in Zusammenhang gebracht wurden, welche das Geschlecht (das zum Vergleich und zur Kontrolle herangezogen wurde), die Ethnizität und die personelle Identität sowie Blickrichtungen und Mimik betreffen. Es wird argumentiert, dass dies möglicherweise auf die Tatsache zurückzuführen ist, dass individuelle Änderungen des Gesichtsalters ontogenetisch auftreten, anders als beispielsweise die flüchtigen Wechsel von Blickrichtungen oder im Ausdruck in Gesichtern, welche vom Betrachter "gespiegelt" werden können und ständige Beobachtung erfordern, um kognitiv nachvollzogen werden zu können. Damit wird erstmals die eigene Art der Wahrnehmung und Verarbeitung des quantitativen Alters im direkten Gegensatz zu kategorischem Geschlecht belegt, welches über kontinuierliche Androgyniegrade variiert: Bestimmte gesichtssensible Regionen interagieren offenbar mit zusätzlichen nicht objekt-selektiven Quantifizierungsmodulen, um das Alter eines Gesichts individuell abzuschätzen. KW - Gesicht KW - Alter KW - NMR-Bildgebung KW - Gehirn KW - Informationsverarbeitung KW - Wernickes Assoziationsbündel KW - Diffusionsgewichtete Bildgebung KW - Morphing KW - Funktionelle NMR-Tomographie KW - Geschlecht KW - Nervenfaser KW - Korrelation KW - functional MRI KW - face morphing KW - facial age KW - facial gender KW - diffusion tractography KW - Wernicke's perpendicular fasciculus Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-56740 ER - TY - JOUR A1 - Hoffmann, Jan V. A1 - Janssen, Jan P. A1 - Kanno, Takayuki A1 - Shibutani, Takayuki A1 - Onoguchi, Masahisa A1 - Lapa, Constantin A1 - Grunz, Jan-Peter A1 - Buck, Andreas K. A1 - Higuchi, Takahiro T1 - Performance evaluation of fifth-generation ultra-high-resolution SPECT system with two stationary detectors and multi-pinhole imaging JF - EJNMMI Physics N2 - Background Small-animal single-photon emission computed tomography (SPECT) systems with multi-pinhole collimation and large stationary detectors have advantages compared to systems with moving small detectors. These systems benefit from less labour-intensive maintenance and quality control as fewer prone parts are moving, higher accuracy for focused scans and maintaining high resolution with increased sensitivity due to focused pinholes on the field of view. This study aims to investigate the performance of a novel ultra-high-resolution scanner with two-detector configuration (U-SPECT5-E) and to compare its image quality to a conventional micro-SPECT system with three stationary detectors (U-SPECT\(^+\)). Methods The new U-SPECT5-E with two stationary detectors was used for acquiring data with \(^{99m}\)Tc-filled point source, hot-rod and uniformity phantoms to analyse sensitivity, spatial resolution, uniformity and contrast-to-noise ratio (CNR). Three dedicated multi-pinhole mouse collimators with 75 pinholes each and 0.25-, 0.60- and 1.00-mm pinholes for extra ultra-high resolution (XUHR-M), general-purpose (GP-M) and ultra-high sensitivity (UHS-M) imaging were examined. For CNR analysis, four different activity ranges representing low- and high-count settings were investigated for all three collimators. The experiments for the performance assessment were repeated with the same GP-M collimator in the three-detector U-SPECT\(^+\) for comparison. Results Peak sensitivity was 237 cps/MBq (XUHR-M), 847 cps/MBq (GP-M), 2054 cps/MBq (UHS-M) for U-SPECT5-E and 1710 cps/MBq (GP-M) for U-SPECT\(^+\). In the visually analysed sections of the reconstructed mini Derenzo phantoms, rods as small as 0.35 mm (XUHR-M), 0.50 mm (GP-M) for the two-detector as well as the three-detector SPECT and 0.75 mm (UHS-M) were resolved. Uniformity for maximum resolution recorded 40.7% (XUHR-M), 29.1% (GP-M, U-SPECT5-E), 16.3% (GP-M, U-SPECT\(^+\)) and 23.0% (UHS-M), respectively. UHS-M reached highest CNR values for low-count images; for rods smaller than 0.45 mm, acceptable CNR was only achieved by XUHR-M. GP-M was superior for imaging rods sized from 0.60 to 1.50 mm for intermediate activity concentrations. U-SPECT5-E and U-SPECT+ both provided comparable CNR. Conclusions While uniformity and sensitivity are negatively affected by the absence of a third detector, the investigated U-SPECT5-E system with two stationary detectors delivers excellent spatial resolution and CNR comparable to the performance of an established three-detector-setup. KW - small-animal imaging KW - SPECT KW - mouse KW - ollimator KW - post-reconstruction filtering Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230361 VL - 7 ER - TY - JOUR A1 - Hock, Michael A1 - Terekhov, Maxim A1 - Stefanescu, Maria Roxana A1 - Lohr, David A1 - Herz, Stefan A1 - Reiter, Theresa A1 - Ankenbrand, Markus A1 - Kosmala, Aleksander A1 - Gassenmaier, Tobias A1 - Juchem, Christoph A1 - Schreiber, Laura Maria T1 - B\(_{0}\) shimming of the human heart at 7T JF - Magnetic Resonance in Medicine N2 - Purpose Inhomogeneities of the static magnetic B\(_{0}\) field are a major limiting factor in cardiac MRI at ultrahigh field (≥ 7T), as they result in signal loss and image distortions. Different magnetic susceptibilities of the myocardium and surrounding tissue in combination with cardiac motion lead to strong spatio‐temporal B\(_{0}\)‐field inhomogeneities, and their homogenization (B0 shimming) is a prerequisite. Limitations of state‐of‐the‐art shimming are described, regional B\(_{0}\) variations are measured, and a methodology for spherical harmonics shimming of the B\(_{0}\) field within the human myocardium is proposed. Methods The spatial B\(_{0}\)‐field distribution in the heart was analyzed as well as temporal B\(_{0}\)‐field variations in the myocardium over the cardiac cycle. Different shim region‐of‐interest selections were compared, and hardware limitations of spherical harmonics B\(_{0}\) shimming were evaluated by calibration‐based B0‐field modeling. The role of third‐order spherical harmonics terms was analyzed as well as potential benefits from cardiac phase–specific shimming. Results The strongest B\(_{0}\)‐field inhomogeneities were observed in localized spots within the left‐ventricular and right‐ventricular myocardium and varied between systolic and diastolic cardiac phases. An anatomy‐driven shim region‐of‐interest selection allowed for improved B\(_{0}\)‐field homogeneity compared with a standard shim region‐of‐interest cuboid. Third‐order spherical harmonics terms were demonstrated to be beneficial for shimming of these myocardial B\(_{0}\)‐field inhomogeneities. Initial results from the in vivo implementation of a potential shim strategy were obtained. Simulated cardiac phase–specific shimming was performed, and a shim term‐by‐term analysis revealed periodic variations of required currents. Conclusion Challenges in state‐of‐the‐art B\(_{0}\) shimming of the human heart at 7 T were described. Cardiac phase–specific shimming strategies were found to be superior to vendor‐supplied shimming. KW - 7 T KW - B KW - cardiac MRI KW - shimming KW - ultrahigh field Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-218096 VL - 85 IS - 1 SP - 182 EP - 196 ER - TY - THES A1 - Hilgarth, Markus T1 - Der aktuelle Stellenwert von Doppelkontrastpharyngographie und von Computertomographie bei der Detektion und bei der korrekten Stadienzuordnung von Tumoren des Oropharynx, Hypopharynx und des supraglottischen Larynx T1 - The current value of double contrast pharyngography and of computed tomography in detecting and correct staging of tumors of the oropharynx, hypopharynx and supraglottic larynx N2 - Retrospektive Analyse von Doppelkontrastpharyngographie (DkPh) und CT im Vergleich mit indirekter und direkter Laryngoskopie. Dazu wurden die Untersuchungsergebnisse von 151 Pat. mit Tumoren des Pharynx und des supraglottischen Larynx bezüglich Detektion und korrekter Stadienzuordnung nach dem TNM-System unter besonderer Berücksichtigung des subregionalen Befalls ausgewertet. Die DkPh stellt eine sinnvolle Ergänzung zur indirekten Laryngoskopie zur Tumordetektion dar, die Sensitivität wurde durch Kombination im Vergleich zu den einzelnen Verfahren signifikant verbessert. Zum Staging ist sie kein geeignetes Verfahren. Die CT Detektiert Tumoren zuverlässig. Bei der korrekten Stadienzuordnung liefert sie v.a. bzgl. Tiefeninfiltration wertvolle Zusatzinformationen. Fortgeschrittene Tumorstadien werden daher durch die CT signifikant besser dem korrekten T-Stadium zugeordnet als Tumor in frühen Tumorstadien. Durch Kombination von CT und direkter Laryngoskopie wurde die Sensitivität bzgl. einer korrekten Stadienzuornung im Vergleich zu den Einzelverfahren signifikant verbessert. N2 - The results of double contrast pharyngography (DCP) and CT where retrospectively analized and compared with the results of direct and indirect laryngoscopy. 151 patients with tumor of the oropharynx, hypopharynx and supraglottic larynx where included. DCP was a valuable technique in detecting tumors, espacially in the Hypopharynx. By combination of DCP and indirect laryngoscopy the sensitivity of detecting tumors was significantly improved. DCP was no suitable method in staging tumors. CT can reliable detect tumors of the pharynx and larynx. In correct staging CT staged T3/T4 tumors significantly correcter than T1/T2 tumors. Especially in detecting deep tumor infiltration CT can provide usefull additional information compared with the direct laryngoscopy.By combination the sensitivity in correct staging was significantly improved compared to the two single methods. KW - Tumor KW - Pharynx KW - Doppelkontrastpharyngographie KW - Computertomographie KW - Staging KW - Computed tomography KW - double-contrast pharyngography KW - tumor KW - pharynx Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-6099 ER - TY - THES A1 - Heuer, Anjana T1 - Aktive Gefäßverschlusssysteme in der interventionellen Radiologie: Sicherheit und Effektivität des neuartigen Doppelclip-basierten Celt ACD® Systems T1 - Active vascular closure devices in interventional radiology: safety and efficacy of a novel double-clip-based Celt ACD® system N2 - Mit steigender Nachfrage an minimal-invasiven Therapieoptionen wächst auch das Interesse an innovativen Alternativen im Bereich des arteriellen Gefäßverschlusses nach PVI. Ziel der vorliegenden Arbeit war es, die Effektivität und Sicherheit eines neu auf dem Markt befindlichen, Doppelclip-basierten aktiven VVS zu prüfen. Eine hohe technische Erfolgsrate von 98,8 % bei einer geringen Komplikationsrate von 3,6 % wurde verzeichnet. Bei Anwesenheit der Komorbiditäten Dm und CNI 5 zeigte sich eine signifikante Assoziation zu einem vermehrten Auftreten von Komplikationen. Ein nachgewiesener signifikanter Zusammenhang bestand zudem zwischen einem erhöhten Kalzifikationsgrad der Punktionsstelle bei Vorliegen einer pAVK und eines Dm. Eine erhöhte Gefäßrigidität aufgrund von Komorbiditäten und vaskulären Kalzifikationen, intrinsische Fremdkörperreaktionen, vasoregulatorische Reaktionen oder Produktversagen bieten hypothetische Erklärungsansätze für die einzelnen komplikativen Fälle. Die Nutzung des VVS in spezifischen, bisher nicht beschriebenen Situationen (Unterdimensionierung, Anwendung nach Gefäßpunktionen mit Zugangsschleusen bis 9F, antegrade Punktionsrichtung, anspruchsvolle Eingriffe multimorbider Patienten mit komplexem vaskulärem Status) erwies sich als suffizient. Zur Prävention schwerwiegender Komplikationen während zukünftiger Interventionen wurden die Empfehlung ausgesprochen, eine Durchleuchtungsaufnahme zur Lagekontrolle vor Implantation des proximalen Clips anzufertigen. Eine speziell für Gefäßverschlüsse nach antegrader Punktion konzipierte Zugangsschleuse könnte das Abknicken von Zugangsschleusen bei VVS Applikation verhindern. Zusammenfassend kann das untersuchte aktive VVS mit einzigartigem Wirkmechanismus und spezifischen Design als effektiv und sicher angesehen werden. N2 - The need of minimally invasive therapy options is constantly growing and so is the need for alternative options of vascular closure after peripheral vascular interventions. The aim of this thesis was to assess the efficacy and safety of the novel double-clip-based vascular closure device (VCD). The overall technical success rate was 98,8% with an overall low complication rate of 3,6 %. The comorbidities diabetes and chronical kidney disease proof to be significant risk factors for the appearance of complications. There was a significant association between an increased degree of calcification of the puncture site in the presence of peripheral artery disease and diabetes. Increased vascular rigidity due to comorbidities and vascular calcifications, intrinsic foreign body reactions, vasoregulatory reactions, or product failure offer hypothetical explanations for the individual complicative cases. The use of the VCD during previously not analyzed settings e.g. undersizing in relation to the introducer sheath, accesses of up to 8 or 9 Fr with a 7 Fr device, antegrade puncture and challenging patient collective, proofed to be sufficient. To prevent major complications during future application, it is recommended to check the position of the VCD fluoroscopically, before implantation of the proximal wing. A specially designed introducer sheath may be helpful to prevent kinking of the introducer sheath during VCD application in antegrad punctures. In conclusion, the novel VCD proved to be effective and safe. KW - Gefäßverschluss KW - Vascular closure devices KW - antegrade puncture KW - femoral access KW - access site complications Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300986 ER - TY - JOUR A1 - Herzberg, Moriz A1 - Dorn, Franziska A1 - Trumm, Christoph A1 - Kellert, Lars A1 - Tiedt, Steffen A1 - Feil, Katharina A1 - Küpper, Clemens A1 - Wollenweber, Frank A1 - Liebig, Thomas A1 - Zimmermann, Hanna T1 - Middle cerebral artery M2 thrombectomy: safety and technical considerations in the German Stroke Registry (GSR) JF - Journal of Clinical Medicine N2 - There is ongoing debate concerning the safety and efficacy of various mechanical thrombectomy (MT) approaches for M2 occlusions. We compared these for MT in M2 versus M1 occlusions. Subgroup analyses of different technical approaches within the M2 MT cohort were also performed. Patients were included from the German Stroke Registry (GSR), a multicenter registry of consecutive MT patients. Primary outcomes were reperfusion success events. Secondary outcomes were early clinical improvement (improvement in NIHSS score > 4) and independent survival at 90 days (mRS 0–2). Out of 3804 patients, 2689 presented with M1 (71%) and 1115 with isolated M2 occlusions (29%). The mean age was 76 (CI 65–82) and 77 (CI 66–83) years, respectively. Except for baseline NIHSS (15 (CI 10–18) vs. 11 (CI 6–16), p < 0.001) and ASPECTS (9 (CI 7–10) vs. 9 (CI 8–10, p < 0.001), baseline demographics were balanced. Apart from a more frequent use of dedicated small vessel stent retrievers (svSR) in M2 (17.4% vs. 3.0; p < 0.001), intraprocedural aspects were balanced. There was no difference in ICH at 24 h (11%; p = 1.0), adverse events (14.4% vs. 18.1%; p = 0.63), clinical improvement (62.5% vs. 61.4 %; p = 0.57), mortality (26.9% vs. 22.9%; p = 0.23). In M2 MT, conventional stent retriever (cSR) achieved higher rates of mTICI3 (54.0% vs. 37.7–42.0%; p < 0.001), requiring more MT-maneuvers (7, CI 2–8) vs. 2 (CI 2–7)/(CI 2–2); p < 0.001) and without impact on efficacy and outcome. Real-life MT in M2 can be performed with equal safety and efficacy as in M1 occlusions. Different recanalization techniques including the use of svSR did not result in significant differences regarding safety, efficacy and outcome. KW - mechanical thrombectomy KW - M2 KW - distal occlusion KW - endovascular therapy KW - aspiration KW - stent retriever KW - outcome Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-286052 SN - 2077-0383 VL - 11 IS - 15 ER - TY - JOUR A1 - Herzberg, Moritz A1 - Scherling, Korbinian A1 - Stahl, Robert A1 - Tiedt, Steffen A1 - Wollenweber, Frank A. A1 - Küpper, Clemens A1 - Feil, Katharina A1 - Forbrig, Robert A1 - Patzig, Maximilian A1 - Kellert, Lars A1 - Kunz, Wolfgang G. A1 - Reidler, Paul A1 - Zimmermann, Hanna A1 - Liebig, Thomas A1 - Dieterich, Marianne A1 - Dorn, Franziska T1 - Late Thrombectomy in Clinical Practice: Retrospective Application of DAWN/DEFUSE3 Criteria within the German Stroke Registry JF - Clinical Neuroradiology N2 - Background and Purpose To provide real-world data on outcome and procedural factors of late thrombectomy patients. Methods We retrospectively analyzed patients from the multicenter German Stroke Registry. The primary endpoint was clinical outcome on the modified Rankin scale (mRS) at 3 months. Trial-eligible patients and the subgroups were compared to the ineligible group. Secondary analyses included multivariate logistic regression to identify predictors of good outcome (mRS ≤ 2). Results Of 1917 patients who underwent thrombectomy, 208 (11%) were treated within a time window ≥ 6–24 h and met the baseline trial criteria. Of these, 27 patients (13%) were eligible for DAWN and 39 (19%) for DEFUSE3 and 156 patients were not eligible for DAWN or DEFUSE3 (75%), mainly because there was no perfusion imaging (62%; n = 129). Good outcome was not significantly higher in trial-ineligible (27%) than in trial-eligible (20%) patients (p = 0.343). Patients with large trial-ineligible CT perfusion imaging (CTP) lesions had significantly more hemorrhagic complications (33%) as well as unfavorable outcomes. Conclusion In clinical practice, the high number of patients with a good clinical outcome after endovascular therapy ≥ 6–24 h as in DAWN/DEFUSE3 could not be achieved. Similar outcomes are seen in patients selected for EVT ≥ 6 h based on factors other than CTP. Patients triaged without CTP showed trends for shorter arrival to reperfusion times and higher rates of independence. KW - late thrombectomy KW - stroke KW - endovascular therapy KW - outcome Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-264765 VL - 31 IS - 3 ER - TY - JOUR A1 - Herz, Stefan A1 - Stefanescu, Maria R. A1 - Lohr, David A1 - Vogel, Patrick A1 - Kosmala, Aleksander A1 - Terekhov, Maxim A1 - Weng, Andreas M. A1 - Grunz, Jan-Peter A1 - Bley, Thorsten A. A1 - Schreiber, Laura M. T1 - Effects of image homogeneity on stenosis visualization at 7 T in a coronary artery phantom study: With and without B1-shimming and parallel transmission JF - PloS One N2 - Background To investigate the effects of B\(_1\)-shimming and radiofrequency (RF) parallel transmission (pTX) on the visualization and quantification of the degree of stenosis in a coronary artery phantom using 7 Tesla (7 T) magnetic resonance imaging (MRI). Methods Stenosis phantoms with different grades of stenosis (0%, 20%, 40%, 60%, 80%, and 100%; 5 mm inner vessel diameter) were produced using 3D printing (clear resin). Phantoms were imaged with four different concentrations of diluted Gd-DOTA representing established arterial concentrations after intravenous injection in humans. Samples were centrally positioned in a thorax phantom of 30 cm diameter filled with a custom-made liquid featuring dielectric properties of muscle tissue. MRI was performed on a 7 T whole-body system. 2D-gradient-echo sequences were acquired with an 8-channel transmit 16-channel receive (8 Tx / 16 Rx) cardiac array prototype coil with and without pTX mode. Measurements were compared to those obtained with identical scan parameters using a commercially available 1 Tx / 16 Rx single transmit coil (sTX). To assess reproducibility, measurements (n = 15) were repeated at different horizontal angles with respect to the B0-field. Results B\(_1\)-shimming and pTX markedly improved flip angle homogeneity across the thorax phantom yielding a distinctly increased signal-to-noise ratio (SNR) averaged over a whole slice relative to non-manipulated RF fields. Images without B\(_1\)-shimming showed shading artifacts due to local B\(_1\)\(^+\)-field inhomogeneities, which hampered stenosis quantification in severe cases. In contrast, B\(_1\)-shimming and pTX provided superior image homogeneity. Compared with a conventional sTX coil higher grade stenoses (60% and 80%) were graded significantly (p<0.01) more precise. Mild to moderate grade stenoses did not show significant differences. Overall, SNR was distinctly higher with B\(_1\)-shimming and pTX than with the conventional sTX coil (inside the stenosis phantoms 14%, outside the phantoms 32%). Both full and half concentration (10.2 mM and 5.1 mM) of a conventional Gd-DOTA dose for humans were equally suitable for stenosis evaluation in this phantom study. Conclusions B\(_1\)-shimming and pTX at 7 T can distinctly improve image homogeneity and therefore provide considerably more accurate MR image analysis, which is beneficial for imaging of small vessel structures. KW - stenosis KW - magnetic resonance imaging KW - thorax KW - in vivo imaging KW - coronary arteries KW - image processing KW - 3D printing KW - signal to noise ratio Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300129 VL - 17 IS - 6 ER - TY - JOUR A1 - Hennes, Jan-Lucca A1 - Huflage, Henner A1 - Grunz, Jan-Peter A1 - Hartung, Viktor A1 - Augustin, Anne Marie A1 - Patzer, Theresa Sophie A1 - Pannenbecker, Pauline A1 - Petritsch, Bernhard A1 - Bley, Thorsten Alexander A1 - Gruschwitz, Philipp T1 - An intra-individual comparison of low-keV photon-counting CT versus energy-integrating-detector CT angiography of the aorta JF - Diagnostics N2 - This retrospective study aims to provide an intra-individual comparison of aortic CT angiographies (CTAs) using first-generation photon-counting-detector CT (PCD-CT) and third-generation energy-integrating-detector CT (EID-CT). High-pitch CTAs were performed with both scanners and equal contrast-agent protocols. EID-CT employed automatic tube voltage selection (90/100 kVp) with reference tube current of 434/350 mAs, whereas multi-energy PCD-CT scans were generated with fixed tube voltage (120 kVp), image quality level of 64, and reconstructed as 55 keV monoenergetic images. For image quality assessment, contrast-to-noise ratios (CNRs) were calculated, and subjective evaluation (overall quality, luminal contrast, vessel sharpness, blooming, and beam hardening) was performed independently by three radiologists. Fifty-seven patients (12 women, 45 men) were included with a median interval between examinations of 12.7 months (interquartile range 11.1 months). Using manufacturer-recommended scan protocols resulted in a substantially lower radiation dose in PCD-CT (size-specific dose estimate: 4.88 ± 0.48 versus 6.28 ± 0.50 mGy, p < 0.001), while CNR was approximately 50% higher (41.11 ± 8.68 versus 27.05 ± 6.73, p < 0.001). Overall image quality and luminal contrast were deemed superior in PCD-CT (p < 0.001). Notably, EID-CT allowed for comparable vessel sharpness (p = 0.439) and less pronounced blooming and beam hardening (p < 0.001). Inter-rater agreement was good to excellent (0.58–0.87). Concluding, aortic PCD-CTAs facilitate increased image quality with significantly lower radiation dose compared to EID-CTAs KW - CT angiography KW - aorta KW - photon-counting-detector CT KW - radiation dose reduction KW - spectral imaging Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-355568 SN - 2075-4418 VL - 13 IS - 24 ER - TY - JOUR A1 - Hendricks, Anne A1 - Lenschow, Christina A1 - Kroiss, Matthias A1 - Buck, Andreas A1 - Kickuth, Ralph A1 - Germer, Christoph-Thomas A1 - Schlegel, Nicolas T1 - Evaluation of diagnostic efficacy for localization of parathyroid adenoma in patients with primary hyperparathyroidism undergoing repeat surgery JF - Langenbeck's Archives of Surgery N2 - Purpose Repeat surgery in patients with primary hyperparathyroidism (pHPT) is associated with an increased risk of complications and failure. This stresses the need for optimized strategies to accurately localize a parathyroid adenoma before repeat surgery is performed. However, evidence on the extent of required diagnostics for a structured approach is sparse. Methods A retrospective single-center evaluation of 28 patients with an indication for surgery due to pHPT and previous thyroid or parathyroid surgery was performed. Diagnostic workup, surgical approach, and outcome in terms of complications and successful removement of parathyroid adenoma with biochemical cure were evaluated. Results Neck ultrasound, sestamibi scintigraphy, C11-methionine PET-CT, and selective parathyroid hormone venous sampling, but not MRI imaging, effectively detected the presence of a parathyroid adenoma with high positive predictive values. Biochemical cure was revealed by normalization of calcium and parathormone levels 24-48h after surgery and was achieved in 26/28 patients (92.9%) with an overall low rate of complications. Concordant localization by at least two diagnostic modalities enabled focused surgery with success rates of 100%, whereas inconclusive localization significantly increased the rate of bilateral explorations and significantly reduced the rate of biochemical cure to 80%. Conclusion These findings suggest that two concordant diagnostic modalities are sufficient to accurately localize parathyroid adenoma before repeat surgery for pHPT. In cases of poor localization, extended diagnostic procedures are warranted to enhance surgical success rates. We suggest an algorithm for better orientation when repeat surgery is intended in patients with pHPT. KW - Primary hyperparathyroidism (pHPT) KW - preoperative localization KW - repeat surgery KW - diagnostics KW - imaging Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-267520 SN - 1435-2451 VL - 406 IS - 5 ER - TY - THES A1 - Helbig, Christian T1 - Zeitaufgelöste MR-Angiographie der Nierenarterien - Morphologie und Perfusion T1 - Time-resolved MR angiography of the renal artery: morphology and perfusion N2 - Ziel dieser Arbeit war es nachzuweisen, dass mit der Kontrastmittel-unterstützten zeitaufgelösten MR-Angiographie neben der Detektion von Nierenarterienstenosen auch Veränderungen der Nierenperfusion bei Patienten mit unilateralen Nierenarterienstenosen zu erfassen sind. N2 - The purpose of this study was, to prove the hypothesis that renal artery stenosis and changes in renal perfusion can be detected with contrast-enhanced time-resolved MR angiography in a single examination. KW - MR-Tomographie KW - Magnetresonanzangiographie KW - Nierenarterien KW - Perfusion KW - Magnetic resonance (three dimensional) KW - magnetic resonance (vascular studies) KW - renal arteries KW - perfusion imaging Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-19963 ER - TY - JOUR A1 - Heinz, Tizian A1 - Meller, Felix A1 - Luetkens, Karsten Sebastian A1 - Horas, Konstantin A1 - Schäfer, Thomas A1 - Rudert, Maximilian A1 - Reppenhagen, Stephan A1 - Weißenberger, Manuel T1 - Can the MRI based AMADEUS score accurately assess pre-surgery chondral defect severity according to the ICRS arthroscopic classification system? JF - Journal of Experimental Orthopaedics N2 - Purpose The AMADEUS (Area Measurement And DEpth and Underlying Structures) scoring and grading system has been proposed for the MRI based evaluation of untreated focal chondral defects around the knee. The clinical practicability, its correlation with arthroscopically assessed grading systems (ICRS – International Cartilage Repair Society) and thereby its clinical value in terms of decision making and guiding prognosis was yet to determine. Methods From 2008 to 2019 a total of 89 individuals were indicated for high tibial valgus osteotomy (HTO) due to tibial varus deformity and concomitant chondral defects of the medial compartment of the knee. All patients received a preoperative MRI (1.5 Tesla or 3.0 Tesla) and pre-osteotomy diagnostic arthroscopy. Chondral defects of the medial compartment were scored and graded with the MRI based AMADEUS by three independent raters and compared to arthroscopic defect grading by the ICRS system. Interrater and intrarater reliability as well as correlation analysis with the ICRS classification system were assessed. Results Intraclass correlation coefficients for the various subscores of the AMADEUS showed an overall good to excellent interrater agreement (min: 0.26, max: 0.80). Intrarater agreement turned out to be substantially inferior (min: 0.08, max: 0.53). Spearman correlation revealed an overall moderate correlative association of the AMADEUS subscores with the ICRS classification system, apart from the defect area subscore. Sensitivity of the AMADEUS to accurately identify defect severity according to the ICRS was 0.7 (0.69 for 3.0 Tesla MRI, 0.67 for 1.5 Tesla MRI). The mean AMADEUS grade was 2.60 ± 0.81 and the mean ICRS score 2.90 ± 0.63. Conclusions Overall, the AMADEUS with all its subscores shows moderate correlation with the arthroscopic chondral grading system according to ICRS. This suggests that chondral defect grading by means of the MRI based AMADEUS is well capable of influencing and guiding treatment decisions. Interrater reliability shows overall good agreement. KW - MRI KW - knee KW - cartilage defect KW - grading system of chondral defects KW - AMADEUS KW - ICRS Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300781 SN - 2197-1153 VL - 9 IS - 1 ER - TY - JOUR A1 - Heinz, Tizian A1 - Meller, Felix A1 - Luetkens, Karsten Sebastian A1 - Anderson, Philip Mark A1 - Stratos, Ioannis A1 - Horas, Konstantin A1 - Rudert, Maximilian A1 - Reppenhagen, Stephan A1 - Weißenberger, Manuel T1 - The AMADEUS score is not a sufficient predictor for functional outcome after high tibial osteotomy JF - Journal of Experimental Orthopaedics N2 - Purpose The Area Measurement And Depth Underlying Structures (AMADEUS) classification system has been proposed as a valuable tool for magnetic resonance (MR)-based grading of preoperatively encountered chondral defects of the knee joint. However, the potential relationship of this novel score with clinical data was yet to determine. It was the primary intention of this study to assess the correlative relationship of the AMADEUS with patient reported outcome scores in patients undergoing medial open-wedge high tibial valgus osteotomy (HTO). Furthermore, the arthroscopic ICRS (International Cartilage Repair Society) grade evaluation was tested for correlation with the AMADEUS classification system. Methods This retrospective, monocentric study found a total of 70 individuals that were indicated for HTO due to degenerative chondral defects of the medial compartment between 2008 and 2019. A preoperative MR image as well as a pre-osteotomy diagnostic arthroscopy for ICRS grade evaluation was mandatory for all patients. The Knee Osteoarthritis Outcome Score (KOOS) including its five subscale scores (KOOS-ADL, KOOS-QOL, KOOS-Sports, KOOS-Pain, KOOS-Symptoms) was obtained preoperatively and at a mean follow-up of 41.2 ± 26.3 months. Preoperative chondral defects were evaluated using the AMADEUS classification system and the final AMADEUS scores were correlated with the pre- and postoperative KOOS subscale sores. Furthermore, arthroscopic ICRS defect severity was correlated with the AMADEUS classification system. Results There was a statistically significant correlation between the AMADEUS BME (bone marrow edema) subscore and the KOOS Symptoms subscore at the preoperative visit (r = 0.25, p = 0.04). No statistically significant monotonic association between the AMADEUS total score and the AMADEUS grade with pre- and postoperative KOOS subscale scores were found. Intraoperatively obtained ICRS grade did reveal a moderate correlative relation with the AMADEUS total score and the AMADEUS grade (r = 0.28, p = 0.02). Conclusions The novel AMADEUS classification system largely lacks correlative capacity with patient reported outcome measures in patients undergoing HTO. The MR tomographic appearance of bone marrow edema is the only parameter predictive of the clinical outcome at the preoperative visit. KW - cartilage KW - AMADEUS KW - KOOS KW - knee KW - high tibial osteotomy KW - chondral defect KW - osteoarthritis KW - PROM KW - correlation Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357765 VL - 10 ER - TY - JOUR A1 - Heidenreich, Julius F. A1 - Weng, Andreas M. A1 - Donhauser, Julian A1 - Greiser, Andreas A1 - Chow, Kelvin A1 - Nordbeck, Peter A1 - Bley, Thorsten A. A1 - Köstler, Herbert T1 - T1- and ECV-mapping in clinical routine at 3 T: differences between MOLLI, ShMOLLI and SASHA JF - BMC Medical Imaging N2 - Background T1 mapping sequences such as MOLLI, ShMOLLI and SASHA make use of different technical approaches, bearing strengths and weaknesses. It is well known that obtained T1 relaxation times differ between the sequence techniques as well as between different hardware. Yet, T1 quantification is a promising tool for myocardial tissue characterization, disregarding the absence of established reference values. The purpose of this study was to evaluate the feasibility of native and post-contrast T1 mapping methods as well as ECV maps and its diagnostic benefits in a clinical environment when scanning patients with various cardiac diseases at 3 T. Methods Native and post-contrast T1 mapping data acquired on a 3 T full-body scanner using the three pulse sequences 5(3)3 MOLLI, ShMOLLI and SASHA in 19 patients with clinical indication for contrast enhanced MRI were compared. We analyzed global and segmental T1 relaxation times as well as respective extracellular volumes and compared the emerged differences between the used pulse sequences. Results T1 times acquired with MOLLI and ShMOLLI exhibited systematic T1 deviation compared to SASHA. Myocardial MOLLI T1 times were 19% lower and ShMOLLI T1 times 25% lower compared to SASHA. Native blood T1 times from MOLLI were 13% lower than SASHA, while post-contrast MOLLI T1-times were only 5% lower. ECV values exhibited comparably biased estimation with MOLLI and ShMOLLI compared to SASHA in good agreement with results reported in literature. Pathology-suspect segments were clearly differentiated from remote myocardium with all three sequences. Conclusion Myocardial T1 mapping yields systematically biased pre- and post-contrast T1 times depending on the applied pulse sequence. Additionally calculating ECV attenuates this bias, making MOLLI, ShMOLLI and SASHA better comparable. Therefore, myocardial T1 mapping is a powerful clinical tool for classification of soft tissue abnormalities in spite of the absence of established reference values. KW - T1 mapping KW - MOLLI KW - ShMOLLI KW - SASHA KW - Extracellular volume KW - 3 T Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201999 VL - 19 ER - TY - INPR A1 - Heidenreich, Julius F. A1 - Gassenmaier, Tobias A1 - Ankenbrand, Markus J. A1 - Bley, Thorsten A. A1 - Wech, Tobias T1 - Self-configuring nnU-net pipeline enables fully automatic infarct segmentation in late enhancement MRI after myocardial infarction N2 - Purpose To fully automatically derive quantitative parameters from late gadolinium enhancement (LGE) cardiac MR (CMR) in patients with myocardial infarction and to investigate if phase sensitive or magnitude reconstructions or a combination of both results in best segmentation accuracy. Methods In this retrospective single center study, a convolutional neural network with a U-Net architecture with a self-configuring framework (“nnU-net”) was trained for segmentation of left ventricular myocardium and infarct zone in LGE-CMR. A database of 170 examinations from 78 patients with history of myocardial infarction was assembled. Separate fitting of the model was performed, using phase sensitive inversion recovery, the magnitude reconstruction or both contrasts as input channels. Manual labelling served as ground truth. In a subset of 10 patients, the performance of the trained models was evaluated and quantitatively compared by determination of the Sørensen-Dice similarity coefficient (DSC) and volumes of the infarct zone compared with the manual ground truth using Pearson’s r correlation and Bland-Altman analysis. Results The model achieved high similarity coefficients for myocardium and scar tissue. No significant difference was observed between using PSIR, magnitude reconstruction or both contrasts as input (PSIR and MAG; mean DSC: 0.83 ± 0.03 for myocardium and 0.72 ± 0.08 for scars). A strong correlation for volumes of infarct zone was observed between manual and model-based approach (r = 0.96), with a significant underestimation of the volumes obtained from the neural network. Conclusion The self-configuring nnU-net achieves predictions with strong agreement compared to manual segmentation, proving the potential as a promising tool to provide fully automatic quantitative evaluation of LGE-CMR. KW - Deep learning KW - CMR KW - Segmentation KW - Myocardial infarction KW - Scar KW - nnU-net Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-323418 UR - https://doi.org/10.1016/j.ejrad.2021.109817 ET - accepted version ER - TY - JOUR A1 - Hartrampf, Philipp E. A1 - Petritsch, Bernhard A1 - Buck, Andreas K. A1 - Serfling, Sebastian E. T1 - Pitfalls in PSMA-PET/CT: Intensive bone-marrow uptake in a case with polycythaemia vera JF - European Journal of Nuclear Medicine and Molecular Imaging N2 - No abstract available. KW - bone-marrow Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235608 SN - 1619-7070 VL - 48 ER - TY - THES A1 - Halla, Armin T1 - Materialdefekte von Stents und ihre klinischen Auswirkungen im Bereich der unteren Extremität T1 - Material defects of stents and their clinical relevance in the lower extremity N2 - Im Institut für Röntgendiagnostik der Universität Würzburg wurden in einem Zeitraum von bis zu 68 Monaten 168 Patienten mit PAVK der unteren Extremität mit einem oder mehreren Stents versorgt und anschließend regelmäßig kontrolliert. Insgesamt wurden 405 Stents implantiert. In den Nachkontrollen wurden die Stents mittels Röntgenzielaufnahmen in 2 Ebenen auf Frakturen sowie mit Hilfe der FKDS auf Restenosen oder Okklusionen untersucht. In der vorliegenden Studie wurden Ursachen für das Auftreten von Stentfrakturen ermittelt und ihre klinische Relevanz beurteilt. N2 - In the department of radiology of the University of Würzburg 168 patients with peripheral artery disease in the lower extremity, which were treated with one or more stents, were examined over a period of 68 months. Overall there were 405 stents implanted. In follow-up examinations these stents were screened for fractures using two-plane x-ray imaging. Color duplex sonography was applied to detect restenosis and occlusion-rates. The aim of our study was to identify possible causes for stent fractures and to evaluate their clinical relevance. KW - Stent KW - Stentfraktur KW - Stentfracture Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-46004 ER - TY - JOUR A1 - Habarta, Johanna A1 - Jordan, Martin A1 - Meffert, Rainer A1 - Huflage, Henner A1 - Schmalzl, Jonas T1 - Surgical management of a traumatic elbow dislocation with disruption of the brachial artery. Case report JF - Obere Extremität N2 - Background Dislocations of the elbow are the second most common dislocations of humeral joints following the shoulder. Besides numerous possible concomitant injuries of the collateral ligaments or the extensor or flexor apparatus, an accompanying disruption of the brachial artery is a rare occurrence. In the following, such a case is presented and discussed. Method A 70-year-old woman sustained a closed posterior elbow dislocation with accompanying disruption of the brachial artery due to a fall in a domestic environment. Pulselessness of the radial artery led to a computed tomography angiography being performed, which confirmed the diagnosis. Direct operative vascular reconstruction with a vein insert was carried out. Due to strong swelling of the soft tissue, other examinations of the elbow could not be performed initially. A redislocation a few days later led to an operative stabilization of the elbow joint. Results The final consultation 4 months postoperatively showed a stable, centered elbow joint and a normal perfusion of the affected arm. The elbow function was good with a range of motion of 0/0/110° of extension/flexion. Conclusion An elbow dislocation is a complex injury. An accurate clinical examination of possible concomitant injuries is important and should be repeated in the first few days after the occurrence. Vascular reconstruction should be performed immediately. In the case of persistent joint instability, an operative stabilization is indicated and may be supported by a hinged external fixator. N2 - Hintergrund Eine Luxation des Ellenbogens stellt die zweithäufigste Luxation des menschlichen Körpers dar. Neben verschiedenen möglichen Begleitverletzungen im Bereich des Kapsel-Band-Apparats und der Sehnenansätze ist eine Abrissverletzung der A. brachialis eine Seltenheit. Im Folgenden wird ein solcher Fall präsentiert und diskutiert. Methoden Eine 70 Jahre alte Frau stürzte im häuslichen Umfeld und erlitt eine geschlossene Luxation des linken Ellenbogens mit begleitendem Abriss der A. brachialis. Fehlende Pulse der A. radialis führten zur Zuverlegung und zur Anfertigung einer computertomographiegesteuerten Angiographie, welche die Diagnose bestätigte. Die operative Gefäßrekonstruktion mittels Veneninterponat erfolgte sofort. Aufgrund stark geschwollener Weichteilverhältnisse waren weitere Untersuchungen des Ellenbogengelenks zunächst nicht möglich. Ein Reluxationsereignis einige Tage nach dem Unfall veranlasste zu weiterführender Diagnostik und operativer Stabilisierung des Ellenbogens. Ergebnisse Die Nachuntersuchung 4 Monate postoperativ zeigte ein stabiles, zentriertes Ellenbogengelenk, eine regelrechte Durchblutung des betroffenen Arms sowie eine gute Ellenbogenfunktion mit einem Bewegungsausmaß von 0/0/110° Extension/Flexion. Schlussfolgerung Eine Luxation des Ellenbogens ist eine komplexe Verletzung. Eine sorgfältige klinische Untersuchung aller möglichen Begleitverletzungen ist wichtig und sollte in den ersten Tagen mehrmals wiederholt werden. Gefäßverletzungen sollten sofort operativ behandelt werden. Bei persistierenden Gelenkinstabilitäten und Reluxationstendenzen ist eine operative Stabilisierung des Gelenks durchzuführen, welche durch die Anlage eines Bewegungsfixateurs unterstützt werden kann. T2 - Chirurgische Versorgung einer traumatisch bedingten Ellenbogenluxation mit Riss der A. brachialis. Fallbericht KW - elbow joint KW - vascular reconstruction KW - orthopedic surgery KW - joint instability KW - hinged external fixator KW - Ellenbogengelenk KW - Vaskuläre Rekonstruktion KW - Orthopädische Chirurgie KW - Gelenkinstabilität KW - Bewegungsfixateur Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-323972 SN - 1862-6599 VL - 17 IS - 4 ER - TY - THES A1 - Gutberlet, Marcel T1 - K-Raum-Symmetrie und dichtegewichtete Bildgebung: Optimierung der Magnet-Resonanz-Bildgebung hinsichtlich Signal-zu-Rauschverhältnis, Abbildungsqualität und Messzeit T1 - K-space symmetry and density weighted imaging:Optimization of magnetic resonance imaging with regard to signal-to-noise ratio, image quality and acquisition time N2 - Die Magnet-Resonanz (MR)-Bildgebung ist mit vielfältigen Anwendungen ein nicht mehr wegzudenkendes Instrument der klinischen Diagnostik geworden. Dennoch führt die stark limitierte Messzeit häufig zu einer Einschränkung der erzielbaren räumlichen Auflösung und Abdeckung, einer Beschränkung des Signal-zu-Rauschverhältnis (Signal-to-Noise Ratio) (SNR) sowie einer Signalkontamination durch benachbartes Gewebe. Bereits bestehende Methoden zur Reduktion der Akquisitionszeit sind die partielle Fourier (PF)-Bildgebung und die parallele Bildgebung (PPA). Diese unterscheiden sich zum einen im Schema zur Unterabtastung des k-Raums und zum anderen in der verwendeten Information zur Rekonstruktion der fehlenden k-Raum-Daten aufgrund der beschleunigten Akquisition. Während in der PPA die unterschiedlichen Sensitivitäten einer Mehrkanal-Empfangsspule zur Bildrekonstruktion verwendet werden, basiert die PF-Bildgebung auf der Annahme einer langsamen Variation der Bildphase. Im ersten Abschnitt dieser Arbeit wurde das Konzept der Virtuellen Spulendekonvolutions (Virtual Coil Deconvolution) (VIDE)-Technik vorgestellt, das das gleiche Schema der Unterabtastung des k-Raums wie die konventionelle PPA verwendet, aber anstelle der Spulensensitivität die Bildphase als zusätzliche Information zur Herstellung der fehlenden Daten der beschleunigten Bildgebung verwendet. Zur Minimierung der Rekonstruktionsfehler und der Rauschverstärkung in der VIDE-Technik wurde ein optimiertes Akquisitionsschema entwickelt. Die Kombination der PPA und PF-Bildgebung zur Beschleunigung der MR-Bildgebung wird durch das unterschiedliche Unterabtastschema erschwert. Wie Blaimer et al. in ihrer Arbeit gezeigt haben, kann das Prinzip der VIDE-Technik auf Mehrkanal-Spulen übertragen werden, sodass mit dieser Methode die PPA und die PF-Bildgebung optimal vereint werden können. Dadurch kann die Rauschverstärkung aufgrund der Spulengeometrie ohne zusätzliche Messungen deutlich reduziert werden. Obwohl die Abtastung des k-Raums in der MR-Bildgebung sehr variabel gestaltet werden kann, wird bis heute nahezu ausschließlich die regelmäßige k-Raum-Abtastung in der klinischen Bildgebung verwendet. Der Grund hierfür liegt, neben der schnellen Rekonstruktion und der einfachen Gestaltung der Variation des Bild-Kontrasts, in der Robustheit gegen Artefakte. Allerdings führt die regelmäßige k-Raum-Abtastung zu einer hohen Signalkontamination. Die Optimierung der SRF durch nachträgliches Filtern führt jedoch zu einem SNR-Verlust. Die dichtegewichtete (DW-) Bildgebung ermöglicht die Reduktion der Signal-Kontamination bei optimalem SNR, führt aber zur einer Reduktion des effektiven Gesichtsfelds (FOV) oder einer Erhöhung der Messzeit. Letzteres kann durch eine Kombination der PPA und DW-Bildgebung umgangen werden. Der zweite Teil dieser Arbeit befasste sich mit neuen Aufnahme- und Rekonstruktionsstrategien für die DW-Bildgebung, die eine Erhöhung des FOVs auch ohne Einsatz der PPA erlauben. Durch eine Limitierung der minimalen k-Raum-Abtastdichte konnte durch eine geringfügige Reduktion des SNR-Vorteils der DW-Bildgebung gegenüber der kartesischen, gefilterten Bildgebung eine deutliche Verringerung der Artefakte aufgrund der Unterabtastung in der DW-Bildgebung erreicht werden. Eine asymmetrische Abtastung kann unter der Voraussetzung einer homogenen Bildphase das Aliasing zusätzlich reduzieren. Durch die Rekonstruktion der DW-Daten mit der Virtuelle Spulendekonvolution für die effektive DW-Bildgebung (VIDED)-Bildgebung konnten die Artefakte aufgrund der Unterabtastung eliminiert werden. In der 3d-Bildgebung konnte durch Anwendung der modifizierten DW-Bildgebung eine Steigerung des FOVs in Schichtrichtung ohne Messzeitverlängerung erreicht werden. Die nicht-kartesische k-Raum-Abtastung führt im Fall einer Unterabtastung zu deutlich geringeren, inkohärenten Aliasingartefakten im Vergleich zur kartesischen Abtastung. Durch ein alternierendes DW-Abtastschema wurde eine an die in der MR-Mammografie verwendete Spulengeometrie angepasste k-Raum-Abtastung entwickelt, das bei gleicher Messzeit die räumliche Auflösung, das SNR und das FOV erhöht. Im dritten Teil dieser Arbeit wurde die Verallgemeinerung der DW-Bildgebung auf signalgewichtete Sequenzen, d.h. Sequenzen mit Magnetisierungspräparation (Inversion Recovery (IR), Saturation Recovery (SR)) sowie Sequenzen mit einer Relaxation während der Datenaufnahme (Multi-Gradienten-Echo, Multi-Spin-Echo) vorgestellt, was eine Steigerung der Bildqualität bei optimalem SNR erlaubt. Die Methode wurde auf die SR-Sequenz angewendet und deren praktischer Nutzen wurde in der Herz-Perfusions-Bildgebung gezeigt. Durch die Verwendung der in dieser Arbeit vorgestellten Technik konnte eine Reduktion der Kontamination bei einem SNR-Gewinn von 16% im Vergleich zur konventionellen, kartesischen Abtastung bei gleicher Messzeit erreicht werden. N2 - Magnetic resonance (MR) imaging has become a powerful tool in clinical diagnostics. However, long acquisition times used in MR imaging limit the available signal-to-noise Ratio (SNR), spatial resolution and coverage and cause signal contamination from neighboring tissue. Two established methods used to reduce the scan time of MR imaging are partial parallel acquisition (PPA) and partial fourier (PF) imaging. These methods use different schemes to undersample k-space and use a different kind of information to reconstruct the missing data resulting from the accelerated acquisition. While in PPA the varying sensitivities of a multi-channel receiver coil are used in the image reconstruction, PF imaging is based on the assumption of a smoothly varying image phase. In the first section of this work, the concept of virtual coil deconvolution (VIDE) imaging is proposed. This method uses the identical acquisition scheme for the accelerated measurement of k-space as PPA. However, in contrast to PPA, VIDE imaging uses the image phase instead of the varying coil sensitivities to recover the missing data of the accelerated acquisition. Reconstruction errors and noise amplification of VIDE imaging were minimized by an optimized acquisition scheme. VIDE imaging allows an acceleration of MR imaging by a factor of two. The different sampling schemes used in PF imaging and PPA are disadvantageous for the combination of PF imaging and PPA to increase the acceleration of MRI. Blaimer, Gutberlet et al. showed that the concept of VIDE imaging can be extended to multi-channel receiver coils. This allows an optimal combination of PF imaging and PPA. The noise amplification caused by the coil geometry could be significantly decreased without lengthening the scan time. Although k-space can be measured in a variety of sampling schemes, almost exclusively a Cartesian trajectory is used in clinical imaging. Reasons are the fast and simple reconstruction, the robustness against artifacts and the well-defined contrast of Cartesian imaging. However, the Cartesian acquisition results in increased signal contamination. Post-processing filtering allows reduction of contamination but at the expense of SNR. Density weighted (DW) imaging allows optimization of the spatial response function (SRF) at maximum SNR but results in a reduced effective field of view (FOV) or a lengthening of the scan time. This disadvantage of DW imaging can be eliminated by the application of PPA. In the second section new acquisition and reconstruction methods were presented allowing an increase of the effective FOV in DW imaging even without the use of PPA. The limitation of the minimum sampling density in DW imaging resulted in a significant reduction of aliasing. Moderate filtering to correct the k-space weighting resulted in low reduction of the SNR gain in comparison to Cartesian imaging with the identical scan time. On condition of a homogeneous image phase, the aliasing can be additionally reduced by using an asymmetric DW sampling. Using virtual coil deconvolution for effective density weighted (VIDED) imaging for reconstruction, aliasing could be eliminated. By applying the developed DW method, the spatial coverage of 3D imaging was increased even without a lengthening of the scan time. In case of undersampling k-space, DW acquisition results in significantly reduced incoherent aliasing in comparison to Cartesian imaging. Alternating DW sampling revealed an optimized sampling scheme for the coil geometry used in MR-mammography. In experiments the effective FOV or the spatial resolution in slice direction could be increased significantly. In the third section the extension of DW imaging to signal-weighted sequences, i.e. sequences with magnetization preparation (inversion recovery or saturation recovery) or with relaxation between the acquired echoes (multigradient echo, multi-spin echo), was presented. The method provided increased image quality at optimum SNR in comparison to Cartesian imaging. By applying the new technique to SR-sequences, its practical use could be shown in myocardial perfusion imaging. The method presented in this work allowed an optimization of the SRF with an SNR gain of 16% compared to conventional Cartesian sampling at identical scan time. KW - Kernspintomografie KW - Paralleler Prozess KW - Messprozess KW - Dichtegewichtete Bildgebung KW - Parallele Bildgebung KW - VIDE KW - VIDED KW - density weighted imaging KW - density weighting KW - parallel imaging KW - VIDE KW - VIDED KW - Optimierung KW - NMR-Bildgebung KW - NMR-Mammographie KW - Koronarperfusion Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-71834 ER - TY - JOUR A1 - Guggenberger, Konstanze Viktoria A1 - Bley, Thorsten Alexander T1 - Imaging in Vasculitis JF - Current Rheumatology Reports N2 - Purpose of Review: Vasculitides are characterized by mostly autoimmunologically induced inflammatory processes of vascularstructures. They have various clinical and radiologic appearances. Early diagnosis and reliable monitoring are indispensable foradequate therapy to prevent potentially serious complications. Imaging, in addition to laboratory tests and physical examination,constitutes a key component in assessing disease extent and activity. This review presents current standards and some typicalfindings in the context of imaging in vasculitis with particular attention to large vessel vasculitides. Recent Findings: Recently, imaging has gained importance in the management of vasculitis, especially regarding large vesselvasculitides (LVV). Recently, EULAR (European League Against Rheumatism) has launched its recommendations concerningthe diagnosis of LVVs. Imaging is recommended as the preferred complement to clinical examination. Color-coded duplexsonography is considered the first choice imaging test in suspected giant cell arteritis, and magnetic resonance imaging isconsidered the first choice in suspected Takayasu’sarteritis. Summary: Due to diversity of clinical and radiologic presentations, diagnosis and therapy monitoring of vasculitides mayconstitute a challenge. As a result of ongoing technological progress, a variety of non-invasive imaging modalities now playan elemental role in the interdisciplinary management of vasculitic diseases. KW - Vasculitis KW - Large vessel vasculitides (LVV) KW - Giant cell arteritis (GCA KW - Imaging KW - Magnetic resonance imaging(MRI) KW - EULAR guidelines Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-232762 SN - 1523-3774 VL - 22 IS - 34 ER - TY - JOUR A1 - Guggenberger, Konstanze V. A1 - Vogt, Marius L. A1 - Song, Jae W. A1 - Weng, Andreas M. A1 - Fröhlich, Matthias A1 - Schmalzing, Marc A1 - Venhoff, Nils A1 - Hillenkamp, Jost A1 - Pham, Mirko A1 - Meckel, Stephan A1 - Bley, Thorsten A. T1 - Intraorbital findings in giant cell arteritis on black blood MRI JF - European Radiology N2 - Objective Blindness is a feared complication of giant cell arteritis (GCA). However, the spectrum of pathologic orbital imaging findings on magnetic resonance imaging (MRI) in GCA is not well understood. In this study, we assess inflammatory changes of intraorbital structures on black blood MRI (BB-MRI) in patients with GCA compared to age-matched controls. Methods In this multicenter case-control study, 106 subjects underwent BB-MRI. Fifty-six patients with clinically or histologically diagnosed GCA and 50 age-matched controls without clinical or laboratory evidence of vasculitis were included. All individuals were imaged on a 3-T MR scanner with a post-contrast compressed-sensing (CS) T1-weighted sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) BB-MRI sequence. Imaging results were correlated with available clinical symptoms. Results Eighteen of 56 GCA patients (32%) showed inflammatory changes of at least one of the intraorbital structures. The most common finding was enhancement of at least one of the optic nerve sheaths (N = 13, 72%). Vessel wall enhancement of the ophthalmic artery was unilateral in 8 and bilateral in 3 patients. Enhancement of the optic nerve was observed in one patient. There was no significant correlation between imaging features of inflammation and clinically reported orbital symptoms (p = 0.10). None of the age-matched control patients showed any inflammatory changes of intraorbital structures. Conclusions BB-MRI revealed inflammatory findings in the orbits in up to 32% of patients with GCA. Optic nerve sheath enhancement was the most common intraorbital inflammatory change on BB-MRI. MRI findings were independent of clinically reported orbital symptoms. Key Points • Up to 32% of GCA patients shows signs of inflammation of intraorbital structures on BB-MRI. • Enhancement of the optic nerve sheath is the most common intraorbital finding in GCA patients on BB-MRI. • Features of inflammation of intraorbital structures are independent of clinically reported symptoms. KW - giant cell arteritis KW - magnetic resonance imaging KW - orbit KW - ophthalmic artery KW - optic nerve Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324978 VL - 33 IS - 4 ER - TY - THES A1 - Gubik, Sebastian T1 - Quantifizierung der Myokardperfusion mittels Dual Saturation Time Perfusion Imaging T1 - Quantification of Myocardial Perfusion using Dual Saturation Time Perfusion Imaging N2 - The Dual-Echo-Sequence to quantify myocardial perfusion was presented as an alternative to the prebolus-technique. The Arterial Input Function was determined using two different methods (‚KonFactor’- and ‚IndivFactor’-Method) in order to compare the calculated myocardial perfusion values with those of the prebolus-technique. In this study, there was no concordance between the data from the prebolus-technique and the other two techniques, called ,KonFactor’- and ‚IndivFactor’-method. Consequently, the Dual-Echo-Sequence has to be investigated in further studies, especially the image aquisition problems have to be looked into thoroughly. N2 - In dieser Arbeit wurde die Dual-Echo-Sequenz zur Quantifizierung der Myokardperfusion als Alternative zur Präbolus-Technik vorgestellt. Es wurde die Arterial Input Function auf zwei verschiedene Weisen (KonFaktor- und IndivFaktor- Methode) ermittelt und die daraus errechneten myokardialen Perfusionswerte mit denen der Präbolus-Technik verglichen. In dieser Studie konnte keine eindeutige Übereinstimmung der Werte aus der Präbolus- Technik mit den Werten aus der KonFaktor- beziehungsweise IndivFaktor-Methode nachgewiesen werden. Folglich gilt es die Möglichkeiten der Dual-Echo-Sequenz weiterhin zu untersuchen. Für weitere Studien sollten vor allem die technischen Mängel bei der Bildakquisition analysiert werden. KW - Myokardperfusion KW - Quantifizierung Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-178304 ER - TY - JOUR A1 - Gruschwitz, Philipp A1 - Hartung, Viktor A1 - Kleefeldt, Florian A1 - Peter, Dominik A1 - Lichthardt, Sven A1 - Huflage, Henner A1 - Grunz, Jan-Peter A1 - Augustin, Anne Marie A1 - Ergün, Süleyman A1 - Bley, Thorsten Alexander A1 - Petritsch, Bernhard T1 - Continuous extracorporeal femoral perfusion model for intravascular ultrasound, computed tomography and digital subtraction angiography JF - PLoS One N2 - Objectives We developed a novel human cadaveric perfusion model with continuous extracorporeal femoral perfusion suitable for performing intra-individual comparison studies, training of interventional procedures and preclinical testing of endovascular devices. Objective of this study was to introduce the techniques and evaluate the feasibility for realistic computed tomography angiography (CTA), digital subtraction angiography (DSA) including vascular interventions, and intravascular ultrasound (IVUS). Methods The establishment of the extracorporeal perfusion was attempted using one formalin-fixed and five fresh-frozen human cadavers. In all specimens, the common femoral and popliteal arteries were prepared, introducer sheaths inserted, and perfusion established by a peristaltic pump. Subsequently, we performed CTA and bilateral DSA in five cadavers and IVUS on both legs of four donors. Examination time without unintentional interruption was measured both with and without non-contrast planning CT. Percutaneous transluminal angioplasty and stenting was performed by two interventional radiologists on nine extremities (five donors) using a broad spectrum of different intravascular devices. Results The perfusion of the upper leg arteries was successfully established in all fresh-frozen but not in the formalin-fixed cadaver. The experimental setup generated a stable circulation in each procedure (ten upper legs) for a period of more than six hours. Images acquired with CT, DSA and IVUS offered a realistic impression and enabled the sufficient visualization of all examined vessel segments. Arterial cannulating, percutaneous transluminal angioplasty as well as stent deployment were feasible in a way that is comparable to a vascular intervention in vivo. The perfusion model allowed for introduction and testing of previously not used devices. Conclusions The continuous femoral perfusion model can be established with moderate effort, works stable, and is utilizable for medical imaging of the peripheral arterial system using CTA, DSA and IVUS. Therefore, it appears suitable for research studies, developing skills in interventional procedures and testing of new or unfamiliar vascular devices. KW - continuous extracorporeal femoral perfusion model KW - novel human cadaveric perfusion model KW - computed tomography angiography (CTA) KW - digital subtraction angiography (DSA) KW - intravascular ultrasound (IVUS) Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-350136 SN - 1932-6203 VL - 18 IS - 5 ER - TY - JOUR A1 - Gruschwitz, Philipp A1 - Hartung, Viktor A1 - Kleefeldt, Florian A1 - Ergün, Süleyman A1 - Lichthardt, Sven A1 - Huflage, Henner A1 - Hendel, Robin A1 - Kunz, Andreas Steven A1 - Pannenbecker, Pauline A1 - Kuhl, Philipp Josef A1 - Augustin, Anne Marie A1 - Bley, Thorsten Alexander A1 - Petritsch, Bernhard A1 - Grunz, Jan-Peter T1 - Standardized assessment of vascular reconstruction kernels in photon-counting CT angiographies of the leg using a continuous extracorporeal perfusion model JF - Scientific Reports N2 - This study evaluated the influence of different vascular reconstruction kernels on the image quality of CT angiographies of the lower extremity runoff using a 1st-generation photon-counting-detector CT (PCD-CT) compared with dose-matched examinations on a 3rd-generation energy-integrating-detector CT (EID-CT). Inducing continuous extracorporeal perfusion in a human cadaveric model, we performed CT angiographies of eight upper leg arterial runoffs with radiation dose-equivalent 120 kVp acquisition protocols (CTDIvol 5 mGy). Reconstructions were executed with different vascular kernels, matching the individual modulation transfer functions between scanners. Signal-to-noise-ratios (SNR) and contrast-to-noise-ratios (CNR) were computed to assess objective image quality. Six radiologists evaluated image quality subjectively using a forced-choice pairwise comparison tool. Interrater agreement was determined by calculating Kendall’s concordance coefficient (W). The intraluminal attenuation of PCD-CT images was significantly higher than of EID-CT (414.7 ± 27.3 HU vs. 329.3 ± 24.5 HU; p < 0.001). Using comparable kernels, image noise with PCD-CT was significantly lower than with EID-CT (p ≤ 0.044). Correspondingly, SNR and CNR were approximately twofold higher for PCD-CT (p < 0.001). Increasing the spatial frequency for PCD-CT reconstructions by one level resulted in similar metrics compared to EID-CT (CNRfat; EID-CT Bv49: 21.7 ± 3.7 versus PCD-CT Bv60: 21.4 ± 3.5). Overall image quality of PCD-CTA achieved ratings superior to EID-CTA irrespective of the used reconstruction kernels (best: PCD-CT Bv60; worst: EID-CT Bv40; p < 0.001). Interrater agreement was good (W = 0.78). Concluding, PCD-CT offers superior intraluminal attenuation, SNR, and CNR compared to EID-CT in angiographies of the upper leg arterial runoff. Combined with improved subjective image quality, PCD-CT facilitates the use of sharper convolution kernels and ultimately bears the potential of improved vascular structure assessability. KW - experimental models of disease KW - preclinical research KW - translational research Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357912 VL - 13 ER - TY - JOUR A1 - Gruschwitz, Philipp A1 - Hartung, Viktor A1 - Ergün, Süleyman A1 - Peter, Dominik A1 - Lichthardt, Sven A1 - Huflage, Henner A1 - Hendel, Robin A1 - Pannenbecker, Pauline A1 - Augustin, Anne Marie A1 - Kunz, Andreas Steven A1 - Feldle, Philipp A1 - Bley, Thorsten Alexander A1 - Grunz, Jan-Peter T1 - Comparison of ultrahigh and standard resolution photon-counting CT angiography of the femoral arteries in a continuously perfused in vitro model JF - European Radiology Experimental N2 - Background With the emergence of photon-counting CT, ultrahigh-resolution (UHR) imaging can be performed without dose penalty. This study aims to directly compare the image quality of UHR and standard resolution (SR) scan mode in femoral artery angiographies. Methods After establishing continuous extracorporeal perfusion in four fresh-frozen cadaveric specimens, photon-counting CT angiographies were performed with a radiation dose of 5 mGy and tube voltage of 120 kV in both SR and UHR mode. Images were reconstructed with dedicated convolution kernels (soft: Body-vascular (Bv)48; sharp: Bv60; ultrasharp: Bv76). Six radiologists evaluated the image quality by means of a pairwise forced-choice comparison tool. Kendall’s concordance coefficient (W) was calculated to quantify interrater agreement. Image quality was further assessed by measuring intraluminal attenuation and image noise as well as by calculating signal-to-noise ratio (SNR) and contrast-to-noise ratios (CNR). Results UHR yielded lower noise than SR for identical reconstructions with kernels ≥ Bv60 (p < 0.001). UHR scans exhibited lower intraluminal attenuation compared to SR (Bv60: 406.4 ± 25.1 versus 418.1 ± 30.1 HU; p < 0.001). Irrespective of scan mode, SNR and CNR decreased while noise increased with sharper kernels but UHR scans were objectively superior to SR nonetheless (Bv60: SNR 25.9 ± 6.4 versus 20.9 ± 5.3; CNR 22.7 ± 5.8 versus 18.4 ± 4.8; p < 0.001). Notably, UHR scans were preferred in subjective assessment when images were reconstructed with the ultrasharp Bv76 kernel, whereas SR was rated superior for Bv60. Interrater agreement was high (W = 0.935). Conclusions Combinations of UHR scan mode and ultrasharp convolution kernel are able to exploit the full image quality potential in photon-counting CT angiography of the femoral arteries. Relevance statement The UHR scan mode offers improved image quality and may increase diagnostic accuracy in CT angiography of the peripheral arterial runoff when optimized reconstruction parameters are chosen. Key points • UHR photon-counting CT improves image quality in combination with ultrasharp convolution kernels. • UHR datasets display lower image noise compared with identically reconstructed standard resolution scans. • Scans in UHR mode show decreased intraluminal attenuation compared with standard resolution imaging. KW - CT angiography KW - femoral arteries KW - photon-counting computed tomography (CT) KW - small pixel effect KW - ultrahigh resolution Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357905 VL - 7 ER - TY - JOUR A1 - Grunz, Jan-Peter A1 - Wenig, Andreas Max A1 - Kunz, Andreas Steven A1 - Veyhl-Wichmann, Maike A1 - Schmitt, Rainer A1 - Gietzen, Carsten Herbert A1 - Pennig, Lenhard A1 - Herz, Stefan A1 - Ergün, Süleyman A1 - Bley, Thorsten Alexander A1 - Gassenmaier, Tobias T1 - 3D cone-beam CT with a twin robotic x-ray system in elbow imaging: comparison of image quality to high-resolution multidetector CT JF - European Radiology Experimental N2 - Background Elbow imaging is challenging with conventional multidetector computed tomography (MDCT), while cone-beam CT (CBCT) provides superior options. We compared intra-individually CBCT versus MDCT image quality in cadaveric elbows. Methods A twin robotic x-ray system with new CBCT mode and a high-resolution clinical MDCT were compared in 16 cadaveric elbows. Both systems were operated with a dedicated low-dose (LD) protocol (equivalent volume CT dose index [CTDI\(_{vol(16 cm)}\)] = 3.3 mGy) and a regular clinical scan dose (RD) protocol (CTDI\(_{vol(16 cm)}\) = 13.8 mGy). Image quality was evaluated by two radiologists (R1 and R2) on a seven-point Likert scale, and estimation of signal intensity in cancellous bone was conducted. Wilcoxon signed-rank tests and intraclass correlation coefficient (ICC) statistics were used. Results The CBCT prototype provided superior subjective image quality compared to MDCT scans (for RD, p ≤ 0.004; for LD, p ≤ 0.001). Image quality was rated very good or excellent in 100% of the cases by both readers for RD CBCT, 100% (R1) and 93.8% (R2) for LD CBCT, 62.6% and 43.8% for RD MDCT, and 0.0% and 0.0% for LD MDCT. Single-measure ICC was 0.95 (95% confidence interval 0.91–0.97; p < 0.001). Software-based assessment supported subjective findings with less “undecided” pixels in CBCT than dose-equivalent MDCT (p < 0.001). No significant difference was found between LD CBCT and RD MDCT. Conclusions In cadaveric elbow studies, the tested cone-beam CT prototype delivered superior image quality compared to high-end multidetector CT and showed a potential for considerable dose reduction. KW - Cancellous bone KW - Cone-beam computed tomography KW - Elbow KW - Elbow joint KW - Multidetector computed tomography Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229877 VL - 4 ER - TY - JOUR A1 - Grunz, Jan-Peter A1 - Sailer, Lukas A1 - Lang, Patricia A1 - Schüle, Simone A1 - Kunz, Andreas Steven A1 - Beer, Meinrad A1 - Hackenbroch, Carsten T1 - Dual-energy CT in sacral fragility fractures: defining a cut-off Hounsfield unit value for the presence of traumatic bone marrow edema in patients with osteoporosis JF - BMC Musculoskeletal Disorders N2 - Background Demographic change entails an increasing incidence of fragility fractures. Dual-energy CT (DECT) with virtual non-calcium (VNCa) reconstructions has been introduced as a promising diagnostic method for evaluating bone microarchitecture and marrow simultaneously. This study aims to define the most accurate cut-off value in Hounsfield units (HU) for discriminating the presence and absence of bone marrow edema (BME) in sacral fragility fractures. Methods Forty-six patients (40 women, 6 men; 79.7 ± 9.2 years) with suspected fragility fractures of the sacrum underwent both DECT (90 kVp / 150 kVp with tin prefiltration) and MRI. Nine regions-of-interest were placed in each sacrum on DECT-VNCa images. The resulting 414 HU measurements were stratified into “edema” (n = 80) and “no edema” groups (n = 334) based on reference BME detection in T2-weighted MRI sequences. Area under the receiver operating characteristic curve was calculated to determine the desired cut-off value and an associated conspicuity range for edema detection. Results The mean density within the “edema” group of measurements (+ 3.1 ± 8.3 HU) was substantially higher compared to the “no edema” group (-51.7 ± 21.8 HU; p < 0.010). Analysis in DECT-VNCa images suggested a cut-off value of -12.9 HU that enabled sensitivity and specificity of 100% for BME detection compared to MRI. A range of HU values between -14.0 and + 20.0 is considered indicative of BME in the sacrum. Conclusions Quantitative analysis of DECT-VNCa with a cut-off of -12.9 HU allows for excellent diagnostic accuracy in the assessment of sacral fragility fractures with associated BME. A diagnostic “one-stop-shop” approach without additional MRI is feasible. KW - virtual noncalcium imaging KW - dual-energy computed tomography KW - fragility fracture KW - bone bruise KW - bone marrow edema Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301125 VL - 23 IS - 1 ER - TY - JOUR A1 - Grunz, Jan-Peter A1 - Pennig, Lenhard A1 - Fieber, Tabea A1 - Gietzen, Carsten Herbert A1 - Heidenreich, Julius Frederik A1 - Huflage, Henner A1 - Gruschwitz, Philipp A1 - Kuhl, Philipp Josef A1 - Petritsch, Bernhard A1 - Kosmala, Aleksander A1 - Bley, Thorsten Alexander A1 - Gassenmaier, Tobias T1 - Twin robotic x-ray system in small bone and joint trauma: Impact of cone-beam computed tomography on treatment decisions JF - European Radiology N2 - Objectives Trauma evaluation of extremities can be challenging in conventional radiography. A multi-use x-ray system with cone-beam CT (CBCT) option facilitates ancillary 3-D imaging without repositioning. We assessed the clinical value of CBCT scans by analyzing the influence of additional findings on therapy. Methods Ninety-two patients underwent radiography and subsequent CBCT imaging with the twin robotic scanner (76 wrist/hand/finger and 16 ankle/foot/toe trauma scans). Reports by on-call radiologists before and after CBCT were compared regarding fracture detection, joint affliction, comminuted injuries, and diagnostic confidence. An orthopedic surgeon recommended therapy based on reported findings. Surgical reports (N = 52) and clinical follow-up (N = 85) were used as reference standard. Results CBCT detected more fractures (83/64 of 85), joint involvements (69/53 of 71), and multi-fragment situations (68/50 of 70) than radiography (all p < 0.001). Six fractures suspected in radiographs were ruled out by CBCT. Treatment changes based on additional information from CBCT were recommended in 29 patients (31.5%). While agreement between advised therapy before CBCT and actual treatment was moderate (κ = 0.41 [95% confidence interval 0.35–0.47]; p < 0.001), agreement after CBCT was almost perfect (κ = 0.88 [0.83–0.93]; p < 0.001). Diagnostic confidence increased considerably for CBCT studies (p < 0.001). Median effective dose for CBCT was 4.3 μSv [3.3–5.3 μSv] compared to 0.2 μSv [0.1–0.2 μSv] for radiography. Conclusions CBCT provides advantages for the evaluation of acute small bone and joint trauma by detecting and excluding extremity fractures and fracture-related findings more reliably than radiographs. Additional findings induced therapy change in one third of patients, suggesting substantial clinical impact. KW - cone-beamcomputed tomography KW - extremities KW - fractures, bone KW - radiography Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235233 SN - 0938-7994 VL - 31 ER - TY - JOUR A1 - Grunz, Jan-Peter A1 - Kunz, Andreas Steven A1 - Baumann, Freerk T. A1 - Hasenclever, Dirk A1 - Sieren, Malte Maria A1 - Heldmann, Stefan A1 - Bley, Thorsten Alexander A1 - Einsele, Hermann A1 - Knop, Stefan A1 - Jundt, Franziska T1 - Assessing osteolytic lesion size on sequential CT scans is a reliable study endpoint for bone remineralization in newly diagnosed multiple myeloma JF - Cancers N2 - Multiple myeloma (MM) frequently induces persisting osteolytic manifestations despite hematologic treatment response. This study aimed to establish a biometrically valid study endpoint for bone remineralization through quantitative and qualitative analyses in sequential CT scans. Twenty patients (seven women, 58 ± 8 years) with newly diagnosed MM received standardized induction therapy comprising the anti-SLAMF7 antibody elotuzumab, carfilzomib, lenalidomide, and dexamethasone (E-KRd). All patients underwent whole-body low-dose CT scans before and after six cycles of E-KRd. Two radiologists independently recorded osteolytic lesion sizes, as well as the presence of cortical destruction, pathologic fractures, rim and trabecular sclerosis. Bland–Altman analyses and Krippendorff’s α were employed to assess inter-reader reliability, which was high for lesion size measurement (standard error 1.2 mm) and all qualitative criteria assessed (α ≥ 0.74). After six cycles of E-KRd induction, osteolytic lesion size decreased by 22% (p < 0.001). While lesion size response did not correlate with the initial lesion size at baseline imaging (Pearson’s r = 0.144), logistic regression analysis revealed that the majority of responding osteolyses exhibited trabecular sclerosis (p < 0.001). The sum of osteolytic lesion sizes on sequential CT scans defines a reliable study endpoint to characterize bone remineralization. Patient level response is strongly associated with the presence of trabecular sclerosis. KW - multiple myeloma KW - bone remineralization KW - computed tomography KW - whole-body imaging Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-362526 SN - 2072-6694 VL - 15 IS - 15 ER - TY - JOUR A1 - Grunz, Jan-Peter A1 - Gietzen, Carsten Herbert A1 - Luetkens, Karsten A1 - Wagner, Matthias A1 - Kalb, Karlheinz A1 - Bley, Thorsten Alexander A1 - Lehmkul, Luka A1 - van Schoonhoven, Jörg A1 - Gassenmaier, Tobias A1 - Schmitt, Rainer T1 - The importance of radial multiplanar reconstructions for assessment of triangular fibrocartilage complex injury in CT arthrography of the wrist JF - BMC Musculoskeletal Disorders N2 - Background: Triangular fibrocartilage complex (TFCC) lesions commonly cause ulnar-sided wrist pain and instability of the distal radioulnar joint. Due to its triangular shape, discontinuity of the TFCC is oftentimes difficult to visualize in radiological standard planes. Radial multiplanar reconstructions (MPR) may have the potential to simplify diagnosis in CT wrist arthrography. The objective of this study was to assess diagnostic advantages provided by radial MPR over standard planes for TFCC lesions in CT arthrography. Methods: One hundred six patients (49 women, 57 men; mean age 44.2 ± 15.8 years) underwent CT imaging after wrist arthrography. Two radiologists (R1, R2) retrospectively analyzed three randomized datasets for each CT arthrography. One set contained axial, coronal and sagittal planes (MPR\(_{Standard}\)), while the other two included an additional radial reconstruction with the rotating center either atop the ulnar styloid (MPR\(_{Styloid}\)) or in the ulnar fovea (MPR\(_{Fovea}\)). Readers evaluated TFCC differentiability and condition. Suspected lesions were categorized using Palmer’s and Atzei’s classification and diagnostic confidence was stated on a fivepoint Likert scale. Results: Compared to standard planes, differentiability of the superficial and deep TFCC layer was superior in radial reconstructions (R1/R2; MPR\(_{Fovea}\): p < 0.001; MPRStyloid: p ≤ 0.007). Palmer and Atzei lesions were present in 86.8% (92/106) and 52.8% (56/106) of patients, respectively. Specificity, sensitivity and accuracy for central Palmer lesions did not differ in radial and standard MPR. For peripheral Atzei lesions, sensitivity (MPR\(_{Standard}\) 78.6%/80.4%, MPR\(_{Styloid}\) 94.6%/94.6%, MPR\(_{Fovea}\) 91.1%/89.3%) and accuracy (MPR\(_{Standard}\) 86.8%/86.8%, MPR\(_{Styloid}\) 96.2%/96.2%, MPR\(_{Fovea}\) 94.3%/93.4%) improved with additional styloid-centered (p = 0.004/0.008) and foveacentered (p = 0.039/0.125) reconstructions. No substantial difference was observed between both radial MPR (p = 0.688/0.250). Interrater agreement was almost perfect for each dataset (κ\(_{Standard}\) = 0.876, κ\(_{Styloid}\) = 0.894, κ\(_{Fovea}\) = 0.949). Diagnostic confidence increased with addition of either radial MPR (p < 0.001). Conclusions: Ancillary radial planes improve accuracy and diagnostic confidence for detection of peripheral TFCC lesions in CT arthrography of the wrist. KW - Triangular fibrocartilage KW - Wrist KW - Arthrography KW - Tomography KW - X-ray computed Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236075 VL - 21 ER - TY - JOUR A1 - Grebe, Sören Jendrik A1 - Malzahn, Uwe A1 - Donhauser, Julian A1 - Liu, Dan A1 - Wanner, Christoph A1 - Krane, Vera A1 - Hammer, Fabian T1 - Quantification of left ventricular mass by echocardiography compared to cardiac magnet resonance imaging in hemodialysis patients JF - Cardiovascular Ultrasound N2 - Background: Left ventricular hypertrophy (LVH), defined by the left ventricular mass index (LVMI), is highly prevalent in hemodialysis patients and a strong independent predictor of cardiovascular events. Compared to cardiac magnetic resonance imaging (CMR), echocardiography tends to overestimate the LVMI. Here, we evaluate the diagnostic performance of transthoracic echocardiography (TTE) compared to CMR regarding the assessment of LVMI in hemodialysis patients. Methods: TTR and CMR data for 95 hemodialysis patients who participated in the MiREnDa trial were analyzed. The LVMI was calculated by two-dimensional (2D) TTE-guided M-mode measurements employing the American Society of Echocardiography (ASE) and Teichholz (Th) formulas, which were compared to the reference method, CMR. Results: LVH was present in 44% of patients based on LVMI measured by CMR. LVMI measured by echocardiography correlated moderately with CMR, ASE: r = 0.44 (0.34-0.62); Th: r = 0.44 (0.32-0.62). Compared to CMR, both echocardiographic formulas overestimated LVMI (mean increment LVMI (ASE-CMR): 19.5 +/- 19.48 g/m(2),p < 0.001; mean increment LVMI (Th-CMR): 15.9 +/- 15.89 g/m(2),p < 0.001). We found greater LVMI overestimation in patients with LVH using the ASE formula compared to the Th formula. Stratification of patients into CMR LVMI quartiles showed a continuous decrease in increment LVMI with increasing CMR LVMI quartiles for the Th formula (p < 0.001) but not for the ASE formula (p = 0.772). Bland-Altman analysis showed that the Th formula had a constant bias independent of LVMI. Both methods had good discrimination ability for the detection of LVH (ROC-AUC: 0.819 (0.737-0.901) and 0.808 (0.723-0.892) for Th and ASE, respectively). Conclusions: The ASE and Th formulas overestimate LVMI in hemodialysis patients. However, the overestimation is less with the Th formula, particularly with increasing LVMI. The results suggest that the Th formula should be preferred for measurement of LVMI in chronic hemodialysis patients. KW - Teichholz formula KW - ASE formula KW - echocardiography KW - left ventricular hypertrophy KW - left ventricular mass index KW - hemodialysis Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-229282 VL - 18 ER - TY - THES A1 - Grathwohl, Daniela T1 - Quantitative Sonoelastographie der Leber bei Kindern und Jugedlichen mit Cystischer Fibrose T1 - Quantitative ultrasound imaging of the liver in children and adolescents with cystic fibrosis N2 - Morbidität und Mortalität der Lebererkrankung im Rahmen der Cystischen Fiborse (Cystic fibrosis liver disease, CFLD) sind vornehmlich von Ausmaß und Progredienz der Leberfibrose abhängig. Aufgrund der fehlenden Genauigkeit der bisherigen diagnostischen Verfahren werden viele der an CF erkrankten Menschen erst in fortgeschrittenen Stadien diagnostiziert. Schwere Komplikationen einer Leberzirrhose treten häufig bereits im Kindesalter auf. Die Quantitative Sonoelastographie, hier die Acoustic Radiation Force Impulse (ARFI)-Elastographie, ist ein vielversprechendes, nicht-invasives und strahlenfreies Verfahren zur Messung der Gewebesteifigkeit. Anhand dieser retrospektiven, monozentrischen Studie soll die ARFI-Elastographie im Hinblick auf den klinischen Einsatz bei der CFLD-Diagnostik untersucht werden. Es wurde eruiert, ob sich mittels ARFI-Elastographie Rückschlüsse auf eine CFLD und deren Schweregrade ziehen lassen. Hierfür wurden die ARFI-Messungen verschiedener Lebersegmente von 62 an CF erkrankten und 19 lebergesunden Kindern und Jugendlichen verglichen. Zudem erfolgte die Korrelation der Ergebnisse mit zwei etablierten klinischen Leberfibrose-Scores (APRI, Williams-Score). Im Patientenkollektiv konnten tendenziell erhöhte Scherwellengeschwindigkeiten, entsprechend einer fibrotischen Aktivität, gemessen werden. Die transkostale Messposition in Segment VII/VIII (TC VII/VIII) erwies sich als zuverlässigste Position zur Differenzierung zwischen einer CF-Hepatopathie und einem gesunden Leberparenchym. Hingegen war das Errechnen von Cut-off Werten zur Graduierung von Fibrosestadien nicht möglich. Auch war keine Korrelation zu Leberfiborsescores feststellbar. Insgesamt zeigt sich, dass die Diagnosestellung einer CFLD aktuell nur in Kombination mit bisherigen Messmethoden wie der klinischen Untersuchung, der Laboranalytik und der Sonographie möglich ist. Die Interpretation der ARFI-cut-off Werte bleibt aufgrund mangelnder Sensitivität und Spezifität und vor dem Hintergrund der CF-typischen heterogenen Leberpathologie erschwert. Die ARFI-Elastographie kann als zusätzlicher Baustein in der Diagnostik der CFLD, bei unklaren Befundkonstellationen oder zum Therapie-Monitoring herangezogen werden. Um einen klaren klinischen Einsatz in der Routinediagnostik zu definieren bedarf es weiterer großer, multizentrischer und prospektiver Studien. N2 - The liver-associated morbidity and mortality of the patients with cystic fibrosis (CF) depends on the progression of liver fibrosis. The lack of sensitive diagnostics in the early stages of fibrosis is a key reason for delayed diagnosis, often when complications from liver cirrhosis have already developed in childhood. Quantitative ultrasound (US) imaging, such as Acoustic Radiation Force Imaging (ARFI)-Elastography, is a modern and non-invasive technique for the measurement of tissue stiffness. ARFI-Elastography could improve the detection of Liver Disease (LD) in CF over today‘s routine diagnostics. The aim of this single centre, retrospective study was to analyse the diagnostic performance and the clinical use of the ARFI-method with regard to the early detection of parenchymal changes in Cystic Fibrosis Liver Disease (CFLD). ARFI-data of 62 patients with CF were compared to 19 healthy controls. Results have been related to common and previously established scores (APRI, Williams-Score) for fibrosis in CF. ARFI measurements were higher in the patient group. In particular, the transcostal imaging of segments VII/VIII (TC CII/VIII) of the right liver lobe showed a statistically significant difference between patients with CF and healthy controls. However, because of the wide range of the measurements it was not possible to establish cutoff-values to differentiate stages of liver stiffness and there was no correlation to clinical scores of fibrosis. Due to the lack of sensitivity and specificity of the ARFI cutoff-value and the knowledge of the heterogeneous pathology of cirrhosis in CF, interpretation of ARFI measurements remains challenging. On the basis of our findings, we conclude that ARFI may have a useful role in combination with routine assessments including physical examination, screening laboratory values and US-imaging, to detect, diagnose and monitor CFLD. Larger prospective validation studies are required to establish how ARFI can best be incorporated into routine clinical practice. KW - Ultraschall-Elastographie KW - Cystische Fibrose KW - Quantitative Sonoelastographie KW - Acoustic radiation force imaging (ARFI) KW - Leberfibrose KW - Cystic fibrosis liver disease (CFLD) Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250621 ER - TY - JOUR A1 - Gilbert, Fabian A1 - Klein, Detlef A1 - Weng, Andreas Max A1 - Köstler, Herbert A1 - Schmitz, Benedikt A1 - Schmalzl, Jonas A1 - Böhm, Dirk T1 - Supraspinatus muscle elasticity measured with real time shear wave ultrasound elastography correlates with MRI spectroscopic measured amount of fatty degeneration JF - BMC Muscoskeletal Disorders N2 - Background: Fatty Degeneration (FD) of the rotator cuff muscles influences functional and anatomical outcome after rotator cuff repair. The MRI based estimation of fatty degeneration is the gold standard. There is some evidence that Ultrasound elastography (EUS) can detect local differences of tissue stiffness in muscles and tendons. Shear-wave elastography (SWE) was evaluated to determine the extent to which shear wave velocity was associated with measures of fatty degeneration. MRI-spectroscopic fat measurement was used as a reference to quantify the amount of fat in the muscle belly. Methods: Forty-two patients underwent SWE of the supraspinatus muscles at its thickest diameter. After ultrasound evaluation an MRI-spectroscopic fat measurement of the supraspinatus muscle was performed using the SPLASH-technique. A gel filled capsule was used to locate the measured area in the MRI. The values of shear wave velocity (SWV) measured with SWE and spectroscopic fat measurement were correlated statistically using Pearson’s correlation test. Results: Correlation of the fat amount measured with MRI-spectroscopy and the SWV measured with SWE was ρ =0.82. Spectroscopic measured fat ratio of the supraspinatus muscle ranged from 0% to 77.41% and SWV from 1.59 m/s to 5.32 m/s. In 4 patients no sufficient SWE could be performed, these individuals showed a larger diameter of the overlying soft tissue. SWV measured with SWE showed a good correlation with MRI spectroscopic fat amount of the supraspinatus muscle. Conclusion: These preliminary data suggest that SWE may be a sufficient tool in detecting and estimating the amount of fatty degeneration in the supraspinatus muscle in real time. Large overlying soft tissue may be a limitation in performing sufficient EUS. KW - shoulder surgery KW - rotator cuff KW - MRI KW - ultrasound KW - fatty degeneration Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-159378 VL - 18 IS - 549 ER - TY - JOUR A1 - Gilbert, Fabian A1 - Böhm, Dirk A1 - Eden, Lars A1 - Schmalzl, Jonas A1 - Meffert, Rainer H. A1 - Köstler, Herbert A1 - Weng, Andreas M. A1 - Ziegler, Dirk T1 - Comparing the MRI-based Goutallier Classification to an experimental quantitative MR spectroscopic fat measurement of the supraspinatus muscle JF - BMC Musculoskeletal Disorders N2 - Background The Goutallier Classification is a semi quantitative classification system to determine the amount of fatty degeneration in rotator cuff muscles. Although initially proposed for axial computer tomography scans it is currently applied to magnet-resonance-imaging-scans. The role for its clinical use is controversial, as the reliability of the classification has been shown to be inconsistent. The purpose of this study was to compare the semi quantitative MRI-based Goutallier Classification applied by 5 different raters to experimental MR spectroscopic quantitative fat measurement in order to determine the correlation between this classification system and the true extent of fatty degeneration shown by spectroscopy. Methods MRI-scans of 42 patients with rotator cuff tears were examined by 5 shoulder surgeons and were graduated according to the MRI-based Goutallier Classification proposed by Fuchs et al. Additionally the fat/water ratio was measured with MR spectroscopy using the experimental SPLASH technique. The semi quantitative grading according to the Goutallier Classification was statistically correlated with the quantitative measured fat/water ratio using Spearman’s rank correlation. Results Statistical analysis of the data revealed only fair correlation of the Goutallier Classification system and the quantitative fat/water ratio with R = 0.35 (p < 0.05). By dichotomizing the scale the correlation was 0.72. The interobserver and intraobserver reliabilities were substantial with R = 0.62 and R = 0.74 (p < 0.01). Conclusion The correlation between the semi quantitative MRI based Goutallier Classification system and MR spectroscopic fat measurement is weak. As an adequate estimation of fatty degeneration based on standard MRI may not be possible, quantitative methods need to be considered in order to increase diagnostic safety and thus provide patients with ideal care in regard to the amount of fatty degeneration. Spectroscopic MR measurement may increase the accuracy of the Goutallier classification and thus improve the prediction of clinical results after rotator cuff repair. However, these techniques are currently only available in an experimental setting. KW - rotator cuff KW - MRI KW - spectroscopy KW - goutallier KW - classification KW - shoulder surgery Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147788 VL - 17 IS - 355 ER - TY - JOUR A1 - Gilbert, F. A1 - Schneemann, C. A1 - Scholz, C. J. A1 - Kickuth, R. A1 - Meffert, R. H. A1 - Wildenauer, R. A1 - Lorenz, U. A1 - Kellersmann, R. A1 - Busch, A. T1 - Clinical implications of fracture-associated vascular damage in extremity and pelvic trauma JF - BMC Muscuskeletal Disorders N2 - Background: Vascular damage in polytrauma patients is associated with high mortality and morbidity. Therefore, specific clinical implications of vascular damage with fractures in major trauma patients are reassessed. Methods: This comprehensive nine-year retrospective single center cohort study analyzed demography, laboratory, treatment and outcome data from 3689 patients, 64 patients with fracture-associated vascular injuries were identified and were compared to a control group. Results: Vascular damage occurred in 7% of patients with upper and lower limb and pelvic fractures admitted to the trauma room. Overall survival was 80% in pelvic fracture and 97% in extremity fracture patients and comparable to non-vascular trauma patients. Additional arterial damage required substantial fluid administration and was visible as significantly anemia and disturbed coagulation tests upon admission. Open procedures were done in over 80% of peripheral extremity vascular damage. Endovascular procedures were predominant (87%) in pelvic injury. Conclusion: Vascular damage is associated with high mortality rates especially in combination with pelvic fractures. Initial anemia, disturbed coagulation tests and the need for extensive pre-clinical fluid substitution were observed in the cohort with vascular damage. Therefore, fast diagnosis and early interventional and surgical procedures are necessary to optimize patient-specific outcome. KW - endovascular repair KW - extremity trauma KW - fracture-associated vascular damage KW - level of evidence: IV KW - surgical trauma room KW - pelvic trauma Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176252 VL - 19 IS - 404 ER - TY - JOUR A1 - Gilbert, F. A1 - Meffert, R. H. A1 - Schmalzl, J. A1 - Weng, A. M. A1 - Köstler, H. A1 - Eden, L. T1 - Grade of retraction and tendon thickness correlates with MR-spectroscopically measured amount of fatty degeneration in full thickness supraspinatus tears JF - BMC Musculoskeletal Disorders N2 - Background: The amount of fatty degeneration (FD) has major impact on the clinical result and cuff integrity after rotator cuff repair. A quantitative analysis with magnet resonance imaging (MRI) spectroscopy was employed to analyze possible correlation of FD with tendon retraction, tendon thickness and patients’ characteristics in full thickness supraspinatus tears. Methods: Forty-two patients with full-thickness supraspinatus tears underwent shoulder MRI including an experimental spectroscopic sequence allowing quantification of the fat fraction in the supraspinatus muscle belly. The amount of fatty degeneration was correlated with tendon retraction, tendon thickness, patients’ age, gender, smoker status, symptom duration and body mass index (BMI). Patients were divided in to three groups of retraction (A) 0-10 mm (n=), (B) 11-20 mm (n=) and (C) < 21 mm (n=) and the means of FD for each group were calculated. Results: Tendon retraction (R = 0.6) and symptom duration (R = 0.6) correlated positively, whereas tendon thickness correlated negatively (R = − 0.6) with the amount of FD. The fat fraction increased significantly with tendon retraction: Group (A) showed a mean fat mount of 3.7% (±4%), group (B) of 16.7% (±8.2%) and group (C) of 37.5% (±19%). BMI, age and smoker-status only showed weak to moderate correlation with the amount of FD in this cohort. Conclusion: MRI spectroscopy revealed significantly higher amount of fat with increasing grade of retraction, symptom duration and decreased tendon thickness. Thus, these parameters may indirectly be associated with the severity of tendon disease. KW - rotator cuff KW - MRI KW - spectroscopy KW - muscle degeneration Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176116 VL - 19 IS - 197 ER - TY - JOUR A1 - Gilbert, F. A1 - Heintel, T. M. A1 - Jakubietz, M. G. A1 - Köstler, H. A1 - Sebald, C. A1 - Meffert, R. H. A1 - Weng, A. M. T1 - Quantitative MRI comparison of multifidus muscle degeneration in thoracolumbar fractures treated with open and minimally invasive approach JF - BMC Musculoskeletal Disorders N2 - Background: Minimally invasive pedicle screw fixation has less approach-related morbidity than open screw placement and is allegedly less traumatizing on paravertebral muscles, as there is no requirement to mobilize and retract the adjacent muscle portion. The approach-related long-term effects to the morphology of the paravertebral muscles are unknown. The purpose of this study was to compare the long-term amount of fatty degeneration of the multifidus muscle in patients treated with a classical open or a minimally invasive approach. Methods: Fourteen Patients meeting inclusion criteria were selected. In all patients a singular fracture of the thoracolumbar spine with a two-level posterior instrumentation was treated, either using an open approach or a minimally invasive approach. All patients underwent quantitative MRI spectroscopy for quantification of the fatty degeneration in the multifidus muscle as a long-term proof for muscle loss after minimum 4-year follow-up. Clinical outcome was assessed using Oswestry Low Back Pain Disability Questionnaire, SF-36 and VA-scale for pain. Results: The minimally invasive approach group failed to show less muscle degeneration in comparison to the open group. Total amount of fatty degeneration was 14.22% in the MIS group and 12.60% in the open group (p = 0.64). In accordance to MRI quantitative results there was no difference in the clinical outcome after a mean follow up of 5.9 years (±1.8). Conclusion: As short-term advantages of minimal invasive screw placement have been widely demonstrated, no advantage of the MIS, displaying a significant difference in the amount of fatty degeneration and resulting in a better clinical outcome could be found. Besides the well-known short-term advantage of minimally invasive pedicle screw placement, a long-term advantage, such as less muscle degeneration and thus superior clinical results, compared to the open approach could not be shown. KW - dorsal instrumentation KW - minimal invasive surgery KW - muscle degeneration KW - spine trauma Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175742 VL - 19 IS - 75 ER - TY - JOUR A1 - Gietzen, Carsten Herbert A1 - Kunz, Andreas Steven A1 - Luetkens, Karsten Sebastian A1 - Huflage, Henner A1 - Christopoulos, Georgios A1 - van Schoonhoven, Jörg A1 - Bley, Thorsten Alexander A1 - Schmitt, Rainer A1 - Grunz, Jan-Peter T1 - Evaluation of prestyloid recess morphology and ulnar-sided contrast leakage in CT arthrography of the wrist JF - BMC Musculoskeletal Disorders N2 - Background In wrist arthrograms, aberrant contrast material is frequently seen extending into the soft tissue adjacent to the ulnar styloid process. Since the prestyloid recess can mimic contrast leakage in CT arthrography, this study aims to provide a detailed analysis of its morphologic variability, while investigating whether actual ulnar-sided leakage is associated with injuries of the triangular fibrocartilage complex (TFCC). Methods Eighty-six patients with positive wrist trauma history underwent multi-compartment CT arthrography (40 women, median age 44.5 years). Studies were reviewed by two board-certified radiologists, who documented the morphology of the prestyloid recess regarding size, opening type, shape and position, as well as the presence or absence of ulnar-sided contrast leakage. Correlations between leakage and the presence of TFCC injuries were assessed using the mean square contingency coefficient (r\(_{ɸ}\)). Results The most common configuration of the prestyloid recess included a narrow opening (73.26%; width 2.26 ± 1.43 mm), saccular shape (66.28%), and palmar position compared to the styloid process (55.81%). Its mean length and anterior–posterior diameter were 6.89 ± 2.36 and 5.05 ± 1.97 mm, respectively. Ulnar-sided contrast leakage was reported in 29 patients (33.72%) with a mean extent of 12.30 ± 5.31 mm. Leakage occurred more often in patients with ulnar-sided TFCC injuries (r\(_{ɸ}\) = 0.480; p < 0.001), whereas no association was found for lesions of the central articular disc (r\(_{ɸ}\) = 0.172; p = 0.111). Conclusions Since ulnar-sided contrast leakage is more common in patients with peripheral TFCC injuries, distinction between an atypical configuration of the prestyloid recess and actual leakage is important in CT arthrography of the wrist. KW - prestyloid recess KW - arthrography KW - tomography KW - x-ray computed KW - triangular fibrocartilage complex Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301113 VL - 23 IS - 1 ER - TY - JOUR A1 - Gerhard-Hartmann, Elena A1 - Wiegering, Verena A1 - Benoit, Clemens A1 - Meyer, Thomas A1 - Rosenwald, Andreas A1 - Maurus, Katja A1 - Ernestus, Karen T1 - A large retroperitoneal lipoblastoma as an incidental finding: a case report JF - BMC Pediatrics N2 - Background Lipoblastoma is a rare benign mesenchymal neoplasm of infancy that most commonly occurs on the extremities and trunk but can arise at variable sites of the body. Retroperitoneal lipoblastomas are particularly rare but can grow to enormous size, and preoperative diagnosis is difficult with diverse, mostly malignant differential diagnoses that would lead to aggressive therapy. Since lipoblastoma is a benign tumor that has an excellent prognosis after resection, correct diagnosis is crucial. Case presentation A case of a large retroperitoneal tumor of a 24-month old infant that was clinically suspicious of a malignant tumor is presented. Due to proximity to the right kidney, clinically most probably a nephroblastoma or clear cell sarcoma of the kidney was suspected. Radiological findings were ambiguous. Therefore, the mass was biopsied, and histology revealed an adipocytic lesion. Although mostly composed of mature adipocytes, in view of the age of the patient, the differential diagnosis of a (maturing) lipoblastoma was raised, which was supported by molecular analysis demonstrating a HAS2-PLAG1 fusion. The tumor was completely resected, and further histopathological workup led to the final diagnosis of a 13 cm large retroperitoneal maturing lipoblastoma. The child recovered promptly from surgery and showed no evidence of recurrence so far. Conclusion Although rare, lipoblastoma should be included in the differential diagnoses of retroperitoneal tumors in infants and children, and molecular diagnostic approaches could be a helpful diagnostic adjunct in challenging cases. KW - retroperitoneal tumor KW - pediatric KW - lipoblastoma KW - PLAG1 rearrangement KW - case report Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260173 VL - 21 ER - TY - THES A1 - Gemeinhardt, Katharina Christine T1 - Magnetresonanztomographie und -spektroskopie der Schulter nach Latissimus-dorsi-Transfer unter Berücksichtigung von Sehnenintegrität, Atrophie und fettiger Degeneration der Rotatorenmanschette T1 - Magnetic resonance tomography and spectroscopy of the shoulder N2 - Darstellung des Latissimus-dorsi-Transfers mit Hilfe des MRTs. Quantifizierung der fettigen Degeneration mit Hilfe der semiquantitativen Methode nach Goutailler und der 2D-SPLASH-Sequenz. N2 - Magnetic resonance tomography and spectroscopy of the shoulder, fatty degeneration and atrophy after rotator cuff tear KW - NMR-Tomographie KW - Breiter Rückenmuskel KW - Rotatorenmanschette KW - Atrophie KW - Fett KW - 2D-SPLASH KW - Spektroskopie KW - 2D-SPLASH Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-28035 ER - TY - JOUR A1 - Geiger, Julia A1 - Hirtler, Daniel A1 - Gottfried, Kristina A1 - Rahman, Ozair A1 - Bollache, Emilie A1 - Barker, Alex J. A1 - Markl, Michael A1 - Stiller, Brigitte T1 - Longitudinal Evaluation of Aortic Hemodynamics in Marfan Syndrome: New Insights from a 4D Flow Cardiovascular Magnetic Resonance Multi-Year Follow-Up Study JF - Journal of Cardiovascular Magnetic Resonance N2 - Background The aim of this 4D flow cardiovascular magnetic resonance (CMR) follow-up study was to investigate longitudinal changes in aortic hemodynamics in adolescent patients with Marfan syndrome (MFS). Methods 4D flow CMR for the assessment of in-vivo 3D blood flow with full coverage of the thoracic aorta was performed twice (baseline scan t1/follow-up scan t2) in 19 adolescent MFS patients (age at t1: 12.7 ± 3.6 years, t2: 16.2 ± 4.3 years) with a mean follow-up duration of 3.5 ± 1.2 years. Ten healthy volunteers (24 ± 3.8 years) served as a control group. Data analysis included aortic blood flow visualization by color-coded 3D pathlines, and grading of flow patterns (helices/vortices) on a 3-point scale (none, moderate, severe; blinded reading, 2 observers). Regional aortic peak systolic velocities and systolic 3D wall shear stress (WSS) along the entire aortic wall were quantified. Z-Scores of the aortic root and proximal descending aorta (DAo) were assessed. Results Regional systolic WSS was stable over the follow-up duration, except for a significant decrease in the proximal inner DAo segment (p = 0.02) between t1 and t2. MFS patients revealed significant lower mean systolic WSS in the proximal inner DAo compared with volunteers (0.78 ± 0.15 N/m\(^{2}\)) at baseline t1 (0.60 ± 0.18 N/m\(^{2}\); p = 0.01) and follow-up t2 (0.55 ± 0.16 N/m\(^{2}\); p = 0.001). There were significant relationships (p < 0.01) between the segmental WSS in the proximal inner DAo, DAo Z-scores (r = −0.64) and helix/vortex pattern grading (r = −0.55) at both t1 and t2. The interobserver agreement for secondary flow patterns assessment was excellent (Cohen’s k = 0.71). Conclusions MFS patients have lower segmental WSS in the inner proximal DAo segment which correlates with increased localized aberrant vortex/helix flow patterns and an enlarged diameter at one of the most critical sites for aortic dissection. General aortic hemodynamics are stable but these subtle localized DAo changes are already present at young age and tend to be more pronounced in the course of time. KW - Marfan syndrome KW - wall shear stress KW - hemodynamics KW - 4D flow cardiovascular magnetic resonance KW - follow-up KW - aorta Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171119 VL - 19 IS - 33 ER - TY - JOUR A1 - Gassenmaier, Tobias A1 - Petritsch, Bernhard A1 - Kunz, Andreas S. A1 - Gkaniatsas, Spyridon A1 - Gaudron, Philipp D. A1 - Weidemann, Frank A1 - Nordbeck, Peter A1 - Beer, Meinrad T1 - Long term evolution of MRI characteristics in a case of atypical left lateral wall hypertrophic cardiomyopathy JF - World Journal of Cardiology N2 - We are reporting a long-time magnetic resonance imaging (MRI) follow-up in a rare case of cardiac left lateral wall hypertrophy. Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiovascular disorder and a significant cause of sudden cardiac death. Cardiac magnetic resonance (CMR) imaging can be a valuable tool for assessment of detailed information on size, localization, and tissue characteristics of hypertrophied myocardium. However, there is still little knowledge of long-term evolution of HCM as visualized by magnetic resonance imaging. Recently, our group reported a case of left lateral wall HCM as a rare variant of the more common forms, such as septal HCM, or apical HCM. As we now retrieved an old cardiac MRI acquired in this patient more than 20 years ago, we are able to provide the thrilling experience of an ultra-long MRI follow-up presentation in this rare case of left lateral wall hypertrophy. Furthermore, this case outlines the tremendous improvements in imaging quality within the last two decades of CMR imaging. KW - cardiac magnetic resonance imaging KW - hypertrophic cardiomyopathy KW - follow-up KW - atypical KW - left lateral wall Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124934 VL - 7 IS - 6 ER - TY - JOUR A1 - Gassenmaier, Tobias A1 - Gorski, Armin A1 - Aleksic, Ivan A1 - Deubner, Nikolas A1 - Weidemann, Frank A1 - Beer, Meinrad T1 - Impact of cardiac magnet resonance imaging on management of ventricular septal rupture after acute myocardial infarction JF - World Journal of Cardiology N2 - A 74-year-old man was admitted to the cardiac catheterization laboratory with acute myocardial infarction. After successful angioplasty and stent implantation into the right coronary artery, he developed cardiogenic shock the following day. Echocardiography showed ventricular septal rupture. Cardiac magnet resonance imaging (MRI) was performed on the critically ill patient and provided detailed information on size and localization of the ruptured septum by the use of fast MRI sequences. Moreover, the MRI revealed that the ventricular septal rupture was within the myocardial infarction area, which was substantially larger than the rupture. As the patient’s condition worsened, he was intubated and had intra-aortic balloon pump implanted, and extracorporeal membrane oxygenation was initiated. During the following days, the patient’s situation improved, and surgical correction of the ventricular septal defect could successfully be performed. To the best of our knowledge, this case report is the first description of postinfarction ventricular septal rupture by the use of cardiac MRI in an intensive care patient with cardiogenic shock and subsequent successful surgical repair. KW - Cardiac magnetic resonance imaging KW - Ventricular septal rupture KW - Myocardial infarction KW - surgical repair KW - Extracorporeal membrane oxygenation Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-96562 ER - TY - THES A1 - Gasparyan, Artur T1 - Quantifizierung pulmonaler Blutflussgeschwindigkeit durch SENCEFUL Magnetresonanztomographie mit bewegter Schichtselektion T1 - Quantification of pulmonary blood flow velocity through SENCEFUL magnetic resonance imaging using moving slice selection N2 - Patienten mit chronischen Lungenerkrankungen leiden unter schwerwiegender Symptomatik und bedürfen regelmäßiger Verlaufskontrollen der Therapie. Dabei sollte zum Schutz der Patienten sowohl auf kanzerogene, ionisierende Strahlung verzichtet als auch der Einsatz potenziell nebenwirkungsreicher Kontrastmittel vermieden werden. Die pulmonale Blutflussgeschwindigkeit im Parenchym stellt einen quantitativen, bildgebenden Biomarker dar, mit dessen Hilfe die Dynamik des Krankheitsgeschehens untersucht werden kann. In dieser Arbeit wurde eine neue Auswertungsmethode vorgestellt, die mit Hilfe kontrastmittelfreier Magnetresonanztomographie die Blutflussgeschwindigkeit im Lungenparenchym quantifizieren kann. Die auf diese Weise bestimmten Ergebnisse entsprechen den Angaben zur Lungenperfusion, wie sie in der Literatur zu finden sind. N2 - Patients with chronic respiratory diseases suffer from severe symptoms and require regular follow ups during treatment. It is important to avoid the use of cancerogenic ionising radiation as well as potentially harmful contrast agents. The pulmonary blood flow velocity within the parenchyma can serve as a quantitative imaging biomarker, which can help analyse the course of the disease. In this work a new method for the quantification of pulmonary blood flow velocity is shown. The results correspond to physiological values in the human lung. KW - Kernspintomografie KW - Lunge KW - Blutflussgeschwindigkeit KW - Quantitativ Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-215693 ER - TY - THES A1 - Fuchs, Kilian T1 - Absolutquantifizierung der myokardialen Perfusion mit hochauflösender MRT bei 3 Tesla T1 - Absolute Quantification of Myocardial Perfusion Using High-Resolution MRI at 3 T N2 - In den letzten Jahren hat die myokardiale MR-Perfusionsbildgebung als nichtinvasives Verfahren zur Darstellung von funktionellen Veränderungen des Myokards für die Diagnostik der KHK zunehmend an Bedeutung gewonnen. Während in den letzten 20 Jahren die kardiale MRT überwiegend bei einer Magnetfeldstärke von 1,5 T durchge-führt wurde und dies auch immer noch wird, findet aktuell eine rasante Verbreitung von MR-Systemen höherer Feldstärken statt. Von der neuen Hochfeldtechnik erhofft man sich vor allem, je nach Anwendung, eine deutliche Verbesserung der Bildqualität mit höherer räumlicher und zeitlicher Auflösung, wodurch der diagnostische Nutzen noch weiter gesteigert werden könnte. In der vorliegenden Arbeit wurden mittels First-Pass-MR-Bildgebung bei einer Magnet-feldstärke von 3 T quantitative Werte für die myokardiale Perfusion von 20 gesunden Probanden unter Ruhebedingungen bestimmt. Sowohl die erhobenen absoluten Perfusionswerte (0,859 ml/g/min im Mittel) als auch die Standardabweichung des mittleren MBF (0,298 ml/g/min) entsprechen den Messungen aus den früheren Publikationen dieser Arbeitsgruppe. In der Gesamtzusammenschau bisher veröffentlichter Perfusionsstudien zeigt sich eine relativ große Variabilität der publizierten Ruheflüsse. Dabei liegt der absolute MBF dieser Arbeit im mittleren Wertebereich dieser Streubreite. Er lässt sich auch mit den in PET-Studien ermittelten Ergebnissen in Einklang bringen, welche als Goldstandard zur Bestimmung der absoluten myokardialen Perfusion beim Menschen gelten. Die vorliegende Arbeit bestätigt die bereits in anderen 3 T-Studien untersuchten Vorteile der Hochfeld-MRT. Die höhere Magnetfeldstärke ermöglicht durch das größere SNR eine signifikant bessere räumliche Auflösung und besticht vor allem durch die hohe Bildqualität. Dies könnte bei der Erkennung kleiner, subendokardial gelegener Perfusionsdefekte sowie der Erstellung von transmuralen Perfusionsgradienten von Bedeutung sein und verspricht neben einer Reduktion von Partialvolumeneffekten auch eine Verminderung von „dark rim“-Artefakten. Um diese Vorteile entsprechend nutzen zu können, wird die Entwicklung von Methoden zur pixelweisen Bestimmung der absoluten Flüsse und farblich kodierten Darstellung derselben in Form von Perfusionskarten ein weiterer Schritt in Richtung klinisch einsetzbare Diagnostik sein. Eine Voraussetzung hierfür ist die Entwicklung einer exakten und sehr stabilen Bewegungskorrektur in weiterführenden Studien. Durch den Wechsel zu einer höheren Magnetfeldstärke von 3 T und den sich daraus ergebenden Vorteilen kann das Potential der MR-Perfusionsbildgebung, insbesondere der Bestimmung quantitativer Perfusionswerte, im Bereich der nichtinvasiven KHK-Diagnostik zukünftig weiter gesteigert werden. N2 - Absolute Quantification of Myocardial Perfusion Using High-Resolution MRI at 3 T KW - Kernspintomographie KW - Perfusion KW - Feldstärke KW - Quantifizierung KW - Absolutquantifizierung KW - myokardiale Perfusion KW - 3 Tesla KW - Hochfeld KW - Magnetresonanztomographie Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-107015 ER - TY - THES A1 - Fuchs, Jan Christopher T1 - Quantitative MR-Spektroskopie des menschlichen Herzens mittels CORRECT-SLIM T1 - Quantitative mr-spectroscopy of the human heart by CORRECT-SLIM N2 - Die 31P-MRS ermöglicht die nicht-invasive Untersuchung des kardialen Energiestoffwechsels sowie die Absolutquantifizierung der Metaboliten des kardialen Energiestoffwechsels. Mit dem schnellen Siegeszug der MR-Bildgebung in der klinischen Routine im Bereich kardiologischer Fragestellungen konnte die MRS bis in die heutige Zeit hinein jedoch nicht Schritt halten. Bedingt durch technische Limitationen konnte der Einsatz der MR-Spektroskopie des menschlichen Herzens hier bisher noch nicht Fuß fassen. Eine Weiterentwicklung mit dem Ziel der Etablierung der MRS in der klinischen Routine würde der Medizin neue Wege in Diagnostik und Patientenmonitoring ermöglichen. So wäre die Entwicklung eines kombinierten MRI/MRS-Protokolles für ein kardiales Langzeitmonitoring bei Kindern/Jugendlichen sowie bei erwachsenen Patienten mit unterschiedlichen Herzerkrankungen eine lohnende Aufgabe. Nur sehr wenige Arbeiten konnten bisher Ergebnisse zum Energiestoffwechsel und den Verhältnissen und Konzentration im rechten Ventrikel liefern. Durch die Entwicklung eines verbesserten Auswertealgorithmus (CORRECT-SLIM) am Institut für Röntgendiagnostik der Universität Würzburg könnten nun erstmals neue Aussagen hierzu möglich werden. Mit CORRECT-SLIM stellen wir erstmals ein Verfahren zur Absolutquantifizierung vor, das die Kontamination des Myokards des linken und rechten Ventrikel aus Brustwandarealen reduziert. Das Ziel der vorliegenden Arbeit war es, das neue Auswerteverfahren CORRECT-SLIM (Contamination Reduction in the Reconstruction with Spectral Localization by Imaging) systematisch sowohl am linken als auch am rechten Ventrikel des Herzens anzuwenden um hierdurch neue Aussagen zum Energiestoffwechsel des gesamten Herzens zu erhalten bzw. die Entwicklung und Verbesserung der bisherigen Auswerteverfahren (SLOOP) im Bereich der 31P-MRS Untersuchungen voranzutreiben. Hierzu wurden spektroskopische Untersuchungen am Myokard gesunder und kardial erkrankter Probanden durchgeführt. Die kardial erkrankten Patienten wiesen alle eine Hypertrophie des linken und/oder rechten Ventrikels auf, womit ein für die spektroskopische Auswertung erhöhtes Volumen zur Verfügung stand, was gerade im Hinblick auf die geringe physiologische Wandstärke des rechten Ventrikels erwünscht war und die Festlegung der Segmentationsgrenzen erleichterte. N2 - 31P-MRS allows the non-invasive examination of the cardiac high-energy phosphate metabolism and furthermore the absolute quantification of the high-energy phosphor metabolites. Due to the rapid progress of the MR imaging techniques and applications in the field of cardiology it is now used as a common instrument in the all-day clinical routine. Despite of it’s rapid progress in the field of the cardiac imaging techniques the 31P-MRS couldn’t be integrated into the clinical routine until today, due to technical limitations. Integration and development of the 31P-MRS technique in the clinical routine could offer new possibilities in diagnostic approaches and patient monitoring. The development of a combined MRI/31P-MRS-protocol for a cardiovascular long-time monitoring of cardiac diseases could be of great benefit. Only few publications concerning the energy metabolism of the right human cardiac ventricle have been made until today. By the development of a new evaluation- and quantification-algorithm (CORRECT-SLIM) new findings could be possible. With CORRECT-SLIM we introduce a new method for the absolute quantification of cardiac high-energy phosphates. It reduces the contamination of the left and right ventricle signal by the skeletal-muscle of the chest wall. The aim of the following study was to evaluate the CORRECT-SLIM algorithm (Contamination Reduction in the Reconstruction with Spectral Localization by Imaging) systematically for the cardiac high-energy metabolism of the left as well as for the right ventricle of the human heart and compare it to other evaluation/quantification-methods (SLOOP). The spectroscopic analysis involved the left and right ventricle of healthy volunteers and patients with hypertrophic heart disease as well as severe aortic stenosis. KW - Phosphor-31-NMR-Spektroskopie KW - Herzstoffwechsel KW - Quantifizierung KW - 31P-MRS KW - MR-Spektroskopie KW - Absolutquantifizierung KW - Phosphormetaboliten KW - mrs KW - cardiac spectroscopy KW - high-energy-phosphate metabolism Y1 - 2010 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-49005 ER - TY - JOUR A1 - Fröhlich, Matthias A1 - Serfling, Sebastian A1 - Higuchi, Takahiro A1 - Pomper, Martin G. A1 - Rowe, Steven P. A1 - Schmalzing, Marc A1 - Tony, Hans-Peter A1 - Gernert, Michael A1 - Strunz, Patrick-Pascal A1 - Portegys, Jan A1 - Schwaneck, Eva-Christina A1 - Gadeholt, Ottar A1 - Weich, Alexander A1 - Buck, Andreas K. A1 - Bley, Thorsten A. A1 - Guggenberger, Konstanze V. A1 - Werner, Rudolf A. T1 - Whole-Body [\(^{18}\)F]FDG PET/CT Can Alter Diagnosis in Patients with Suspected Rheumatic Disease JF - Diagnostics N2 - The 2-deoxy-d-[\(^{18}\)F]fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) is widely utilized to assess the vascular and articular inflammatory burden of patients with a suspected diagnosis of rheumatic disease. We aimed to elucidate the impact of [\(^{18}\)F]FDG PET/CT on change in initially suspected diagnosis in patients at the time of the scan. Thirty-four patients, who had undergone [\(^{18}\)F]FDG PET/CT, were enrolled and the initially suspected diagnosis prior to [18F]FDG PET/CT was compared to the final diagnosis. In addition, a semi-quantitative analysis including vessel wall-to-liver (VLR) and joint-to-liver (JLR) ratios was also conducted. Prior to [\(^{18}\)F]FDG PET/CT, 22/34 (64.7%) of patients did not have an established diagnosis, whereas in 7/34 (20.6%), polymyalgia rheumatica (PMR) was suspected, and in 5/34 (14.7%), giant cell arteritis (GCA) was suspected by the referring rheumatologists. After [\(^{18}\)F]FDG PET/CT, the diagnosis was GCA in 19/34 (55.9%), combined GCA and PMR (GCA + PMR) in 9/34 (26.5%) and PMR in the remaining 6/34 (17.6%). As such, [\(^{18}\)F]FDG PET/CT altered suspected diagnosis in 28/34 (82.4%), including in all unclear cases. VLR of patients whose final diagnosis was GCA tended to be significantly higher when compared to VLR in PMR (GCA, 1.01 ± 0.08 (95%CI, 0.95–1.1) vs. PMR, 0.92 ± 0.1 (95%CI, 0.85–0.99), p = 0.07), but not when compared to PMR + GCA (1.04 ± 0.14 (95%CI, 0.95–1.13), p = 1). JLR of individuals finally diagnosed with PMR (0.94 ± 0.16, (95%CI, 0.83–1.06)), however, was significantly increased relative to JLR in GCA (0.58 ± 0.04 (95%CI, 0.55–0.61)) and GCA + PMR (0.64 ± 0.09 (95%CI, 0.57–0.71); p < 0.0001, respectively). In individuals with a suspected diagnosis of rheumatic disease, an inflammatory-directed [\(^{18}\)F]FDG PET/CT can alter diagnosis in the majority of the cases, particularly in subjects who were referred because of diagnostic uncertainty. Semi-quantitative assessment may be helpful in establishing a final diagnosis of PMR, supporting the notion that a quantitative whole-body read-out may be useful in unclear cases. KW - giant cell arteritis KW - GCA KW - [18F]FDG PET/CT KW - vasculature KW - inflammation KW - polymyalgia rheumatica KW - PMR KW - vasculitis Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-250227 SN - 2075-4418 VL - 11 IS - 11 ER - TY - THES A1 - Fritz, Dorothée Ulrike T1 - Retrospektive Analyse der computertomographisch gesteuerten Punktionen an einem Kollektiv von 951 Patienten T1 - Retrospective review of CT-guided biopsies performed on 951 patients N2 - Ziel dieser Arbeit war es, den Stellenwert der CT-gesteuerten Punktion hinsichtlich Komplikationsrate, nicht auswertbaren Biopsien, deren statistische Kenngrößen in der Gesamtheit und deren Zusammenhang bezüglich Nadelgröße, Punktionsweg und Läsionsgröße zu ermitteln. Insgesamt konnte retrospektiv ein Kollektiv von 1019 Punktionen an 951 Patienten im Institut für Röntgendiagnostik der Universität Würzburg mit einem Follow-up von 2 Jahren untersucht werden. Es konnten in 96 % der Fälle vom Pathologen auswertbare Proben gewonnen werden. Bei 951 Patienten konnten 38 Biopsien nicht histologisch ausgewertet werden. Es bestand ein signifikanter Zusammenhang bezüglich der Dicke der Biopsienadel und der histologischen Auswertbarkeit. 19/20 G Nadeln führten in 20 % der Fälle zu nicht beurteilbaren Proben, 15/16 G und 17/18 G Nadeln hingegen nur bei 1,8 % und 3,6 % der Punktionen. Bei komplikationslosen Punktionen ergaben sich seltener histologisch nicht auswertbare Proben (3,5 %) als bei Biopsien, die eine Komplikation verursachten bzw. nach sich zogen (6,3 %). Die Biopsien fanden in 57 % der Fälle mit 17/18 G Nadeln statt. Bei 40 % der Punktionen wurden 15/16 G Nadeln verwendet. In lediglich 4,3 % und 6,7 % der Fälle kamen 19/20 G Nadeln und Knochenstanzen zum Einsatz. In der Gesamtheit des Kollektivs ergab sich eine Sensitivität von 92 % bei einer Spezifität von 100 %. Die Kenngrößen variierten in den anatomischen Subgruppen. Von 951 Punktionen erwiesen sich 6,8 % als falsch negativ, 73,2 % als richtig positiv und 16,7 % als richtig negativ. 58 Bei Pankreas-Punktionen lag die falsch negativ Rate mit 23,1 % am höchsten. Niedrige falsch negativ Raten zeigten sich bei Pleura- (2,9 %), Lungen- (5,3 %) und Muskel-/Weichteilpunktionen (1,5 %). Als signifikant erwies sich der Zusammenhang zwischen Biopsienadelgröße und histologischem Ergebnis. Falsch negative Ergebnisse waren besonders bei Anwendungen von 19/20 G Nadeln zu verzeichnen (17,5 %). Bei 17/18 G Nadeln und Knochenstanzen traten insgesamt nur in 7,5 % und 7,9 % falsch negative Ergebnisse auf. Der Durchmesser der Läsion beeinflusste signifikant das histologische Ergebnis. Bei falsch negativen Ergebnissen betrug der Durchmesser im Mittelwert 3,4 cm. Bei richtig positiven Punktionen lag der Läsionsdurchmesser bei 4,1 cm. In 18,4 % der Fälle führte eine Probeentnahme zu einer Komplikation. Davon erwiesen sich 14,8 % als Minor- und 3,6 % als Majorkomplikation, wie zum Beispiel ein Pneumothorax mit Notwendigkeit einer Drainagelegung. Die meisten Komplikationen traten bei Punktionen der Lunge (14 %) auf. Dabei zeigten die Nadeln 19/20 G mit 40 % die höchste Komplikationsrate. Dies ist nicht der Tatsache geschuldet, dass die dünneren Nadeln vorwiegend bei tiefen Läsionen zum Einsatz kamen. Auch bei tieferen Punktionen ist die Komplikationsrate der dickeren Nadeln geringer, als die der dünnen. 15/16 G Nadeln kamen bei einer durchschnittlichen Tiefe von 5,6 cm zum Einsatz, 17/18 G Nadeln bei 6,6 cm und 19/20 G Nadeln bei 7,2 cm. Betrachtet man jedoch die Nadelgruppen 17/18 G und 19/20 G für sich, zeigte sich, dass der Abstand zur Haut bei Komplikationen nicht größer war, als ohne Komplikation. Bei 15/16 G Nadeln war der Punktionsweg bei Komplikationen signifikant größer als bei Punktionen ohne Komplikation. Bei Lungenpunktionen im Speziellen war der Punktionsweg ebenfalls für 15/16 G länger, wenn ein Pneumothorax aufgetreten ist, als bei komplikationslosen Biopsien. 59 Es zeigte sich, dass bei Wiederholungspunktionen die Läsionen tiefer lagen, als bei einmaligen Punktionen. Die Läsionsgröße lag durchschnittlich bei 4 cm. Beim Auftreten einer Komplikation erwies sich der Durchmesser der Läsion, besonders für Lungenbiopsien, als signifikant kleiner (MV = 3,5), als bei komplikationslosen Biopsien. Ein wichtiger Faktor für die Treffsicherheit, den positiven Vorhersagewert und die Komplikationsrate spielte die Erfahrung des jeweiligen Punkteurs. Diese Arbeit konnte belegen, dass der Radiologe mit 20 Jahren Erfahrung die niedrigste Komplikationsrate (15 %) und gleichzeitig die geringste falsch negativ Rate (12 %) hatte. N2 - Purpose: The CT-guided biopsy is a well-established technique for the diagnosis of unknown lesions. The objective of this study was to evaluate the diagnostic accuracy of CT-guided biopsies, in the context of needle size, complication rate, lesion size and the radiologists experience in a representative number of patients. Method: The results of 1019 CT-guided biopsies in 951 patients were evaluated with regard to sensitivity, specificity and complication rate of the chosen needle sizes. A 17/18 g needle was used in 544 cases, a 19/20 g needle in 40 cases and a 15/16 g needle was used in 351 cases. Lesion size, depth and location were included as variables. Results: The biopsies yielded sufficient histology material in 913 of 951 (96%) cases. The rate of insufficient histology material increased significantly when a smaller needle size was used (20% when a 19/20 g needle was used). The false negative rate (6,8%) was influenced by needle size (17,5% at 19/29 g) and lesion size. Overall the sensitivity, specificity and diagnostic accuracy were 92%, 100% and 93%. Complications were noted in 18,4% of all cases. The most major-complication was pneumothorax (3%), which required chest tube drainages. Conclusion: With 15/16 g and 17/18 G needle sizes, diagnostic accuracy can be drastically increased without an increase in the complication rate. KW - Computertomograph KW - Punktion KW - Diagnostik KW - Komplikation KW - CT-gesteuerte Punktion KW - Maligne Tumoren KW - Raumforderung KW - Stanzbiopsie KW - Pneumothorax Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126347 ER - TY - JOUR A1 - Frey, Anna A1 - Gassenmaier, Tobias A1 - Hofmann, Ulrich A1 - Schmitt, Dominik A1 - Fette, Georg A1 - Marx, Almuth A1 - Heterich, Sabine A1 - Boivin-Jahns, Valérie A1 - Ertl, Georg A1 - Bley, Thorsten A1 - Frantz, Stefan A1 - Jahns, Roland A1 - Störk, Stefan T1 - Coagulation factor XIII activity predicts left ventricular remodelling after acute myocardial infarction JF - ESC Heart Failure N2 - Aims Acute myocardial infarction (MI) is the major cause of chronic heart failure. The activity of blood coagulation factor XIII (FXIIIa) plays an important role in rodents as a healing factor after MI, whereas its role in healing and remodelling processes in humans remains unclear. We prospectively evaluated the relevance of FXIIIa after acute MI as a potential early prognostic marker for adequate healing. Methods and results This monocentric prospective cohort study investigated cardiac remodelling in patients with ST-elevation MI and followed them up for 1 year. Serum FXIIIa was serially assessed during the first 9 days after MI and after 2, 6, and 12 months. Cardiac magnetic resonance imaging was performed within 4 days after MI (Scan 1), after 7 to 9 days (Scan 2), and after 12 months (Scan 3). The FXIII valine-to-leucine (V34L) single-nucleotide polymorphism rs5985 was genotyped. One hundred forty-six patients were investigated (mean age 58 ± 11 years, 13% women). Median FXIIIa was 118 % (quartiles, 102–132%) and dropped to a trough on the second day after MI: 109%(98–109%; P < 0.001). FXIIIa recovered slowly over time, reaching the baseline level after 2 to 6 months and surpassed baseline levels only after 12 months: 124 % (110–142%). The development of FXIIIa after MI was independent of the genotype. FXIIIa on Day 2 was strongly and inversely associated with the relative size of MI in Scan 1 (Spearman’s ρ = –0.31; P = 0.01) and Scan 3 (ρ = –0.39; P < 0.01) and positively associated with left ventricular ejection fraction: ρ = 0.32 (P < 0.01) and ρ = 0.24 (P = 0.04), respectively. Conclusions FXIII activity after MI is highly dynamic, exhibiting a significant decline in the early healing period, with reconstitution 6 months later. Depressed FXIIIa early after MI predicted a greater size of MI and lower left ventricular ejection fraction after 1 year. The clinical relevance of these findings awaits to be tested in a randomized trial. KW - blood coagulation factor XIII KW - ST-elevation myocardial infarction KW - healing and remodelling processes KW - cardiac magnetic resonance imaging Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236013 VL - 7 IS - 5 ER - TY - THES A1 - Fischer, Monika T1 - Nicht operierte Sagittalnahtsynostosen im Verlauf T1 - Radiographic Changes in Non-Operated Sagittal Suture Synostosis N2 - Zur Darstellung des Verlaufs bei nicht operierten Kindern mit Sagittalsynostose wurden 155 Röntgenbilder von 52 Patienten im Alter zwischen 15 Tagen und 9 Jahren untersucht. Die Schädelnähte wurden hinsichtlich der Darstellbarkeit, Begrenzung, Zähnelung und Aktivität beurteilt. Weiterhin wurden acht Strecken und vier Winkel gemessen, daraus zwei Indizes berechnet. Die Sagittalnaht war bei mehr als der Hälfte der Aufnahmen im ersten Lebensjahr partiell bzw. vollständig darstellbar. Die Lambdanaht war ab dem zweiten Lebensmonat immer, die Coronarnaht bis auf wenige Ausnahmen darstellbar. Die Zähnelung der Nähte entwickelte sich altersentsprechend. Der Anteil der Nähte, die keine erhöhte Aktivität aufwiesen, sank im Verlauf von 94% auf 38%. Bei den Messstrecken und Winkeln wurden die Ergebnisse aus der Literatur weitgehend bestätigt. Der Basiswinkel war im untersuchten Patientenkollektiv signifikant erhöht. Der Höhenindex näherte sich im Verlauf der Altersnorm an, wohingegen sich die Parameter innere Schädelbreite und Breiten-Längen-Index signifikant von der Altersnorm entfernten. Der Skaphozephalus wächst sich nicht aus, aber einzelne Merkmale, wie die parietale Wölbung,nähern sich wieder etwas der Norm an. Sichere Hinweise für ein Übergreifen der Synostose auf andere Nähte wurden nicht gefunden. Im weiteren wurden digitale und konventionelle Röntgenaufnahmen von 33 Patienten mit Kraniostenosen verglichen. Untersucht wurde die Beurteilbarkeit hinsichtlich Schärfe und Kontrast. Der Zeitabstand zwischen konventioneller und digitaler Röntgenaufnahme lag im Mittel bei 24 Monaten. Die Vorteile des digitalen Röntgens hinsichtlich der Beurteilbarkeit konnten deutlich gezeigt werden. Somit ist das optimierte digitale Röntgensystem dem konventionellen vorzuziehen. N2 - Purpose: To characterize the spontaneous clinical course of isolated sagittal synostosis based on planar skull radiography. Materials and Methods: In this retrospective analysis we evaluated a total of 155 radiographs of 55 children 2 weeks to 9 years old. The sagittal, coronal and lambdoid sutures were evaluated on the basis of pairs of ap and lateral radiographs. The sutures were examined with respect to their boundary, activity, and conspicuity to be visualized (based on a 3-grade score system). Six selected points on the skull X-ray defined eight measured distances, three angles, and a width-length index. To document changes over time, the measurements were correlated to normal values. In addition, a correlation between suture activity and selected parameters was evaluated. Results: The sagittal suture could be continuously or partially depicted in more then half of all radiographs taken during the first year of life. The measured distances and angles were concordant with results from the literature. With increasing age, the width-length index deviated from standard values while other parameters approximated the norm. Conclusion: In the case of children younger than twelve months, the sagittal suture appears radiologically open in many cases despite clear-cut scaphocephaly. Definite signs of progressive plurisutural fusion were not found in this series. The dolichocephalic deformity remained unchanged while some signs of scaphocephalic appearance actually improved. Key words KW - Kraniostenose KW - Konservative Therapie KW - Radiologie KW - Vergleich konservative digitale Röntgentechnik KW - pathology KW - skull KW - radiography Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-24310 ER - TY - THES A1 - Feldner, Natascha Christina Maria T1 - Die interventionelle Therapie von Lebertumoren - Würzburger Ergebnisse und Verträglichkeit der transarteriellen Chemoembolisation (TACE) T1 - Interventional therapy of livertumours - A study from the university of Würzburg on tolerability of TACE N2 - Zusammenfassung Einleitung: Die Therapie der Lebertumore stellt nach wie vor eine Herausforderung für alle beteiligten Disziplinen dar. Die Universitätskliniken Würzburg verfügen über ein interdisziplinäres Therapiekonzept. Diese Studie aus der Abteilung für Röntgendiagnostik der Universität Würzburg ist ein Vergleich der eigenen Ergebnisse nach interventionellen Therapien von Lebertumoren, im Speziellen nach TACE, mit Daten der Literatur. Besonders berücksichtigt wurden die Auswirkungen auf die Lebensqualität und mögliche Komplikationen. Material und Methode: Von September 1994 bis April 2003 wurden die Lebertumore von 54 Patienten mit insgesamt 135 transarteriellen Chemoembolisationen (TACE) behandelt. Berücksichtigt wurden das Verhalten des Tumors, die Entwicklung des Karnofsky-Index, die Dauer des stationären Aufenthalts, die Kombination mit weiteren Therapieoptionen, die Überlebenszeit für die Monotherapie mit TACE und die Kombinationstherapie aus TACE und PEI / RFA, die Entwicklung ausgewählter Laborparameter, das Auftreten von Nebenwirkungen und Beschwerden nach TACE, die Ausprägung des Postembolisationssyndroms sowie aufgetretene Komplikationen und Embolisatverschleppungen. Ergebnisse: Die TACE hat sich unter Beachtung ihrer Kontraindikationen und der jeweiligen Situation des einzelnen Patienten als sichere und effektive Methode für die palliative Therapie von Lebertumoren erwiesen. Sie führt zu einer Verlängerung der Überlebenszeit, wobei sich die Kombination aus TACE und PEI / RFA der Monotherapie mit TACE überlegen darstellte. Auftretende Nebenwirkungen sind in der Regel vorübergehend, schwere Komplikationen und wesentliche Einschränkungen der Lebensqualität traten nur in Einzelfällen auf. Schlussfolgerung: Die Ergebnisse aus unserer Abteilung weisen eine gute Verträglichkeit der TACE für die Patienten nach und unterstreichen ihren Stellenwert in der Therapie primär inoperabler Lebertumore. N2 - Abstract Background and aims: The therapy of livertumours is still a challenge for all involved disciplines. The clinics of the university of Würzburg are using an interdisciplinary therapy concept. The following study from the department for x-ray diagnostics of the university of Würzburg is a comparison between our results of the interventional therapies of the livertumours especially using the TACE, with data from the literature. A special focus was made on the effects on the quality of life and possible complications. Materials and methods: From September 1994 to April 2003 54 patients with livertumours were treated with in all 135 transarterial chemoembolizations (TACE). Certain aspects were evaluated, such as the reaction of the tumours, the development of the Karnofsky-index, the duration of the stationary treatments, the combination with additional therapies, the survival rate with a single therapy with TACE alone and with a combination therapy consisting of TACE and PEI / RFA, the development of chosen laboratory parameters, the occurrence of side effects and complaints after the use of the TACE therapy, the development of the postembolisations syndromes as well as accruing complications and embolisations protractions. Results: The TACE has proven itself to be a safe and effective method for the palliative therapy of livertumours while considering the contraindications and the individual situations of the patients. The therapy leads a lengthening of the survival, whereas the combination of TACE and PEI / RFA has shown to be superior to the therapy consisting of TACE alone. Occurring side effects are usually only temporary, heavy complications and essential restrictions in the quality of life occurred only in isolated cases. Conclusion: The results form our department prove a good tolerability of the TACE for patients and underline its place value in the therapy of primarily inoperable livertumour. KW - Lebensqualität KW - interventionelle Therapie KW - Lebertumore KW - hepatozelluläres Karzinom (HCC) KW - transarterielle Chemomebolisation (TACE) KW - interventional therapy KW - livertumour KW - transarterial chemoembolization (TACE) KW - quality of life KW - hepatocellular carcinoma (HCC) Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-36504 ER - TY - JOUR A1 - Fabritius, Matthias Philipp A1 - Wölfer, Teresa A. A1 - Herzberg, Moriz A1 - Tiedt, Steffen A1 - Puhr-Westerheide, Daniel A1 - Grosu, Sergio A1 - Maurus, Stefan A1 - Geyer, Thomas A1 - Curta, Adrian A1 - Kellert, Lars A1 - Küpper, Clemens A1 - Liebig, Thomas A1 - Ricke, Jens A1 - Dimitriadis, Konstantinos A1 - Kunz, Wolfgang G. A1 - Zimmermann, Hanna A1 - Reidler, Paul T1 - Course of early neurologic symptom severity after endovascular treatment of anterior circulation large vessel occlusion stroke: association with baseline multiparametric CT imaging and clinical parameters JF - Diagnostics N2 - Background: Neurologic symptom severity and deterioration at 24 hours (h) predict long-term outcomes in patients with acute large vessel occlusion (LVO) stroke of the anterior circulation. We aimed to examine the association of baseline multiparametric CT imaging and clinical factors with the course of neurologic symptom severity in the first 24 h after endovascular treatment (EVT). Methods: Patients with LVO stroke of the anterior circulation were selected from a prospectively acquired consecutive cohort of patients who underwent multiparametric CT, including non-contrast CT, CT angiography and CT perfusion before EVT. The symptom severity was assessed on admission and after 24 h using the 42-point National Institutes of Health Stroke Scale (NIHSS). Clinical and imaging data were compared between patients with and without early neurological deterioration (END). END was defined as an increase in ≥4 points, and a significant clinical improvement as a decrease in ≥4 points, compared to NIHSS on admission. Multivariate regression analyses were used to determine independent associations of imaging and clinical parameters with NIHSS score increase or decrease in the first 24 h. Results: A total of 211 patients were included, of whom 38 (18.0%) had an END. END was significantly associated with occlusion of the internal carotid artery (odds ratio (OR), 4.25; 95% CI, 1.90–9.47) and the carotid T (OR, 6.34; 95% CI, 2.56–15.71), clot burden score (OR, 0.79; 95% CI, 0.68–0.92) and total ischemic volume (OR, 1.01; 95% CI, 1.00–1.01). In a comprehensive multivariate analysis model including periprocedural parameters and complications after EVT, carotid T occlusion remained independently associated with END, next to reperfusion status and intracranial hemorrhage. Favorable reperfusion status and small ischemic core volume were associated with clinical improvement after 24 h. Conclusions: The use of imaging parameters as a surrogate for early NIHSS progression in an acute LVO stroke after EVT reached limited performance with only carotid T occlusion as an independent predictor of END. Reperfusion status and early complications in terms of intracranial hemorrhage are critical factors that influence patient outcome in the acute stroke phase after EVT. KW - stroke KW - large vessel occlusion KW - multiparametric CT KW - CT perfusion KW - CT angiography KW - NIHSS KW - EVT Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-242681 SN - 2075-4418 VL - 11 IS - 7 ER - TY - JOUR A1 - Ewald, Andrea A1 - Fuchs, Andreas A1 - Boegelein, Lasse A1 - Grunz, Jan-Peter A1 - Kneist, Karl A1 - Gbureck, Uwe A1 - Hoelscher-Doht, Stefanie T1 - Degradation and bone-contact biocompatibility of two drillable magnesium phosphate bone cements in an in vivo rabbit bone defect model JF - Materials N2 - The use of bone-cement-enforced osteosynthesis is a growing topic in trauma surgery. In this context, drillability is a desirable feature for cements that can improve fracture stability, which most of the available cement systems lack. Therefore, in this study, we evaluated a resorbable and drillable magnesium-phosphate (MgP)-based cement paste considering degradation behavior and biocompatibility in vivo. Two different magnesium-phosphate-based cement (MPC) pastes with different amounts of phytic acid (IP 6) as setting retarder (MPC 22.5 and MPC 25) were implanted in an orthotopic defect model of the lateral femoral condyle of New Zealand white rabbits for 6 weeks. After explantation, their resorption behavior and material characteristics were evaluated by means of X-ray diffraction (XRD), porosimetry measurement, histological staining, peripheral quantitative computed tomography (pQCT), cone-beam computed tomography (CBCT) and biomechanical load-to-failure tests. Both cement pastes displayed comparable results in mechanical strength and resorption kinetics. Bone-contact biocompatibility was excellent without any signs of inflammation. Initial resorption and bone remodeling could be observed. MPC pastes with IP 6 as setting retardant have the potential to be a valuable alternative in distinct fracture patterns. Drillability, promising resorption potential and high mechanical strength confirm their suitability for use in clinical routine. KW - magnesium phosphate cement KW - phytic acid KW - drillability KW - bone replacement material Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-362824 SN - 1996-1944 VL - 16 IS - 13 ER - TY - THES A1 - Evangelista, Laura T1 - Innovative Anwendungen der diffusionsgewichteten MRT in der pädiatrischen muskuloskelettalen Bildgebung T1 - Innovative applications of diffusion-weighted MRI in pediatric musculoskeletal imaging analisys N2 - Die vorliegende Arbeit untesucht die Darstellung tumoröser und entzündlicher muskuloskelettaler Läsionen mit der diffusionsgewichteten MRT-Bildgebung bei Kindern und Jugendlichen. Es sollten die Machbarkeit und die Zuverlässigkeit der Methode in der klinischen Routinebildgebung überprüft werden. Zusätzlich untersuchten wir den Einsatz von ADC-Werten zur Differenzierung von malignen und benignen Tumoren sowie bei inflammatorischen Knochen- und Weichteilbefunden. Wie die klassische MRT, ist die diffusionsgewichtete Bildgebung nicht-invasiv: da der Bildkontrast allein mittels magnetischer Feldgradienten erzielt wird, erfordert sie weder eine Injektion von Kontrastmitteln, noch den Einsatz von ionisierender Strahlung. Sie garantiert eine schnelle Aquisitionstechink um Artefakte zu begrenzen und die Untersuchungen kindergerechter zu gestalten. Die von uns erfassten Daten wurden in zwei unterschiedlichen Studien aufgeteilt. Die Erste Studie erfasst Ergebnisse bzgl. der Detektion und Dignitätsabschätzung kinderlicher muskuloskelettaler Tumoren mittels diffusionsgewichteten MRT Bilder. Das zweite Forschungsprojekt, befasst sich mit dem erstmaligen Einsatz der diffusionsgewichteten MRT zur Identifikation und Differenzierung von Knochenmarködem, Weichteilödem und Synovitis bei pädiatrischen Patienten. N2 - This study investigates the presentation of tumorous and inflammatory musculoskeletal lesions by diffusion-weighted MRI imaging in children and adolescents. The feasibility and reliability of the method should be tested in clinical routine imaging. In addition, we investigated the use of ADC values ​​for the differentiation of malignant and benign tumors as well as for inflammatory bone and soft tissue findings. Like the classical MRI, diffusion-weighted imaging is non-invasive: since the image contrast is achieved solely by means of magnetic field gradients, it does not require either the injection of contrast agents or the use of ionizing radiations. This technique allows a quick aquisition to limit artefacts and to shape the investigations in a more child-friendly way. The data we collected were divided into two different studies. The first study records results concerning the detection and dignity-assessment of childhood musculoskeletal tumors using diffusion-weighted MRI images. The second research project deals with the initial use of diffusion-weighted MRI for the identification and differentiation of bone marrow edema, soft tissue edema and synovitis in Pediatric patients. KW - Diffusionsgewichtete Magnetresonanztomographie KW - Diffusions-MRT KW - DW-MRI KW - Pädiatrie KW - muskuloskelettalen Bildgebung KW - pädiatrischen Tumoren Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-145065 ER - TY - JOUR A1 - Elsner, Clara A1 - Kunz, Andreas Steven A1 - Wagner, Nicole A1 - Huflage, Henner A1 - Hübner, Stefan A1 - Luetkens, Karsten Sebastian A1 - Bley, Thorsten Alexander A1 - Schmitt, Rainer A1 - Ergün, Süleyman A1 - Grunz, Jan-Peter T1 - MRI-based evaluation of the flexor digitorum superficialis anatomy: investigating the prevalence and morphometry of the “chiasma antebrachii” JF - Diagnostics N2 - Recent dissection studies resulted in the introduction of the term “chiasma antebrachii”, which represents an intersection of the flexor digitorum superficialis (FDS) tendons for digits 2 and 3 in the distal third of the forearm. This retrospective investigation aimed to provide an MRI-based morphologic analysis of the chiasma antebrachii. In 89 patients (41 women, 39.3 ± 21.3 years), MRI examinations of the forearm (2010–2021) were reviewed by two radiologists, who evaluated all studies for the presence and length of the chiasma as well as its distance from the distal radioulnar and elbow joint. The chiasma antebrachii was identified in the distal third of the forearm in 88 patients (98.9%), while one intersection was located more proximally in the middle part. The chiasma had a median length of 28 mm (interquartile range: 24–35 mm). Its distances to the distal radioulnar and elbow joint were 16 mm (8–25 mm) and 215 mm (187–227 mm), respectively. T1-weighted post-contrast sequences were found to be superior to T2- or proton-density-weighted sequences in 71 cases (79.8%). To conclude, the chiasma antebrachii is part of the standard FDS anatomy. Knowledge of its morphology is important, e.g., in targeted injections of therapeutics or reconstructive surgery. KW - flexor digitorum superficialis KW - flexor tendon KW - chiasma antebrachii KW - magnetic resonance imaging Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-362631 SN - 2075-4418 VL - 13 IS - 14 ER - TY - JOUR A1 - Duhr, Carolin D. A1 - Kenn, Werner A1 - Kickuth, Ralph A1 - Kerscher, Alexander G. A1 - Germer, Christoph-Thomas A1 - Hahn, Dietbert A1 - Pelz, Joerg O. W. T1 - Optimizing of preoperative computed tomography for diagnosis in patients with peritoneal carcinomatosis JF - World Journal of Surgical Oncology N2 - Background and Objective This study evaluates whether Computer Tomography is an effective procedure for preoperative staging of patients with Peritoneal Carcinomatosis. Method A sample of 37 patients was analyzed with contrast enhanced abdominal Computer Tomography, followed by surgical staging. All Computer Tomography scans were evaluated 3 times by 2 radiologists with one radiologist reviewing 2 times. The efficacy of Computer Tomography was evaluated using the Spearman correlation coefficient. Correlations were analyzed by abdominopelvic region to assess results of the Peritoneal Carcinomatosis Index (PCI) aggregating the 13 regions. Surgical findings were compared to radiological findings. Results Results indicate high correlations between the surgical and radiological Peritoneal Carcinomatosis Indices. Analyses of the intra-class correlation between the first and second reading of one radiologist suggest high intra-observer reliability. Correlations by abdominopelvic region show higher values in the upper and middle regions and relatively lower values in the lower regions and the small bowel (correlation coefficients range between 0.418 and 0.726, p < 0.010; sensitivities range between 50% and 96%; and specificities range between 62% and 100%). Conclusion Computer Tomography represents an effective procedure in the preoperative staging of patients with PC. However, results by abdominopelvic region show lower correlation, therefore suggest lower efficacy. These results are supported by analyses of sensitivity and accuracy by lesion size. This suggests that Computer Tomography is an effective procedure for pre-operative staging but less for determining a tumor's accurate extent. KW - Carcinomatosis KW - diagnosis KW - PCI Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-138024 VL - 9 IS - 171 ER - TY - THES A1 - Dragolea, Darius T1 - Ergebnisqualität von klinischen und Vorsorgemammographien im Vergleich zu internationalen Leitlinien für Brustkrebsscreening T1 - The quality of the results of diagnostic and screening mammographic examinations in comparison with international breast cancer screening guidelines N2 - Durch den mehrfachen Führungswechsel in der Radiologischen Abteilung der Frauenklinik der Universität Würzburg seit 1995, ergab sich die Frage, ob die verantwortlichen Radiologen sich in der Mammographiebeurteilung unterscheiden. Ausgehend von 8033 Mammographien von asymptomatischen- und Patientinnen mit einem klinischen Befund, wurde die Sensitivität, Spezifität, die Biopsierate, die Tumorentdeckung- und Recallrate für die einzelnen Untersucher ermittelt. Die wesentlichen Ergebnisse dieser Arbeit sind: 1. Die Sensitivität liegt bei durchschnittlich 97,14%, die Spezifität 98,62%. Die Tumorentdeckungsrate liegt zwischen 6,59‰ und 8,99‰, die Biopsierate beträgt 1,34% und die Recallrate 3,79%. 2. Für alle Behandler liegen diese Werte innerhalb der vom American College of Radiology und den European Guidelines for Quality Assurance in Mammography Screening vorgegebenen Richtlinien. 3. Es gibt keine signifikanten Unterschiede in der Mammographiebefundung durch die verschiedenen Untersucher. 4. Durch die Einführung der standardisierten Klassifikation der Befunde wird in Zukunft eine Qualitätssicherung der Mammographieuntersuchungen und eine Kontrolle der Ergebnisse gewährleistet. N2 - The frequent changes of management in the Radiological Department of the Gynaecological Clinic of the University of Würzburg since 1995 gave rise to the question of whether the radiologists responsible differed in their assessments of mammographical examinations. The sensitivity, specifity, biopsy rate, cancer detection rate and recall rate were calculated for each inidividual examining physician on the basis of 8033 mammographies of asymptomatic patients and patients with clinical symptoms. The primary results of this study were as follows: 5. The average sensitivity came to 97.14% and the average specifity came to 98.62%. The cancer detection rate was between 6.59‰ and 8.99‰, the biopsy rate was 1.34% and the recall rate was 3.79%. 6. These values fell within the guidelines specified by the American College of Radiology and the European Guidelines for Quality Assurance in Mammography Screening for all examining physicians. 7. There were no significant differences between the individual examining physicians with respect to their mammographical assessments. 8. The introduction of the standardised classification of the assessments will in future guarantee quality assurance in mammographical examinations and ensure that the results can be monitored. KW - Mammographie KW - Sensitivität KW - Spezifität KW - Tumorentdeckungsrate KW - mammography KW - sensitivity KW - specifity KW - cancer detection rate Y1 - 2005 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-12306 ER - TY - JOUR A1 - Dorn, Franziska A1 - Herzberg, Moriz T1 - Response to Letter to the Editor “Keeping Late Thrombectomy Imaging Protocols Simple to Avoid Analysis Paralysis” JF - Clinical Neuroradiology KW - neuroradiology KW - neurosurgery KW - neurology Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307023 SN - 1869-1439 SN - 1869-1447 VL - 31 IS - 3 ER - TY - THES A1 - Dietrich, Philipp T1 - Traveling Wave Magnetic Particle Imaging: Visuelle Stenosequantifizierung und Perkutane Transluminale Angioplastie im Gefäßmodell T1 - Traveling Wave Magnetic Particle Imaging: visual stenosis quantification and percutaneous transluminal angioplasty in a phantom model N2 - Magnetic Particle Imaging (MPI) ist ein innovatives tomographisches Bildgebungs­verfahren, mit dem Tracerpartikel äußerst sensitiv und schnell mehrdimensional abgebildet werden können. Die Methode basiert auf der nichtlinearen Magnetisierungs­antwort superparamagnetischer Eisenoxidnanopartikel (SPION) in einem Messpunkt, welcher ein Messvolumen rastert. In vorliegender Arbeit wurde das sog. Traveling Wave MPI (TWMPI) Verfahren eingesetzt, wodurch im Vergleich zu konventionellen MPI-Scannern ein größeres Field of View (FOV) und eine geringere Latenz bis zur Bildanzeige erreicht werden konnte. TWMPI weist einige für medizinische Zwecke vielversprechende Eigenschaften auf: Es liefert zwei- und dreidimensionale Bildrekonstruktionen in Echtzeit mit hoher zeitlicher und räumlicher Auflösung. Dabei ist die Bildgebung von Grund auf hintergrundfrei und erfordert keinerlei ionisierende Strahlung. Zudem ist die Technik äußerst sensitiv und kann SPION-Tracer noch in mikromolaren Konzentrationen detektieren. Ziel dieser Arbeit war es daher zu untersuchen, inwiefern es mittels TWMPI möglich ist, künstliche Stenosen im Gefäßmodell visuell in Echtzeit darzustellen und quantitativ zu beurteilen sowie überdies eine perkutane transluminale Angioplastie (PTA) im Gefäßmodell unter TWMPI-Echtzeit-Bildgebung durchzuführen. Alle Experimente wurden in einem speziell angefertigten TWMPI-Scanner durchgeführt (JMU Würzburg, Experimentelle Physik V (Biophysik), FOV: 65 x 29 x 29 mm³, Auflösung: ca. 1.5 - 2 mm). Die Lumen-Darstellungen erfolgten mittels des SPION-Tracers Ferucarbotran in einer Verdünnung von 1 : 50 (entspr. 10 mmol [Fe]/l). Das PTA-Instrumentarium wurde mit eigens hergestelltem ferucarbotran­haltigem Lack (100 mmol [Fe]/l) markiert. Für die verschiedenen Teilexperimente wurden den jeweiligen speziellen Anforderungen entsprechend mehrere Gefäßmodelle handgefertigt. Für die visuelle Stenosequantifizierung wurden fünf starre Stenosephantome unterschiedlicher Stenosierung (0%, 25%, 50%, 75%, 100%) aus Polyoxymethylen her­gestellt (l: 40 mm, ID: 8 mm). Die Gefäßmodelle wurden mehrfach zentral im FOV platz­iert und das stenosierte Lumen mittels sog. Slice-Scanning Modus (SSM, Einzel­aufnahme inkl. 10 Mittelungen: 200 ms, Bildfrequenz: 5 Bilder pro Sekunde, Latenz: ca. 100 ms) als zweidimensionale Quasi-Projektionen abgebildet. Diese Aufnahmen (n = 80, 16 je Phantom) wurden mit einer ein­heitlichen Grauskalierung versehen und anschließend entsprechend den NASCET-Kriterien visuell ausgewertet. Alle achtzig Aufnahmen waren unabhängig vom Stenosegrad aufgrund einheitlicher Fensterung sowie konstanter Scannerparameter untereinander gut vergleichbar. Niedrig­gradige Stenosen konnten insgesamt genauer abgebildet werden als höhergradige, was sich neben der subjektiven Bildqualität auch in geringeren Standardabweichungen zeigte (0%: 3.70 % ± 2.71, 25%: 18.64 % ± 1.84, 50%: 52.82 % ± 3.66, 75%: 77.84 % ± 14.77, 100%: 100 % ± 0). Mit zunehmendem Stenosegrad kam es vermehrt zu geometrischen Ver­zerrungen im Zentrum, sodass bei den 75%-Stenosen eine breitere Streuung der Messwerte mit einer höheren Standardabweichung von 14.77% einherging. Leichte, randständige Artefakte konnten bei allen Datensätzen beobachtet werden. Für die PTA wurden drei interaktive Gefäßmodelle aus Polyvinylchlorid (l: 100 mm, ID: 8 mm) mit zu- und abführendem Schlauchsystem entwickelt, welche mittels Kabelband von außen hochgradig eingeengt werden konnten. Analog zu einer konventionellen PTA mittels röntgenbasierter digitaler Subtraktionsangiographie (DSA), wurden alle erforder­lichen Arbeitsschritte (Gefäßdarstellung, Drahtpassage, Ballonplatzierung, Angioplastie, Erfolgskontrolle) unter (TW)MPI-Echtzeit-Bildgebung (Framerate: 2 - 4 FPS, Latenz: ca. 100 ms) abgebildet bzw. durchgeführt. Im Rahmen der PTA war eine Echtzeit-Visualisierung der Stenose im Gefäßmodell durch Tracer-Bolusgabe sowie die Führung des markierten Instrumentariums zum Zielort möglich. Die Markierung der Instrumente hielt der Beanspruchung während der Prozedur stand und ermöglichte eine genaue Platzierung des Ballonkatheters. Die Stenose konnte mittels Angioplastie-Ballons unter Echtzeit-Darstellung gesprengt werden und der Interventionserfolg im Anschluss durch erneute Visualisierung des Lumens validiert werden. Insgesamt zeigt sich MPI somit als adäquate Bildgebungstechnik für die beiden in der Fragestellung bzw. Zielsetzung definierten experimentellen Anwendungen. Stenosen im Gefäßmodell konnten erfolgreich in Echtzeit visualisiert und bildmorphologisch nach NASCET-Kriterien quantifiziert werden. Ebenso war eine PTA im Gefäßmodell unter TWMPI-Echtzeit-Bildgebung machbar. Diese Ergebnisse unter­streichen das grundlegende Potenzial von MPI für medizinische Zwecke. Um zu den bereits etablierten Bildgebungsmethoden aufzuschließen, ist jedoch weitere Forschung im Bereich der Scanner-Hard- und -Software sowie bezüglich SPION-Tracern nötig. N2 - Magnetic Particle Imaging (MPI) is an innovative tomographic imaging method with which tracer particles can be depicted multidimensionally quickly and extremely sensitively. The method is based on the nonlinear magnetization response of superparamagnetic iron oxide nanoparticles (SPION) in a measuring point that runs through a measurement volume. In the present work, the so-called Traveling Wave MPI (TWMPI) method was used, whereby a larger Field of View (FOV) and a lower latency from measurement to image display could be achieved compared to conventional MPI scanners. TWMPI has some promising properties for medical purposes: it delivers two- and three-dimensional image reconstructions in real time with high temporal and spatial resolution. The imaging is background-free by default and does not require any ionizing radiation. In addition, the technology is extremely sensitive and can detect SPION tracers in micromolar concentrations. The aim of this work was therefore to investigate to what extent it is possible to use TWMPI to graphically visualize and quantitatively assess artificial stenoses in a phantom model in real time and furthermore to perform a percutaneous transluminal angioplasty (PTA) in a phantom model under TWMPI real-time imaging. All experiments were carried out in a specially manufactured TWMPI scanner (JMU Würzburg, Experimental Physics V (Biophysics), FOV: 65 x 29 x 29 mm³, resolution: approx. 1.5 - 2 mm). Lumen visualization was achieved by use of the SPION tracer Ferucarbotran in a dilution of 1 : 50 (corresponding to 10 mmol [Fe] / l). The PTA instruments were marked with specially produced ferucarbotran-containing lacquer (100 mmol [Fe]/l). For the different sub-experiments, several vessel phantoms were custom-made according to the respective specific requirements. For visual stenosis quantification, five rigid stenosis phantoms of different grade of stenosis (0%, 25%, 50%, 75%, 100%) were built from polyoxymethylene (l: 40 mm, ID: 8 mm). The vessel phantoms were placed centrally in the FOV several times and the stenotic lumen was depicted as two-dimensional quasi-projections using a so-called slice scanning mode (SSM, single recording incl. averaging 10‑fold: 200 ms, frame rate: 5 frames per second, latency: approx. 100 ms). A uniform gray scaling was applied to these images (n = 80, 16 per phantom) before they were visually evaluated according to the NASCET criteria. Due to the uniform gray scaling, display settings and constant scanner parameters, all eighty images were well comparable with each other, regardless of the degree of stenosis. Overall, low-grade stenoses could be depicted more accurately than higher-grade ones, which, in addition to the subjective image quality, was also reflected in lower standard deviations (0%: 3.70 % ± 2.71, 25%: 18.64 % ± 1.84, 50%: 52.82 % ± 3.66, 75%: 77.84 % ± 14.77, 100%: 100 % ± 0). With increasing­ degree of stenosis, geometric distortions in the center increased, so that within the 75% stenoses a wider spread of the measured values led to a higher standard deviation of 14.77%. Faint, marginal artifacts could be observed over all data sets. For PTA, three interactive vessel phantoms made of polyvinyl chloride (l: 100 mm, ID: 8 mm) were developed with additional tubing to and from the phantom. These vessel phantoms could be highly constricted from the outside by use of cable ties. Analogous to a conventional PTA using X-ray-based digital subtraction angiography (DSA), all necessary steps (vascular visualization, wire passage, balloon placement, angioplasty, control imaging) were depicted by resp. carried out under (TW)MPI real-time imaging (frame rate: 2 – 4 FPS, latency: approx. 100 ms). During the PTA, real-time visualization of the stenosis in the vascular phantom by tracer bolus administration as well as guidance of the marked instruments to the destination was possible. The marking of the instruments withstood the stress during the procedure and allowed an accurate placement of the balloon catheter. The stenosis could be dilated with an angioplasty balloon under real-time imaging and the intervention success could then be validated by re-visualization of the lumen. Overall, MPI thus proves to be an adequate imaging technique in regard of the two experimental applications defined in the questions and aims of this study. Stenoses in a vascular phantom could be successfully visualized in real time and quantified visually according to NASCET criteria. Furthermore, a PTA in a vascular phantom guided by TWMPI real-time imaging was feasible. These findings underscore the fundamental potential of MPI for medical purposes. In order to catch up with the already established imaging methods, however, further research is needed in the field of scanner hard- and software as well as regarding SPION tracers. KW - Medizinische Radiologie KW - Magnetpartikelbildgebung KW - Interventionsradiologie KW - Experimentelle Bildgebung KW - Magnetic Particle Imaging KW - Traveling Wave Magnetic Particle Imaging KW - Interventionelle Radiologie KW - MPI KW - experimental imaging KW - magnetic particle imaging KW - traveling wave magnetic particle imaging KW - interventional radiology KW - Transluminale Angioplastie KW - MPI Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-352517 ER - TY - JOUR A1 - Diessner, Joachim A1 - Anders, Laura A1 - Herbert, Saskia A1 - Kiesel, Matthias A1 - Bley, Thorsten A1 - Schlaiss, Tanja A1 - Sauer, Stephanie A1 - Wöckel, Achim A1 - Bartmann, Catharina T1 - Evaluation of different imaging modalities for axillary lymph node staging in breast cancer patients to provide a personalized and optimized therapy algorithm JF - Journal of Cancer Research and Clinical Oncology N2 - Purpose The reliable detection of tumor-infiltrated axillary lymph nodes for breast cancer [BC] patients plays a decisive role in further therapy. We aimed to find out whether cross-sectional imaging techniques could improve sensitivity for pretherapeutic axillary staging in nodal-positive BC patients compared to conventional imaging such as mammography and sonography. Methods Data for breast cancer patients with tumor-infiltrated axillary lymph nodes having received surgery between 2014 and 2020 were included in this study. All examinations (sonography, mammography, computed tomography [CT] and magnetic resonance imaging [MRI]) were interpreted by board-certified specialists in radiology. The sensitivity of different imaging modalities was calculated, and binary logistic regression analyses were performed to detect variables influencing the detection of positive lymph nodes. Results All included 382 breast cancer patients had received conventional imaging, while 52.61% of the patients had received cross-sectional imaging. The sensitivity of the combination of all imaging modalities was 68.89%. The combination of MRI and CT showed 63.83% and the combination of sonography and mammography showed 36.11% sensitivity. Conclusion We could demonstrate that cross-sectional imaging can improve the sensitivity of the detection of tumor-infiltrated axillary lymph nodes in breast cancer patients. Only the safe detection of these lymph nodes at the time of diagnosis enables the evaluation of the response to neoadjuvant therapy, thereby allowing access to prognosis and improving new post-neoadjuvant therapies. KW - breast cancer imaging KW - positive nodal status KW - cross-sectional imaging KW - conventional imaging KW - post-neoadjuvant therapies KW - neoadjuvant therapies Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324047 VL - 149 IS - 7 ER - TY - JOUR A1 - Detomas, Mario A1 - Altieri, Barbara A1 - Schlötelburg, Wiebke A1 - Appenzeller, Silke A1 - Schlaffer, Sven A1 - Coras, Roland A1 - Schirbel, Andreas A1 - Wild, Vanessa A1 - Kroiss, Matthias A1 - Sbiera, Silviu A1 - Fassnacht, Martin A1 - Deutschbein, Timo T1 - Case Report: Consecutive Adrenal Cushing’s Syndrome and Cushing’s Disease in a Patient With Somatic CTNNB1, USP8, and NR3C1 Mutations JF - Frontiers in Endocrinology N2 - The occurrence of different subtypes of endogenous Cushing’s syndrome (CS) in single individuals is extremely rare. We here present the case of a female patient who was successfully cured from adrenal CS 4 years before being diagnosed with Cushing’s disease (CD). The patient was diagnosed at the age of 50 with ACTH-independent CS and a left-sided adrenal adenoma, in January 2015. After adrenalectomy and histopathological confirmation of a cortisol-producing adrenocortical adenoma, biochemical hypercortisolism and clinical symptoms significantly improved. However, starting from 2018, the patient again developed signs and symptoms of recurrent CS. Subsequent biochemical and radiological workup suggested the presence of ACTH-dependent CS along with a pituitary microadenoma. The patient underwent successful transsphenoidal adenomectomy, and both postoperative adrenal insufficiency and histopathological workup confirmed the diagnosis of CD. Exome sequencing excluded a causative germline mutation but showed somatic mutations of the β-catenin protein gene (CTNNB1) in the adrenal adenoma, and of both the ubiquitin specific peptidase 8 (USP8) and the glucocorticoid receptor (NR3C1) genes in the pituitary adenoma. In conclusion, our case illustrates that both ACTH-independent and ACTH-dependent CS may develop in a single individual even without evidence for a common genetic background. KW - Cushing’s syndrome KW - Cushing’s disease KW - hypercortisolism KW - glucocorticoid excess KW - USP8 KW - CTNNB1 KW - NR3C1 Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244596 SN - 1664-2392 VL - 12 ER - TY - JOUR A1 - Conrads, Nora A1 - Grunz, Jan-Peter A1 - Huflage, Henner A1 - Luetkens, Karsten Sebastian A1 - Feldle, Philipp A1 - Grunz, Katharina A1 - Köhler, Stefan A1 - Westermaier, Thomas T1 - Accuracy of pedicle screw placement using neuronavigation based on intraoperative 3D rotational fluoroscopy in the thoracic and lumbar spine JF - Archives of Orthopaedic and Trauma Surgery N2 - Introduction In spinal surgery, precise instrumentation is essential. This study aims to evaluate the accuracy of navigated, O-arm-controlled screw positioning in thoracic and lumbar spine instabilities. Materials and methods Posterior instrumentation procedures between 2010 and 2015 were retrospectively analyzed. Pedicle screws were placed using 3D rotational fluoroscopy and neuronavigation. Accuracy of screw placement was assessed using a 6-grade scoring system. In addition, screw length was analyzed in relation to the vertebral body diameter. Intra- and postoperative revision rates were recorded. Results Thoracic and lumbar spine surgery was performed in 285 patients. Of 1704 pedicle screws, 1621 (95.1%) showed excellent positioning in 3D rotational fluoroscopy imaging. The lateral rim of either pedicle or vertebral body was protruded in 25 (1.5%) and 28 screws (1.6%), while the midline of the vertebral body was crossed in 8 screws (0.5%). Furthermore, 11 screws each (0.6%) fulfilled the criteria of full lateral and medial displacement. The median relative screw length was 92.6%. Intraoperative revision resulted in excellent positioning in 58 of 71 screws. Follow-up surgery due to missed primary malposition had to be performed for two screws in the same patient. Postsurgical symptom relief was reported in 82.1% of patients, whereas neurological deterioration occurred in 8.9% of cases with neurological follow-up. Conclusions Combination of neuronavigation and 3D rotational fluoroscopy control ensures excellent accuracy in pedicle screw positioning. As misplaced screws can be detected reliably and revised intraoperatively, repeated surgery for screw malposition is rarely required. KW - pedicle screws KW - vertebral pedicles KW - fluoroscopy KW - neuronavigation KW - spine Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324966 VL - 143 IS - 6 ER - TY - THES A1 - Cao, Victoria Xinghui T1 - Stichkanalembolisation nach perkutaner transhepatischer Cholangiodrainage mittels Gelatineschwamm: Eine retrospektive Analyse T1 - Catheter tract embolization after percutaneous biliary drainage using gelatin sponge: a retrospective analysis N2 - Durch die Anlage einer perkutanen transhepatischen Cholangiodrainage (PTCD), im Rahmen benigner und maligner biliärer Obstruktionen, wird eine Kommunikation zwischen Hautoberfläche, Peritoneum und dem biliären System geschaffen. Insbesondere nach Entfernung der PTCD besteht das Risiko einer Galleleckage, einer Blutung, einer biliokutanen Fistel oder einer lokalen Peritonitis, mit durchaus schwerwiegenden Konsequenzen. Die Embolisation dieses Stichkanals nach Entfernung der Drainage mittels Gelatineschwamm (Gelfoam) stellt eine einfache und effektive Lösung dar diese Komplikationen zu reduzieren und zu verhindern. Ziel dieser Studie war es, die Effektivität der Stichkanalembolisation mittels Gelatineschwamm nach PTCD retrospektiv zu evaluieren. N2 - Applying percutaneous biliary drainage (PTBD) in the context of benign and malignant biliary obstructions, communication between the skin surface, peritoneum and the biliary system is created. Particularly after removal of the PTBD, there is a risk of bile leakage, bleeding, a bilio-cutaneous fistula or local peritonitis, with serious consequences. Transhepatic catheter tract embolization after removal of the drainage using gelatin sponge (Gelfoam) is a simple and effective method to reduce and prevent these complications. The aim of this study was to retrospectively evaluate the feasibility and safety of tract embolization after PTBD using gelatin sponge. KW - Embolisation KW - Stichkanalembolisation KW - Perkutane transhepatische Cholangiodrainage KW - Interventionelle Radiologie KW - Galle KW - Gelatineschwamm KW - tract embolization KW - percutaneous biliary drainage KW - Interventional radiology KW - Biliary KW - gelatin sponge Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-210855 ER - TY - THES A1 - Bürckstümmer, Ruth T1 - Quantitative 31P-MR-spektroskopische Untersuchung globaler Herzerkrankungen unterschiedlicher Genese - Verlaufsbeobachtung nach Aortenklappenersatz und unter Therapie bei Dilatativer Kardiomyopathie T1 - Quantitative 31P-NMR Spectroscopy in Global Heart Diseases of different genesis - Observations after Aortic Valve Replacement and during Therapy in Dilated Cardiomyopathy N2 - Die Arbeit zeigt bei verschiedenen Patientengruppen, dass mit Hilfe der quantitativen 31P-MR-Spektroskopie der Energiemetabolismus des Myokards beurteilt werden kann. Mit der gewählten Methode SLOOP ist nun auch eine Bestimmung der absoluten Konzentration der energiereichen Phosphate PCr und ATP möglich; im Gegensatz dazu wurde bisher nur das Verhältnis von PCr/ATP bestimmt. Die Beobachtungen bei Patienten mit Aortenklappenfehlern zeigten vor und nach Aortenklappenersatz Veränderungen, ebenso wurden bei Patienten mit Dilatativer Kardiomyopathie nach Einsatz von ß-Blockern bzw. nach Beginn regelmäßiger körperlicher Aktivität Verbessserungen des Energiestoffwechsels beobachet. N2 - The Study shows in different patient groups, that the high energy metabolism of myocardial tissue can be judged by 31P-NMR spectroscopy. With the chosen method SLOOP it is possible to do a quantitative determination of the high energy phosphates PCrand ATP unlike determining the ratio of PCr/ATP. The observations in patients with aortic valve diseases showed changes before and after valve replacement, in patients with dilated cardiomyopathy improvements of the energy metabolism could be observed as well after beginning of a ß-blocker therapy and after exercise. KW - Quantitative 31P-MR- Spektroskopie KW - Herzerkrankung KW - Aortenklappenersatz KW - DCM KW - 31P-MR-Spectroscopy KW - Heartdisease KW - Aortic Valve Replacement KW - DCM Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-8976 ER - TY - THES A1 - Böck, Lena T1 - Evaluation der präoperativen Ausdehnungsbestimmung ductaler Carcinomata in situ mittels hochauflösender 3-Tesla MR-Mammographie T1 - Evaluation of the Extension of ductal Carcinoma in situ with high resolution 3-Tesla MR mammography N2 - Zusammenfassend lässt sich sagen, dass auch in dieser Studie die MRT bewiesen hat, dass sie eine Diagnostik ist, die aufgrund ihrer vielen Vorteile (röntgenstrahlenfrei, schmerzfrei, hochauflösende Diagnostik) der konventionellen Mammographie überlegen ist. Im Vergleich mit anderen diagnostischen Möglichkeiten, weist die MRT die höchsten Sensitivitäten auf. Viele falsch positive Befunde könnten so vermieden werden und unnötige Biopsien umgangen werden. Die MRT zeigte in dieser Studie eine Sensitivität von 78%, für reine DCIS 76%. Die in der präoperativen MR-Diagnostik gemessenen Größen korrelierten statistisch signifikant mit der histologisch bestimmten Größe für alle Gruppen (reines DCIS, begleitendes DCIS, mikroinvasives DCIS) zusammen genommen (c=0,378; p<0,01) sowie für reine DCIS (c=0,403; p<0,05). Desweiteren korrelierten die Größen statistisch signifikant für high-grade DCIS (c=0,493; p<0,05) und für Nekrosen positive DCIS (c=0,556; p<0,01). Hier ließen sich die Tumorgrößen verlässlich vorhersagen. In der Auswertung der Signalintensitäts-Zeit-Kurven zeigten sich signifikante Unterschiede zwischen den Gruppen hinsichtlich der initialen (p<0,05) und postinitialen Phase (p<0,01). So lässt sich anhand der KM-Kinetik eine Aussage über die Malignität treffen. Ein reines DCIS zeigte typischerweise eine initiale Phase mit einem KM-Anstieg von 50-100% oder >100%, gefolgt von einer Plateau-Phase. Ein invasives Carcinom begleitendes DCIS zeichnete sich durch einen raschen Anstieg >100% gefolgt von einem „wash-out“ und einem inhomogenen, unbegrenzten Anreicherungsverhalten aus. Mikrovinvasive DCIS zeigten ähnlich den reinen DCIS einen initialen Anstieg von 50-100% sowie eine folgende Plateau-Phase. Keinen statistisch signifikanten Einfluss hatte die präoperative Größenbestimmung auf das operativen Verfahren (BET vs. Ablatio). Trotz der präoperativen MRT waren zu 29,6 % Nachresektionen - davon ca. die Hälfte (14,1%) als sekundäre Ablatio - nötig. Mit der MRT ließen sich grundsätzlich verlässliche präoperative Vorhersagen hinsichtlich Größe und Malignität treffen. Signalintensitäts-Zeit-Kurven und höhere Feldstärken, wie die 3T-MRT, könnten sehr hilfreich sein und die Sensitivität und Spezifität verbessern. Warum trotz allem noch so viele Nachresektionen nötig sind, gilt es in folgenden Studien zu untersuchen. N2 - Evaluation of the Extension of ductal Carcinoma in situ with high resolution 3-Tesla MR mammography KW - DCIS KW - MRT KW - duktal KW - Tesla KW - evaluation Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-169153 ER - TY - THES A1 - Bärwolff, Jennifer T1 - Prognostische Marker im MRT bei diffus intrinsischen Ponsgliomen im Kindesalter T1 - Diffuse intrinsic brainstem glioma in children – prognostic marker on MRI N2 - Das DIPG ist eine für die Kindheit recht spezifische Neoplasie und geht aufgrund seiner Lage im Hirnstamm mit diffusen Ausbreitungsmuster, sowie fehlendem Therapieansprechen mit einer sehr schlechten Prognose einher. 90% der betroffenen Kinder versterben innerhalb der ersten beiden Jahre nach Diagnosestellung. Ziel dieser Arbeit war es herauszufinden ob es bildgebende oder epidemiologische Merkmale gibt, die einen Einfluss auf die Überlebenszeiten zeigen und somit als prognostische Marker genutzt werden können. Die Daten der 253 Studienteilnehmer mit neudiagnostizierten DIPG stammen aus der HIT-HGG-2007-Studie, sowie den 4 Vorgängerstudien HIT-GBM-A-D über einen Untersuchungszeitraum von 1998 - 2012. Alle Erst-MRTs und alle 3-monatige follow-up-Untersuchungen wurden statistisch ausgewertet und mit Hilfe von Kaplan-Meier-Kurven Überlebenswahrscheinlichkeiten für das OS und EFS bestimmt, sowie anschließendem Gruppenvergleich im Log- Rank-Test. Als prognostisch günstig erwiesen sich ein Erkrankungsalter bei Diagnosestellung unter 3 Jahren, sowie eine Therapie nach SKK-Schema. Auch eine fehlende Kontrastmittelaufnahme bei Diagnosestellung und eine große Tumorfläche zeigten bessere Überlebenszeiten. Dagegen hatten weder das Geschlecht, noch die Histologie, noch eine max. Flächen- oder Volumenreduktion Einfluss auf die Überlebenszeiten der betroffenen Kinder. N2 - Brainstem tumors are the most common solid neoplasm in childhood. Especially diffuse intrinsic brainstem gliomas occure diffusely in the pons. Subsequently they are difficult to treat and characterized by a dismal prognosis. More than 90% of children die within 2 years of diagnosis. The aim of this retrospective study was to find any predictive imaging or epidemiological features of overall and progression free survival, which could be used as prognostic markers. Data were analyzed from 253 children with newly diagnosed pontine glioma registered in HIT-GBM database, including the prospective multi-center studies HIT- GBM A-D and HIT-HGG 2007, from 1998-2012. To evaluate prognostic values, we performed a Kaplan-Meier survival analysis (log- rank test) that incorporated all initial MRIs and 3 month-follow-up MRIs. Favorable prognostic factors seemed to be an age younger than 3 years, as well as a therapy according to SKK, a large tumor area and absence of enhancement at baseline. But there was no survival difference between males and females. Neither histological grade, nor a maximum reduced tumor area or volume have shown a prognostic relevance. KW - DIPG KW - diffus intrinsisches Ponsgliom KW - prognostische Marker KW - MRT KW - brainstem glioma KW - prognostic marker on MRI Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-185505 ER - TY - JOUR A1 - Busch, Albert A1 - Tschernitz, Sebastian A1 - Thurner, Anette A1 - Kellersmann, Richard A1 - Lorenz, Udo T1 - Fatal Paraneoplastic Embolisms in Both Circulations in a Patient with Poorly Differentiated Neuroendocrine Tumour JF - Case Reports in Vascular Medicine N2 - Arterial embolism with lower limb ischemia is a rare manifestation of paraneoplastic hypercoagulability in cancer patients. We report a unique case of fatal thromboembolism involving both circulations associated with a poorly differentiated neuroendocrine tumor of the lung with rapid progress despite high doses of unfractioned heparin and review the current literature on anticoagulative regimen in tumour patients. KW - Medizin Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-97335 ER - TY - JOUR A1 - Buder, Kristina A1 - Lapa, Constantin A1 - Kreissl, Michael C. A1 - Schirbel, Andreas A1 - Herrmann, Ken A1 - Schnack, Alexander A1 - Bröcker, Eva-Bettina A1 - Goebeler, Matthias A1 - Buck, Andreas K. A1 - Becker, Jürgen C. T1 - "Somatostatin receptor expression in Merkel cell carcinoma as target for molecular imaging" N2 - Background Merkel cell carcinoma (MCC) is a rare cutaneous neoplasm with increasing incidence, aggressive behavior and poor prognosis. Somatostatin receptors (SSTR) are expressed in MCC and represent a potential target for both imaging and treatment. Methods To non-invasively assess SSTR expression in MCC using PET and the radiotracers [68Ga]DOTA-D-Phe1-Tyr3-octreotide (DOTATOC) or -octreotate (DOTATATE) as surrogate for tumor burden. In 24 patients with histologically proven MCC SSTR-PET was performed and compared to results of computed tomography (CT). Results SSTR-PET detected primary and metastatic MCC lesions. On a patient-based analysis, sensitivity of SSTR-PET was 73% for nodal metastases, 100% for bone, and 67% for soft-tissue metastases, respectively. Notably, brain metastases were initially detected by SSTR-PET in 2 patients, whereas liver and lung metastases were diagnosed exclusively by CT. SSTR-PET showed concordance to CT results in 20 out of 24 patients. Four patients (17%) were up-staged due to SSTR-PET and patient management was changed in 3 patients (13%). Conclusion SSTR-PET showed high sensitivity for imaging bone, soft tissue and brain metastases, and particularly in combination with CT had a significant impact on clinical stage and patient management. KW - Merkel cell carcinoma KW - Molecular imaging KW - Somatostatin receptor expression KW - Positron emission tomography Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-110326 ER - TY - THES A1 - Buchner, Stefan T1 - Quantitative 31P-MR-Spektroskopie am menschlichen Herzen und Etablierung von SLOOP am Skelettmuskel T1 - Quantitative 31P-MR-Spectroscopy of the human myocardium and establishment of SLOOP on skeletal muscle N2 - Die vorliegende Arbeit setzt sich mit dem Einsatz der 31P-Magnetresonanzspektroskopie (MRS) zur Untersuchung des menschlichen Herz- und Skelettmuskelstoffwechsels auseinander: [1] Mit der Anwendung und Implementierung der akquisitionsgewichteten CSI (AW-CSI) am menschlichen Herzen konnten wir den Einsatz dieser neuen Methode zur 31P-MR-Bildgebung am klinischen MR-Gerät etablieren. [2] Mit dem erstmaligen Einsatz von SLOOP am Skelettmuskel zur nicht-invasiven Quantifizierung des Energiestoffwechsels mit 31P-MRS erarbeiteten wir neue Untersuchungsprotokolle und konnten sie erfolgreich bei Probanden anwenden. [3] Mit der 31P-MRs konnten wir durch Bestimmung des PCr/ATP Verhältnisses Einflüsse und Veränderungen im Energiestoffwechsel sowohl im infarzierten als auch im nicht-infarzierten Myokard bei Patienten mit vitalem und avitalem anterioren Infarkt nachweisen (FAST). [4] Mit der klinischen Anwendung von SLOOP wurden subklinische Stoffwechselveränderungen bei Patienten mit multipler Sklerose (MS) und bei mit Mitoxantron (MX) therapierten MS-Patienten eruiert. [5] Mit dem erstmalig kombinierten Einsatz von SLOOP bei neuromuskulären Erkrankungen wie myotoner Dystrophie (DM1) und proximaler myotoner Myopathie (PROMM/DM2) wurden Zusammenhänge zwischen Krankheitsdauer, Krankheitsverlauf, Muskelschwäche und dem kardialen und skelettmuskulären Energiestoffwechsel untersucht, um zusätzliche Informationen zum Verständnis der Pathogenese und Entwicklung von DM1 und PROMM/DM2 zu gewinnen. N2 - The purpose of the study was KW - SLOOP KW - PROMM KW - DM KW - MS KW - Mitoxantron KW - AW-CSI KW - 31P KW - MR KW - Spektroskopie KW - PCr KW - ATP KW - Myokardinfarkt KW - SLOOP KW - PROMM KW - DM KW - MS KW - Mitoxantrone KW - AW-CSI KW - 31P KW - MR KW - spectroscopy KW - PCr KW - ATP KW - myocardial infarction Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-9071 ER - TY - THES A1 - Buchberger, Miriam T1 - Stellenwert der Computertomographie im Staging der Sigmadivertikulitis T1 - CT staging in sigmoid diverticulitis N2 - Zielsetzung: Wie genau kann die Computertomographie die einzelnen Stadien der Sigmadivertikulitis abbilden? Inwieweit ist eine Übereinstimmung befunderabhängig? Material und Methoden: Grundlage dieser Arbeit waren die Daten von 91 Patienten (43 Männer und 48 Frauen, Durchschnittalter: 60,4 Jahre), die im Zeitraum August 2008 bis Mai 2010 aufgrund einer Sigmadivertikulitis operiert wurden. Das prätherapeutisch mittels Computertomographie (Hansen und Stock-Klassifikation)diagnostizierte Stadium wurde mit dem histopathologisch bestimmten Stadium auf eine Übereinstimmung hin verglichen. Zudem wurden alle CT-Bilder von einem zweiten Radiologen nachbefundet und auf eine Übereinstimmung mit dem Befund des Erstbefunders verglichen. Ergebnisse: Die Sensitivität für das phlegmonöse Stadium (H&S IIA) lag bei 83,3%, für das Stadium der gedeckten Perforation (H&S IIB) bei 71,4% und 72,7% für das chronisch-rezidivierende Stadium (H&S III). Die Spezifität lag bei 83,5% für Stadium IIA, 81,0% für Stadium IIB und 92,7% für Stadium III. Die Sensitivität und Spezifität für Stadium IIC (freie Perforation) lag bei 100%. Bei zehn Patienten kam es seitens der Computertomographie zu einer Unterschätzung des Entzündungsausmaßes: hier wurde anhand der CT ein histopathologisch verifiziertes Stadium IIB als Stadium IIA klassifiziert. Der Kappa-Wert der Zwischenbeobachter-Korrelation lag bei 0,598. Zusammenfassung: Die Computertomographie ist insgesamt ein zuverlässiges radiologisches Verfahren in der Diagnostik der einzelnen Divertikulitis-Stadien, zeigt aber, insbesondere in der Diagnostik des Stadiums IIB Defizite im Sinne einer Unterschätzung des Entzündungsausmaßes. Auch die moderate Zwischenbeobachter-Übereinstimmung hebt mögliche Defizite der CT im Staging der Sigmadivertikulitis hervor. N2 - Purpose To assess accuracy of CT in the diagnosis of sigmoid diverticulitis and to evaluate interobserver correlation Methods and Materials This study included 91 patients (43 men and 48 women; median age 60.4 years) who underwent resection for sigmoid diverticulitis from August 2008 to May 2010. The preoperative stage was compared with intraoperative and histological reports utilizing the Hansen and Stock-classification (HS). All CT scans were interpreted by two radiologists, and we compared their reports in regard of agreement. Results The sensitivity in detecting the phlegmonous type (HS IIA) was 83.3%, for the covered perforation (HS IIB) 71.4% and 72.7% for the chronically recurrent diverticulitis (HS type III). The calculated specifity was 83.5% for type IIA, 81.0% for type IIB and 92.7% for type III. In the presence of free perforation (HS type IIC) we found a sensitivity and specifity of 100%. In the covered perforation type CT often leads to an underestimation of the findings. In ten cases the CT was not able to show a histopathologically verified covered perforation. Kappa statistics showed that radiologists only agreed moderately in their diagnosis (kappa=0.598). Conclusion CT is an accurate tool for staging in sigmoid diverticulitis, but shows especially in diagnosing type IIB a deficit in terms of an understaging. Moderate interobserver agreement also highlights potential difficulties in staging sigmoid diverticulitis by CT. KW - Divertikulitis KW - Sigmadivertikulitis KW - Computertomographie Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-162486 ER - TY - THES A1 - Brenner, Sophie Anna T1 - Optimierte Lungenbildgebung an einem offenen MRT bei Patienten mit Mukoviszidose - Darstellung der Morphologie und Funktion T1 - Optimized lung imaging at an open-design 0.2 T MR system in Cystic fibrosis: morphological and functional imaging N2 - Das Ziel dieser Arbeit war die Evaluierung von morphologischen und funktionellen Techniken zur Untersuchung der Lunge am Niederfeld MRT bei Patienten mit Mukoviszidose. Patienten mit Mukoviszidose und lungengesunde Probanden wurden an einem Niederfeld-MRT (0,2 Tesla) mittels coronaren TrueFISP, FLASH 2D und FLASH 3D Sequenzen untersucht. T1 und T2*-Messungen wurden während Atmung von Raumluft und Atmung von 100 % Sauerstoff durchgeführt und die Parameterkarten pixelweise berechnet. Die für die Lungenbildgebung am Niederfeld-MRT optimierten 2D und 3D FLASH Sequenzen zeigten ein signifikant besseres Signalverhalten als die Standardsequenz TrueFISP. Zur Beurteilung der Parenchymveränderungen wurde ein MR-Score in Anlehnung an den Chrispin-Norman-Score angewandt. Es zeigte sich eine gute Korrelation zwischen dem MR-Score der FLASH-Sequenzen und dem etablierten CN-Score der konventionellen Bildgebung mit einer geringen Interobservariabiliät für die 2D und 3D FLASH Sequenzen. Schließlich konnte eine O2-gestütze funktionelle Bildgebung der Lunge bei Patienten mit Mukoviszidose am offenen Niederfeld-MRT etabliert werden. Es zeigten sich gute Korrelationen zwischen der relativen Änderung der T1 Relaxationszeit und der spirometrisch bestimmten Lungenfunktion. Ein solcher Zusammenhang konnte für die T2*-Messungen nicht hergestellt werden. Aufgrund der Patientenfreundlichkeit ist diese Technik insbesondere für die Untersuchung von Kindern geeignet. N2 - The purpose of the present thesis was to evaluate the clinical relevance of morpholocical and functional MRI of the human lung using an open-designed magnet system for patients with cystic fibrosis. Such patients and healthy volunteers were investigated in a low-field (0,2 Tesla) MR-scanner by TrueFISP, FLASH 2D und FLASH 3D sequences (Magnetom Open 0,2 Tesla, Siemens Medical Solutions, Erlangen, Germany). For functional lung imaging the patients and volunteers alternately breathed room air and 100 % oxygen. All images were fitted pixel by pixel and T1 and T2* parameter maps were generated. The optimized FLASH 2D and 3D sequences demonstrated a significantly higher signal-to-noise ratio in comparison to TrueFISP sequence. The here proposed modified CN-Score for low-field MRI correlated well with the established score of Chrispin and Norman in CXR and showed a low interobserver variability for FLASH 2D und FLASH 3D sequences. Oxygen-enhanced T1 und T2* mapping of the human lung was successfully etablished at an open low field scanner in patients with cystic fibrosis. Observed relative changes of the average pulmonary relaxation times T1 and T2* were related to pulmonary function tests. The measured T1 values were in good agreement with the severity of disease in CF defined by the pulmonary function test. This was not the case for navigated T2* mapping. The open design provides superior patient comfort and relieves the examination of children. KW - MRT KW - Lunge KW - Mukoviszidose KW - Morphologie KW - Ventilation KW - Sauerstoff KW - 0 KW - 2 Tesla KW - mri KW - lung KW - cystic fibrosis KW - oxygen-enhanced Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-71805 ER - TY - THES A1 - Brackertz, Anita T1 - Absolutquantifizierung der myokardialen Perfusion in Ruhe und unter Adenosin-induziertem Stress mittels First-Pass MR-Bildgebung T1 - Absolute quantification of myocardial perfusion at rest and under adenosine stress by means of first-pass MR-Imaging N2 - In der Diagnostik und Therapie der KHK sind das frühzeitige Erkennen und die Beurteilung funktioneller Folgen atherosklerotischer Veränderungen von großer Bedeutung. Die First-Pass MR-Bildgebung ermöglicht Aussagen über die myokardiale Perfusion und damit die hämodynamische Relevanz einer Koronarstenose. In der vorliegenden Arbeit wurden quantitative Werte für die myokardiale Durchblutung gesunder Probanden unter Adenosin-induziertem Stress und in Ruhe unter Einsatz der Präbolustechnik bestimmt. Eine exakte Darstellung der arteriellen Inputfunktion wurde durch einen Kontrastmittelbolus in niedriger Dosierung erreicht, die Verwendung höherer Kontrastmitteldosen führte dagegen zu einem verbesserten Signal-zu-Rausch-Verhältnis im Myokard. Die Absolutwerte der myokardialen Perfusion unter Stressbedingungen und in Ruhe wie auch die myokardiale Perfusionsreserve zeigten vergleichbare Mittelwerte, wiesen aber eine geringere Streubreite im Vergleich zu früheren MR Studien auf und waren vergleichbar mit in PET-Studien erzielten Ergebnissen. Weiterhin wurden unter Verwendung dieser Methode Werte für das myokardiale Verteilungsvolumen des Kontrastmittels als wichtiger Parameter in der Differenzierung von gesundem und infarziertem Herzmuskelgewebe ermittelt und die Laufzeit der Boluspassage nach Injektion in Ruhe und unter Stress bestimmt, die zur Unterscheidung von antegrad perfundiertem und von über Kollateralen versorgtem Myokard dienen kann. Mit Hilfe der MRT war es auch möglich, Unterschiede zwischen subendo- und subepimyokardialer Perfusion zu quantifizieren. Die erzielten Ergebnisse entsprechen bisher publizierten Werten, die mit anderen Modalitäten gewonnen wurden. Der Vergleich der absoluten Perfusion bei verminderter zeitlicher Auflösung mit den bei hoher zeitlicher Auflösung gemessenen Werten ergab nur geringfügige Abweichungen der Ergebnisse voneinander. Dadurch eröffnet sich die Möglichkeit, durch die Zeitersparnis mehrere Schichten abwechselnd bei verschiedenen Herzschlägen zu messen und damit eine erweiterte Abdeckung des linksventrikulären Myokards zu erreichen. Durch die quantitative Auswertung der First-Pass MR-Perfusionsmessung stellt die beschriebene Methode eine vielversprechende Option im Bereich der nichtinvasiven Diagnostik verschiedener myokardialer Erkrankungen dar. N2 - The detection and the assessment of the functional significance of atherosclerosis are of great importance in diagnosis and therapy of coronary artery disease. First-Pass MR-Imaging provides information about myocardial perfusion and the hemodynamic relevance of coronary artery stenoses. The aim of this work was to establish quantitative values of myocardial perfusion in healthy volunteers under adenosine induced stress and at rest using the prebolus technique. An exact determination of the arterial input function was achieved by injection of a low-dose bolus of contrast agent. High-dose bolus administration lead to an improved signal-to-noise ratio in the myocardium. Absolute values of myocardial perfusion under stress and at rest as well as the myocardial perfusion reserve showed comparable mean values as previous MR studies. However, the standard deviation was decreased compared to previous MR studies but similar to those of PET studies. Furthermore, values of the myocardial distribution volume of the contrast agent could be determined, which is an important parameter for differentiating between healthy and infarcted myocardium. Additionally, the duration of the bolus passage from the left ventricular lumen to the arrival in the myocardium was determined. By establishing the regional delay of contrast agent arrival, it is possible to differentiate between antegradely perfused and collateral-dependent myocardium. MRT also allowed the quantification of differences between subendocardial und subepicardial perfusion. The achieved results matches well previously published values obtained with other modalities. The comparison of perfusion values using only the images acquired at every 2nd, 3rd or 4th heartbeat and those measured at every heartbeat resulted in only minor changes. Consequently, it may become possible to scan several slices at alternating heartbeats, thereby achieving an increased coverage of the left ventricular myocardium. The absolute quantification of myocardial perfusion by means of MR-First-Pass-Imaging presents a promising non-invasive option in the diagnosis of myocardial diseases. KW - NMR-Tomographie KW - Perfusion KW - Herzmuskel KW - Quantifizierung KW - Stress KW - MRI KW - perfusion KW - myocardium KW - quantification KW - stress Y1 - 2008 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-34921 ER - TY - THES A1 - Boldt, Cornelia Klara T1 - Diffusionsgewichtete MRT Bildgebung bei Erkrankungen im Zahn-Mund-Kiefer/Hals-Nasen-Ohren Bereich T1 - Diffusion weighted magnetic resonance imaging of lesions in the head and neck region N2 - Zielsetzung: Die Zielsetzung dieser Arbeit war es zu beurteilen, inwieweit die Diffusionsgewichtete MRT Bildgebung bei der Differenzierung zwischen malignen und benignen Erkrankungen im Kopf-Hals Bereich nützlich sein kann. Außerdem ging es um die Sammlung der mittleren ADC-Werte von verschiedenen Diagnosen. Material und Methoden: Es wurden diffusionsgewichtete Bilder mit einer SE-EPI-Sequenz (b-Wert Paarung von 50 und 800 s/mm2, 1,5T) verglichen. 53 Plattenepithelcarzinome (PeCa), 21 benigne Befunde, 6 Lymphome, 6 Hämangiome, 6 Zysten Ergebnis: Die mittlere ADC- Wert (MW x10-3mm²/s +/-SD) der PeCa betrug 0.967 (0.118), der benignen Läsionen 1.458 (0.371), der Lymphome 0.649 (0.167), der Hämangiome 1.654 (0.254), der Zysten 2.310 (0.655) Der mittlere ADC-Wert der PeCa war signifikant kleiner als der der benignen Läsionen. Ein ADC- Wert von 1.202x10-3mm²/s kann als Grenzwert für die Differenzierung zwischen benignen und malignen Läsionen im Kopf-Hals Bereich angesehen werden. Schlussfolgerung: Die ADC-Werte können für die Charakterisierung von Läsionen im Kopf-Hals Bereich genutzt werden. N2 - Objective: The objective of this study was to evaluate the utility of diffusion weighted MR imaging (DWI) in the differentiation between malignant and benign lesions in the head and neck region. Furthermore get values for the apparent diffusion coefficient (ADC) for different diagnoses. Material and methods: We compared diffusion weighted images using SE-EPI sequences (b values of 50 and 800 s/mm2, 1,5T). 53 squamosa cell carcinomas (SSC), 21 benigne lesions, 6 malignant lymphomas, 6 hämangiomas, 6 cysts Results: The ADC values (mean x10-3mm²/s +/- SD) were 0.967 (0.118) in squamosal cell carcinomas (SSC), 1.458 (0.371) in benign lesions, 0.649 (0.167) in malignant lymphomas, 1.654 (0.254) in hämangiomas, 2.310 (0.655) in cysts. The mean ADC of SSC was significantly lower than of benign lesions. An ADC value of 1.202x10-3mm²/s may be the threshold value for differentiation between benign and malignant head and neck lesions. Conclusion: Measurement of ADCs may be used to characterize head and neck lesions. KW - DWI KW - ADC KW - DWI KW - head and neck KW - ADC Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-84303 ER - TY - THES A1 - Blättner, Katrin Ayara T1 - Quantifizierung myokardialer Fibrose in der Late Enhancement- MRT- manuell (Viewing) versus semiautomatisch (VPT3.0) T1 - Quantification of myocardial fibrosis in late enhancement mri- manual (Viewing) versus semi-automatic (VPT3.0) N2 - Die kontrastmittel- gestützte Late Enhancement- MRT ermöglicht die Darstellung myokardialer Veränderungen wie z.B. Ödem, Nekrose oder Fibrose. Ziel dieser Arbeit war es die semiautomatische Late Enhancement- Quantifizierung im Programm VPT 3.0 mit der manuellen Late Enhancement- Quantifizierung im Viewing- Programm zu vergleichen. Es wurden Late Enhancement- MRT- Datensätze von Patienten mit ischämischen (Myokardinfarkt) bzw. nicht- ischämischen Kardiomyopathien (Morbus Fabry, Morbus Hodgkin, Aortenklappenstenose) analysiert. Die Quantifizierung des Late Enhancement- Signals erfolgte manuell im Viewing- Programm und semiautomatisch unter Anwendung von VPT 3.0. Der Vergleich der Ergebnisse aus der manuellen Analyse und der semiautomatischen Analyse der Daten von Patienten nach Myokardinfarkt, mit kardialer Beteiligung bei Morbus Fabry und bei Z.n. anteriorer Mantelfeldbestrahlung bei Morbus Hodgkin, zeigte eine hohe Übereinstimmung sowie eine gute Korrelation der Werte beider Methoden. Eine valide Late Enhancement- Quantifizierung bei Patienten mit Aortenklappenstenose war sowohl in der manuellen, wie auch in der semiautomatischen Methode nicht möglich. Dies ist unter anderem auf das kleinfleckige, diffus flächige Verteilungsmuster im Rahmen der hier auftretenden konzentrischen Hypertrophie zurückzuführen. Des Weiteren konnte eine geringe Intraobservervariabilität aufgezeigt werden. Das semiautomatische Programm VPT3.0 ermöglicht eine genaue, mit der manuellen Methode gut korrelierende, Quantifizierung von Late Enhancement bei ischämischen und nicht- ischämischen Kardiomyopathien. Davon ausgenommen ist die Aortenstenose. N2 - Contrast agent-based late enhancement mri allows the depiction of myocardial changes e.g. edema, fibrosis or necrosis. The purpose of this thesis was to compare semi- automatic quantification of late enhancement using VPT3.0 with manual quantification using viewing- program. Late enhancement mri data of patients with ischemic (myocardial infarction) and non-ischemic cardiomyopathy (fabry's disease, hodgkin's lymphoma and aortic stenosis) were analyzed. The quantification of late enhancement signal was accomplished manually using viewing program and semi-automatically using VPT 3.0. The comparison of the results from the analysis of patients‘ data suffering from myocardial infarction, cardiac involvement in fabry’s disease and after anterior mantle field irradiation for hodgkin’s lymphoma, showed high correlation for both methods. A valid quantification of late enhancement in patients with aortic stenosis was not possible in most cases. This can, in part, be attributed to the blotchy and patchy pattern of the fibrotic changes appearing due to concentric hypertrophy. Additionally, a low intraobserver variability was demonstrated. The semi- automatic program VPT 3.0 provides an accurate, with the manual technique well- correlated method of quantifying late enhancement in ischemic and nonischemic cardiomyopathies, excluding aortic stenosis. KW - NMR-Tomographie KW - Kontrastmittel KW - Quantifizierung KW - Herzinfarkt KW - Fabry-Krankheit KW - Lymphogranulomatose KW - Aortenstenose KW - Late Enhancement KW - mri KW - contrast agent KW - late enhancement KW - quantification KW - myocardial infarction KW - fabry's disease KW - hodgkin's lymphoma KW - aortic stenosis Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-72465 ER - TY - JOUR A1 - Bluemel, Christina A1 - Linke, Fraenze A1 - Herrmann, Ken A1 - Simunovic, Iva A1 - Eiber, Matthias A1 - Kestler, Christian A1 - Buck, Andreas K. A1 - Schirbel, Andreas A1 - Bley, Thorsten A. A1 - Wester, Hans-Juergen A1 - Vergho, Daniel A1 - Becker, Axel T1 - Impact of \(^{68}\)Ga-PSMA PET/CT on salvage radiotherapy planning in patients with prostate cancer and persisting PSA values or biochemical relapse after prostatectomy JF - EJNMMI Research N2 - Background Salvage radiotherapy (SRT) is clinically established in prostate cancer (PC) patients with PSA persistence or biochemical relapse (BCR) after prior radical surgery. PET/CT imaging prior to SRT may be performed to localize disease recurrence. The recently introduced \(^{68}\)Ga-PSMA outperforms other PET tracers for detection of recurrence and is therefore expected also to impact radiation planning. Forty-five patients with PSA persistence (16 pts) or BCR (29 pts) after prior prostatectomy, scheduled to undergo SRT of the prostate bed, underwent \(^{68}\)Ga-PSMA PET/CT. The median PSA level was 0.67 ng/ml. The impact of \(^{68}\)Ga-PSMA PET/CT on the treatment decision was assessed. Patients with oligometastatic (≤5 lesions) PC underwent radiotherapy (RT), with the extent of the RT area and dose escalation being based on PET positivity. Results Suspicious lesions were detected in 24/45 (53.3 %) patients. In 62.5 % of patients, lesions were only detected by 68Ga-PSMA PET. Treatment was changed in 19/45 (42.2 %) patients, e.g., extending SRT to metastases (9/19), administering dose escalation in patients with morphological local recurrence (6/19), or replacing SRT by systemic therapy (2/19). 38/45 (84.4 %) followed the treatment recommendation, with data on clinical follow-up being available in 21 patients treated with SRT. All but one showed biochemical response (mean PSA decline 78 ± 19 %) within a mean follow-up of 8.12 ± 5.23 months. Conclusions \(^{68}\)Ga-PSMA PET/CT impacts treatment planning in more than 40 % of patients scheduled to undergo SRT. Future prospective studies are needed to confirm this significant therapeutic impact on patients prior to SRT. KW - prostate cancer KW - salvage radiotherapy KW - PSMA KW - PET/CT KW - recurrence Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-147798 VL - 6 IS - 78 ER - TY - THES A1 - Blaßhofer, Sophia Katharina Charlotte T1 - Rezidivmuster bei Kindern mit Medulloblastom T1 - Recurrence Pattern in Children with Medulloblastoma N2 - Ziel der vorliegenden Arbeit ist es, das Rezidivmuster der Medulloblastome aufzuzeigen. Die Bedeutung prognostischer Faktoren, wie Therapie oder initiale Erkrankungsausdehnung soll im Zusammenhang mit dem Auftreten eines Rezidivs oder einer Progression näher untersucht werden. Es handelt sich um ein Patientenkollektiv von 40 Kindern mit einem Rezidiv eines Medulloblastoms. Die Patienten sind Teil des HIT 2000 Kollektivs, ein Patient war Teil der HIT ´91 Studie, 7 waren Beobachtungspatienten. Die Altersverteilung der Rezidivpatienten unterschied sich von der Altersverteilung aller HIT 2000-Studienpatienten. Die Patienten in der Gruppe der unter Vierjährigen mit einem Rezidiv waren signifikant jünger als die des gesamten Kollektivs unter vier Jahren. Bei den älteren Kindern war der Unterschied nicht signifikant. Von insgesamt 40 Kindern fanden sich acht Patienten mit Lokalrezidiv (20%) und 32 Patienten mit einem Rezidiv in Form einer Meningeose (80%). Bei Patienten mit Lokalrezidiv zeigte ein postoperativ verbliebener Resttumor keinen Einfluß auf das Entstehen eines Lokalrezidivs. 100% der Patienten, die Angaben zu einem verbliebenen Resttumor hatten, waren S0 reseziert. Fünf der acht Kinder wurden aufgrund ihres jungen Alters nicht bestrahlt. 32 Patienten (80%) zeigten eine Meningeose als Rezidiv auf. 73,3% der Patienten wiesen bereits initial eine Disseminationen in den Meningen auf. 50% der Patienten (n=16) boten die Dissemination im frontalen oder frontobasalen Bereich. Alle lokal begrenzten, frontalen Meningeoseherde traten an einer vorher nicht betroffenen Stelle auf. Es ließen sich keine Hinweise auf eine Unterdosierung der Radiatio als Ursache finden. Ein Einfluß der Chemotherapie unter Berücksichtigung der durch die Liquorzirkulation bedingten Schwankungen in den Wirkspiegeln bleibt zu klären und wird Gegenstand weiterer Studien sein müssen. N2 - We have retrospectively analyzed 38 consecutive patients with a recurrence of medulloblastoma treated according to a national multicenter protocol. Two of 38 patients studied relapsed twice and were thus counted twice resulting in a total number of 40 patients. Most patients (n=32) were treated according to the current national treatment study for medulloblastomas (HIT 2000), one patient was treated according to the preceding trial Hit’91 and 7 children were observational patients of the HIT 2000 study. All patients with relapse younger than four years of age were significantely younger than all patients with medulloblastoma registered in HIT 2000. 38 children treated for medulloblastoma showed 40 events of recurrences. 8 patients relapsed with an isolated local recurrence of the tumour. We did not find any correlation to an incomplete surgical removal or a violation to the treatment protocol. 50% of these children were younger than 4 years at the time of initial presentation and thus were not treated primarily with radiotherapy. 32 events were recurrences with a meningeal dissemination. 50% of these recurrences were found in the frontal region and 25% as isolated nodular frontal and frontobasal meningeal disease. We could not find any correlation to possible treatment violations especially to a lower irradiation dose of the frontobasal region. Other explanations, e.g. reduced biodistribution of chemotherapeutic agents to these areas have to be sought for. KW - Rezidiv KW - Neuroblastom KW - Hirntumor KW - Kleinhirntumor KW - Medulloblastom KW - Rezidivmuster KW - recurrence KW - pattern KW - medulloblastoma Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-38636 ER - TY - JOUR A1 - Biederer, Jürgen A1 - Mirsadraee, S. A1 - Beer, M. A1 - Molinari, F. A1 - Hintze, C. A1 - Bauman, G. A1 - Both, M. A1 - Van Beek, E. J. R. A1 - Wild, J. A1 - Puderbach, M. T1 - MRI of the lung (3/3)—current applications and future perspectives JF - Insights into Imaging N2 - Background MRI of the lung is recommended in a number of clinical indications. Having a non-radiation alternative is particularly attractive in children and young subjects, or pregnant women. Methods Provided there is sufficient expertise, magnetic resonance imaging (MRI) may be considered as the preferential modality in specific clinical conditions such as cystic fibrosis and acute pulmonary embolism, since additional functional information on respiratory mechanics and regional lung perfusion is provided. In other cases, such as tumours and pneumonia in children, lung MRI may be considered an alternative or adjunct to other modalities with at least similar diagnostic value. Results In interstitial lung disease, the clinical utility of MRI remains to be proven, but it could provide additional information that will be beneficial in research, or at some stage in clinical practice. Customised protocols for chest imaging combine fast breath-hold acquisitions from a “buffet” of sequences. Having introduced details of imaging protocols in previous articles, the aim of this manuscript is to discuss the advantages and limitations of lung MRI in current clinical practice. Conclusion New developments and future perspectives such as motion-compensated imaging with self-navigated sequences or fast Fourier decomposition MRI for non-contrast enhanced ventilation- and perfusion-weighted imaging of the lung are discussed. Main Messages • MRI evolves as a third lung imaging modality, combining morphological and functional information. • It may be considered first choice in cystic fibrosis and pulmonary embolism of young and pregnant patients. • In other cases (tumours, pneumonia in children), it is an alternative or adjunct to X-ray and CT. • In interstitial lung disease, it serves for research, but the clinical value remains to be proven. • New users are advised to make themselves familiar with the particular advantages and limitations. KW - functional imaging KW - magnetic resonance imaging KW - cystic fibrosis KW - pulmonary embolism KW - tumor KW - infiltrate Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124348 VL - 3 IS - 4 ER - TY - JOUR A1 - Biederer, J. A1 - Beer, M. A1 - Hirsch, W. A1 - Wild, J. A1 - Fabel, M. A1 - Puderbach, M. A1 - Van Beek, E. J. R. T1 - MRI of the lung (2/3). Why … when … how? JF - Insights into Imaging N2 - Background Among the modalities for lung imaging, proton magnetic resonance imaging (MRI) has been the latest to be introduced into clinical practice. Its value to replace X-ray and computed tomography (CT) when radiation exposure or iodinated contrast material is contra-indicated is well acknowledged: i.e. for paediatric patients and pregnant women or for scientific use. One of the reasons why MRI of the lung is still rarely used, except in a few centres, is the lack of consistent protocols customised to clinical needs. Methods This article makes non-vendor-specific protocol suggestions for general use with state-of-the-art MRI scanners, based on the available literature and a consensus discussion within a panel of experts experienced in lung MRI. Results Various sequences have been successfully tested within scientific or clinical environments. MRI of the lung with appropriate combinations of these sequences comprises morphological and functional imaging aspects in a single examination. It serves in difficult clinical problems encountered in daily routine, such as assessment of the mediastinum and chest wall, and even might challenge molecular imaging techniques in the near future. Conclusion This article helps new users to implement appropriate protocols on their own MRI platforms. Main Messages • MRI of the lung can be readily performed on state-of-the-art 1.5-T MRI scanners. • Protocol suggestions based on the available literature facilitate its use for routine • MRI offers solutions for complicated thoracic masses with atelectasis and chest wall invasion. • MRI is an option for paediatrics and science when CT is contra-indicated KW - magnetic resonance imaging KW - lung KW - sequence imaging protocol Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124268 VL - 3 IS - 4 ER - TY - JOUR A1 - Baur, Johannes A1 - Schedelbeck, Ulla A1 - Pulzer, Alina A1 - Bluemel, Christina A1 - Wild, Vanessa A1 - Fassnacht, Martin A1 - Steger, U. T1 - A case report of a solitary pancreatic metastasis of an adrenocortical carcinoma JF - BMC Surgery N2 - Background Solitary metastases to the pancreas are rare. Therefore the value of resection in curative intention remains unclear. In the literature there are several promising reports about resection of solitary metastasis to the pancreas mainly of renal origin. Case presentation Here we report for the first time on the surgical therapy of a 1.5 cm solitary pancreatic metastasis of an adrenocortical carcinoma. The metastasis occurred almost 6 years after resection of the primary tumor. A partial pancreatoduodenectomy was performed and postoperatively adjuvant mitotane treatment was initiated. During the follow-up of 3 years after surgery no evidence of tumor recurrence occurred. Conclusion Resection of pancreatic tumors should be considered, even if the mass is suspicious for metastatic disease including recurrence of adrenocortical cancer. KW - surgical treatment KW - adrenocortical KW - carcinoma metastases to pancreas Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-126130 VL - 15 IS - 93 ER - TY - JOUR A1 - Baur, Johannes A1 - Ritter, Christian O. A1 - Germer, Christoph-Thomas A1 - Klein, Ingo A1 - Kickuth, Ralph A1 - Steger, Ulrich T1 - Transarterial chemoembolization with drug-eluting beads versus conventional transarterial chemoembolization in locally advanced hepatocellular carcinoma JF - Hepatic Medicine N2 - Purpose: In hepatocellular carcinoma patients with large or multinodal tumors, where curative treatment options are not feasible, transarterial therapies play a major role. Transarterial chemoembolization (TACE) with drug-eluting beads (DEB-TACE) is a promising new approach due to higher intratumoral and lower systemic concentration of the chemotherapeutic agent compared to conventional TACE (cTACE). Patients and methods: In a retrospective analysis, 32 patients with hepatocellular carcinoma who received either DEB or a cTACE were compared regarding survival time, disease recurrence, and side effects such as pain and fever. Results: No significant differences could be detected between the cTACE and DEB-TACE groups with regard to mean hospital stay, appearance of postinterventional fever, or 30-day mortality. However, the application of intravenous analgesics as postinterventional pain medication was needed more often in patients treated with DEB-TACE (57.1% vs 12.5%, P=0.0281). The overall median survival after the initial procedure was 10.8 months in the cTACE group and 9.2 months in the DEB-TACE group, showing no significant difference. Conclusion: No survival benefit for patients treated with either DEB-TACE or cTACE was observed. Surprisingly, a higher rate of postinterventional pain could be detected after DEB-TACE. KW - transarterial chemoembolization KW - hepatocellular carcinoma KW - drug-eluting beads Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146553 VL - 2016 IS - 8 ER - TY - JOUR A1 - Bartmann, Catharina A1 - Janaki Raman, Sudha R. A1 - Flöter, Jessica A1 - Schulze, Almut A1 - Bahlke, Katrin A1 - Willingstorfer, Jana A1 - Strunz, Maria A1 - Wöckel, Achim A1 - Klement, Rainer J. A1 - Kapp, Michaela A1 - Djuzenova, Cholpon S. A1 - Otto, Christoph A1 - Kämmerer, Ulrike T1 - Beta-hydroxybutyrate (3-OHB) can influence the energetic phenotype of breast cancer cells, but does not impact their proliferation and the response to chemotherapy or radiation JF - Cancer & Metabolism N2 - Background: Ketogenic diets (KDs) or short-term fasting are popular trends amongst supportive approaches for cancer patients. Beta-hydroxybutyrate (3-OHB) is the main physiological ketone body, whose concentration can reach plasma levels of 2–6 mM during KDs or fasting. The impact of 3-OHB on the biology of tumor cells described so far is contradictory. Therefore, we investigated the effect of a physiological concentration of 3 mM 3-OHB on metabolism, proliferation, and viability of breast cancer (BC) cells in vitro. Methods: Seven different human BC cell lines (BT20, BT474, HBL100, MCF-7, MDA-MB 231, MDA-MB 468, and T47D) were cultured in medium with 5 mM glucose in the presence of 3 mM 3-OHB at mild hypoxia (5% oxygen) or normoxia (21% oxygen). Metabolic profiling was performed by quantification of the turnover of glucose, lactate, and 3-OHB and by Seahorse metabolic flux analysis. Expression of key enzymes of ketolysis as well as the main monocarboxylic acid transporter MCT2 and the glucose-transporter GLUT1 was analyzed by RT-qPCR and Western blotting. The effect of 3-OHB on short- and long-term cell proliferation as well as chemo- and radiosensitivity were also analyzed. Results: 3-OHB significantly changed the oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) in BT20 cells resulting in a more oxidative energetic phenotype. MCF-7 and MDA-MB 468 cells had increased ECAR only in response to 3-OHB, while the other three cell types remained uninfluenced. All cells expressed MCT2 and GLUT1, thus being able to uptake the metabolites. The consumption of 3-OHB was not strongly linked to mRNA overexpression of key enzymes of ketolysis and did not correlate with lactate production and glucose consumption. Neither 3-OHB nor acetoacetate did interfere with proliferation. Further, 3-OHB incubation did not modify the response of the tested BC cell lines to chemotherapy or radiation. Conclusions: We found that a physiological level of 3-OHB can change the energetic profile of some BC cell lines. However, 3-OHB failed to influence different biologic processes in these cells, e.g., cell proliferation and the response to common breast cancer chemotherapy and radiotherapy. Thus, we have no evidence that 3-OHB generally influences the biology of breast cancer cells in vitro. KW - ketogenic diet KW - β-Hydroxybutyrate KW - ketone bodies KW - breast cancer KW - seahorse KW - metabolic profile KW - chemotherapy KW - ionizing radiation Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-175607 VL - 6 IS - 8 ER - TY - THES A1 - Baldauf, Tobias T1 - Radiologischer Routineultraschall bei Verdacht auf Appendizitis: Retrospektive Analyse der diagnostischen Wertigkeit T1 - Ultrasound diagnosis of appendicitis - a retrospective analysis of the it's diagnostic importance N2 - Der allgemeinradiologische Ultraschall leistet einen wichtigen Beitrag in der Routinediagnostik der akuten Appendizitis bei Kindern und Erwachsenen. Die Zusammenschau aller verfügbaren diagnostischen Befunde sollte zur Entscheidung für oder gegen eine Operation herangezogen werden. Die sonographische Untersuchung kann dazu beitragen, die Negativ Appendektomierate zu senken. N2 - Ultrasound diagnosis of appendicitis - a retrospective analysis of the it's diagnostic importance KW - Appendizitis Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-192231 ER - TY - JOUR A1 - Augustin, Anne Marie A1 - Wolfschmidt, Franziska A1 - Elsässer, Thilo A1 - Sauer, Alexander A1 - Dierks, Alexander A1 - Bley, Thorsten Alexander A1 - Kickuth, Ralph T1 - Color-coded summation images for the evaluation of blood flow in endovascular aortic dissection fenestration JF - BMC Medical Imaging N2 - Background To analyze the benefit of color-coded summation images in the assessment of target lumen perfusion in patients with aortic dissection and malperfusion syndrome before and after fluoroscopy-guided aortic fenestration. Methods Between December 2011 and April 2020 25 patients with Stanford type A (n = 13) or type B dissection (n = 12) and malperfusion syndromes were treated with fluoroscopy-guided fenestration of the dissection flap using a re-entry catheter. The procedure was technically successful in 100% of the cases and included additional iliofemoral stent implantation in four patients. Intraprocedural systolic blood pressure measurements for gradient evaluation were performed in 19 cases. Post-processed color-coded DSA images were obtained from all DSA series before and following fenestration. Differences in time to peak (dTTP) values in the compromised aortic lumen and transluminal systolic blood pressure gradients were analyzed retrospectively. Correlation analysis between dTTP and changes in blood pressure gradients was performed. Results Mean TTP prior to dissection flap fenestration was 6.85 ± 1.35 s. After fenestration, mean TTP decreased significantly to 4.96 ± 0.94 s (p < 0.001). Available systolic blood pressure gradients between the true and the false lumen were reduced by a median of 4.0 mmHg following fenestration (p = 0.031), with significant reductions in Stanford type B dissections (p = 0.013) and minor reductions in type A dissections (p = 0.530). A moderate correlation with no statistical significance was found between dTTP and the difference in systolic blood pressure (r = 0.226; p = 0.351). Conclusions Hemodynamic parameters obtained from color-coded DSA confirmed a significant reduction of TTP values in the aortic target lumen in terms of an improved perfusion in the compromised aortic region. Color-coded DSA might thus be a suitable complementary tool in the assessment of complex vascular patterns prevailing in aortic dissections, especially when blood pressure measurements are not conclusive or feasible. KW - angiography KW - fenestration KW - color-coding KW - aortic dissection KW - DSA KW - endovascular Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-301107 VL - 22 IS - 1 ER - TY - JOUR A1 - Augustin, Anne Marie A1 - Welsch, Stefan A1 - Bley, Thorsten Alexander A1 - Lopau, Kai A1 - Kickuth, Ralph T1 - Color-coded summation images in the evaluation of renal artery stenosis before and after percutaneous transluminal angioplasty JF - BMC Medical Imaging N2 - Background: Endovascular therapy is the gold standard in patients with hemodynamic relevant renal artery stenosis (RAS) resistant to medical therapy. The severity grading of the stenosis as well as the result assessment after endovascular approach is predominantly based on visible estimations of the anatomic appearance. We aim to investigate the application of color-coded DSA parameters to gain hemodynamic information during endovascular renal artery interventions and for the assessment of the procedures technical success. Methods: We retrospectively evaluated 32 patients who underwent endovascular renal artery revascularization and applied color-coded summation imaging on selected monochromatic DSA images. The differences in time to peak (dTTP) of contrast enhancement in predefined anatomical measuring points were analyzed. Furthermore, differences in systolic blood pressure values (SBP) and serum creatinine were obtained. The value of underlying diabetes mellitus as a predictor for clinical outcome was assessed. Correlation analysis between the patients gender as well as the presence of diabetes mellitus and dTTP was performed. Results: Endovascular revascularization resulted in statistically significant improvement in 4/7 regions of interest. Highly significant improvement of perfusion in terms of shortened TTP values could be found at the segmental artery level and in the intrastenotical segment (p<0.001), significant improvement prestenotical and in the apical renal parenchyma (p<0.05). In the other anatomic regions, differences revealed not to be significant. Differences between SBP and serum creatinine levels before and after the procedure were significant (p=0.004 and 0.0004). Patients ' gender as well as the presence of diabetes mellitus did not reveal to be predictors for the clinical success of the procedure. Furthermore, diabetes and gender did not show relevant correlation with dTTP in the parenchymal measuring points. Conclusions: The supplementary use of color-coding DSA and the data gained from parametric images may provide helpful information in the evaluation of the procedures ' technical success. The segmental artery might be a particularly suitable vascular territory for analyzing differences in blood flow characteristics. Further studies with larger cohorts are needed to further confirm the diagnostic value of this technique. KW - digital subtraction angiography KW - color-coded KW - endovascular KW - renal artery KW - PTA Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259086 VL - 21 IS - 1 ER - TY - JOUR A1 - Augustin, Anne Marie A1 - Lucius, Leonie Johanna A1 - Thurner, Annette A1 - Kickuth, Ralph T1 - Malignant obstruction of the inferior vena cava: clinical experience with the self-expanding Sinus-XL stent system JF - Abdominal Radiology N2 - Purpose To evaluate the technical and clinical outcome of Sinus-XL stent placement in patients with malignant obstruction syndrome of the inferior vena cava. Methods Between October 2010 and January 2021, 21 patients with different malignant primary disease causing inferior vena cava obstruction were treated with Sinus-XL stent implantation. Procedural data, technical and clinical outcome parameters were retrospectively analyzed. Results Technical success was 100%. Analysis of available manometry data revealed a significant reduction of the mean translesional pressure gradient following the procedure (p = 0.008). Reintervention rate was 4.8% (1/21). The available follow-up imaging studies showed primary and primary-assisted stent patency rates of 93% (13/14) and 100% (14/14), respectively. Major complications did not occur. The clinical success regarding lower extremity edema was 82.4% (14/17) for the first and 85.7% (18/21) for the last follow-up. Longer lengths of IVC obstruction were associated with reduced clinical improvement after the procedure (p = 0.025). Improvement of intraprocedural manometry results and lower extremity edema revealed only minor correlation. Ascites and anasarca were not significantly positively affected by the procedure. Conclusion Sinus-XL stent placement in patients with malignant inferior vena cava obstruction showed high technical success and low complication rates. Regarding the clinical outcome, significant symptom improvement could be achieved in lower extremity edema, whereas ascites and anasarca lacked satisfying symptom relief. Based on our results, this procedure should be considered as a suitable therapy in a palliative care setting for patients with advanced malignant disease. KW - endovascular KW - inferior vena cava KW - interventional procedures KW - oncology KW - palliative care KW - stent Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324951 VL - 47 IS - 10 ER -