@article{RufBeerKoestleretal.2019, author = {Ruf, Katharina and Beer, Meinrad and K{\"o}stler, Herbert and Weng, Andreas Max and Neubauer, Henning and Klein, Alexander and Platek, Kathleen and Roth, Kristina and Beneke, Ralph and Hebestreit, Helge}, title = {Size-adjusted muscle power and muscle metabolism in patients with cystic fibrosis are equal to healthy controls - a case control study}, series = {BMC Pulmonary Medicine}, volume = {19}, journal = {BMC Pulmonary Medicine}, doi = {10.1186/s12890-019-1039-8}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-200981}, pages = {269}, year = {2019}, abstract = {Background Skeletal muscle function dysfunction has been reported in patients with cystic fibrosis (CF). Studies so far showed inconclusive data whether reduced exercise capacity is related to intrinsic muscle dysfunction in CF. Methods Twenty patients with CF and 23 age-matched controls completed an incremental cardiopulmonary cycling test. Further, a Wingate anaerobic test to assess muscle power was performed. In addition, all participants completed an incremental knee-extension test with 31P magnetic resonance spectroscopy to assess muscle metabolism (inorganic phosphate (Pi) and phosphocreatinine (PCr) as well as intracellular pH). In the MRI, muscle cross-sectional area of the M. quadriceps (qCSA) was also measured. A subgroup of 15 participants (5 CF, 10 control) additionally completed a continuous high-intensity, high-frequency knee-extension exercise task during 31P magnetic resonance spectroscopy to assess muscle metabolism. Results Patients with CF showed a reduced exercise capacity in the incremental cardiopulmonary cycling test (VO2peak: CF 77.8 ± 16.2\%predicted (36.5 ± 7.4 ml/qCSA/min), control 100.6 ± 18.8\%predicted (49.1 ± 11.4 ml/qCSA/min); p < 0.001), and deficits in anaerobic capacity reflected by the Wingate test (peak power: CF 537 ± 180 W, control 727 ± 186 W; mean power: CF 378 ± 127 W, control 486 ± 126 W; power drop CF 12 ± 5 W, control 8 ± 4 W. all: p < 0.001). In the knee-extension task, patients with CF achieved a significantly lower workload (p < 0.05). However, in a linear model analysing maximal work load of the incremental knee-extension task and results of the Wingate test, respectively, only muscle size and height, but not disease status (CF or not) contributed to explaining variance. In line with this finding, no differences were found in muscle metabolism reflected by intracellular pH and the ratio of Pi/PCr at submaximal stages and peak exercise measured through MRI spectroscopy. Conclusions The lower absolute muscle power in patients with CF compared to controls is exclusively explained by the reduced muscle size in this study. No evidence was found for an intrinsic skeletal muscle dysfunction due to primary alterations of muscle metabolism.}, language = {en} } @article{LohrTerekhovWengetal.2019, author = {Lohr, David and Terekhov, Maxim and Weng, Andreas Max and Schroeder, Anja and Walles, Heike and Schreiber, Laura Maria}, title = {Spin echo based cardiac diffusion imaging at 7T: An ex vivo study of the porcine heart at 7T and 3T}, series = {PLoS ONE}, volume = {14}, journal = {PLoS ONE}, number = {3}, doi = {10.1371/journal.pone.0213994}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201376}, pages = {e0213994}, year = {2019}, abstract = {Purpose of this work was to assess feasibility of cardiac diffusion tensor imaging (cDTI) at 7 T in a set of healthy, unfixed, porcine hearts using various parallel imaging acceleration factors and to compare SNR and derived cDTI metrics to a reference measured at 3 T. Magnetic resonance imaging was performed on 7T and 3T whole body systems using a spin echo diffusion encoding sequence with echo planar imaging readout. Five reference (b = 0 s/mm\(^2\)) images and 30 diffusion directions (b = 700 s/mm\(^2\)) were acquired at both 7 T and 3 T using a GRAPPA acceleration factor R = 1. Scans at 7 T were repeated using R = 2, R = 3, and R = 4. SNR evaluation was based on 30 reference (b = 0 s/mm\(^2\)) images of 30 slices of the left ventricle and cardiac DTI metrics were compared within AHA segmentation. The number of hearts scanned at 7 T and 3 T was n = 11. No statistically significant differences were found for evaluated helix angle, secondary eigenvector angle, fractional anisotropy and apparent diffusion coefficient at the different field strengths, given sufficiently high SNR and geometrically undistorted images. R≥3 was needed to reduce susceptibility induced geometric distortions to an acceptable amount. On average SNR in myocardium of the left ventricle was increased from 29±3 to 44±6 in the reference image (b = 0 s/mm\(^2\)) when switching from 3 T to 7 T. Our study demonstrates that high resolution, ex vivo cDTI is feasible at 7 T using commercial hardware.}, language = {en} } @phdthesis{Baldauf2019, author = {Baldauf, Tobias}, title = {Radiologischer Routineultraschall bei Verdacht auf Appendizitis: Retrospektive Analyse der diagnostischen Wertigkeit}, doi = {10.25972/OPUS-19223}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-192231}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {Der allgemeinradiologische Ultraschall leistet einen wichtigen Beitrag in der Routinediagnostik der akuten Appendizitis bei Kindern und Erwachsenen. Die Zusammenschau aller verf{\"u}gbaren diagnostischen Befunde sollte zur Entscheidung f{\"u}r oder gegen eine Operation herangezogen werden. Die sonographische Untersuchung kann dazu beitragen, die Negativ Appendektomierate zu senken.}, language = {de} } @article{GeigerHirtlerGottfriedetal.2017, author = {Geiger, Julia and Hirtler, Daniel and Gottfried, Kristina and Rahman, Ozair and Bollache, Emilie and Barker, Alex J. and Markl, Michael and Stiller, Brigitte}, title = {Longitudinal Evaluation of Aortic Hemodynamics in Marfan Syndrome: New Insights from a 4D Flow Cardiovascular Magnetic Resonance Multi-Year Follow-Up Study}, series = {Journal of Cardiovascular Magnetic Resonance}, volume = {19}, journal = {Journal of Cardiovascular Magnetic Resonance}, number = {33}, doi = {10.1186/s12968-017-0347-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-171119}, year = {2017}, abstract = {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.}, language = {en} } @phdthesis{Baerwolff2019, author = {B{\"a}rwolff, Jennifer}, title = {Prognostische Marker im MRT bei diffus intrinsischen Ponsgliomen im Kindesalter}, doi = {10.25972/OPUS-18550}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-185505}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {Das DIPG ist eine f{\"u}r 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 {\"U}berlebenszeiten zeigen und somit als prognostische Marker genutzt werden k{\"o}nnen. Die Daten der 253 Studienteilnehmer mit neudiagnostizierten DIPG stammen aus der HIT-HGG-2007-Studie, sowie den 4 Vorg{\"a}ngerstudien HIT-GBM-A-D {\"u}ber 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 {\"U}berlebenswahrscheinlichkeiten f{\"u}r das OS und EFS bestimmt, sowie anschließendem Gruppenvergleich im Log- Rank-Test. Als prognostisch g{\"u}nstig erwiesen sich ein Erkrankungsalter bei Diagnosestellung unter 3 Jahren, sowie eine Therapie nach SKK-Schema. Auch eine fehlende Kontrastmittelaufnahme bei Diagnosestellung und eine große Tumorfl{\"a}che zeigten bessere {\"U}berlebenszeiten. Dagegen hatten weder das Geschlecht, noch die Histologie, noch eine max. Fl{\"a}chen- oder Volumenreduktion Einfluss auf die {\"U}berlebenszeiten der betroffenen Kinder.}, subject = {DIPG}, language = {de} } @article{NeufangAkhrifHerrmannetal.2016, author = {Neufang, S. and Akhrif, A. and Herrmann, C.G. and Drepper, C. and Homola, G.A. and Nowak, J. and Waider, J. and Schmitt, A.G. and Lesch, K.-P. and Romanos, M.}, title = {Serotonergic modulation of 'waiting impulsivity' is mediated by the impulsivity phenotype in humans}, series = {Translational Psychiatry}, journal = {Translational Psychiatry}, number = {6}, doi = {10.1038/tp.2016.210}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-164418}, pages = {e940}, year = {2016}, abstract = {In rodents, the five-choice serial reaction time task (5-CSRTT) has been established as a reliable measure of waiting impulsivity being defined as the ability to regulate a response in anticipation of reinforcement. Key brain structures are the nucleus accumbens (NAcc) and prefrontal regions (for example, pre- and infralimbic cortex), which are, together with other transmitters, modulated by serotonin. In this functional magnetic resonance imaging study, we examined 103 healthy males while performing the 5-CSRTT measuring brain activation in humans by means of a paradigm that has been widely applied in rodents. Subjects were genotyped for the tryptophan hydroxylase-2 (TPH2; G-703T; rs4570625) variant, an enzyme specific for brain serotonin synthesis. We addressed neural activation patterns of waiting impulsivity and the interaction between the NAcc and the ventromedial prefrontal cortex (vmPFC) using dynamic causal modeling. Genetic influence was examined via interaction analyses between the TPH2 genotype (GG homozygotes vs T allele carriers) and the degree of impulsivity as measured by the 5-CSRTT. We found that the driving input of the vmPFC was reduced in highly impulsive T allele carriers (reflecting a reduced top-down control) in combination with an enhanced response in the NAcc after correct target processing (reflecting an augmented response to monetary reward). Taken together, we found a high overlap of our findings with reports from animal studies in regard to the underlying cognitive processes, the brain regions associated with waiting impulsivity and the neural interplay between the NAcc and vmPFC. Therefore, we conclude that the 5-CSRTT is a promising tool for translational studies.}, language = {en} } @phdthesis{Gubik2019, author = {Gubik, Sebastian}, title = {Quantifizierung der Myokardperfusion mittels Dual Saturation Time Perfusion Imaging}, doi = {10.25972/OPUS-17830}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-178304}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {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.}, subject = {Myokardperfusion}, language = {de} } @phdthesis{Schmid2019, author = {Schmid, Gordian Georg}, title = {T1-Mapping zur fr{\"u}hen Detektion fibrotischer Ver{\"a}nderungen bei Anderson-Fabry-Patienten}, doi = {10.25972/OPUS-17760}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-177601}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2019}, abstract = {Bei Patienten mit Morbus Fabry spielt die kardiale MRT eine wesentliche Rolle f{\"u}r die Diagnostik, die Prognose und das Therapiemonitoring. Als Verfahren der Wahl zur Beurteilung einer fokalen myokardialen Fibrose hat sich das Late Gadolinium Enhancement (LGE) etabliert. Eine diffuse myokardiale Fibrosierung kann mittels LGE-Technik nicht suffizient abgebildet werden, da keine ausreichenden Unterschiede in der Signalintensit{\"a}t bestehen. Daher k{\"o}nnte das sog. post-KM T1-Mapping eine interessante Alternative sein. Bei diesem Verfahren lassen die T1-Relaxationszeiten R{\"u}ckschl{\"u}sse auf diffuse fibrotische Ver{\"a}nderungen des Myokards zu. In der vorliegenden Arbeit wurden 43 Fabry-Patienten (20 LGE-positiv und 23 LGE-negativ) im MRT untersucht. Hierzu wurde eine modifizierte Look-Locker Inversion-Recovery (MOLLI)-Sequenz zur Messung der T1-Maps verwendet. Ziel war es, durch das T1-Mapping Risikopatienten (u.a. LGE-negative Patienten) fr{\"u}her als bisher zu identifizieren und damit zeitnah einer entsprechenden Therapie zuzuf{\"u}hren. Die Ergebnisse zeigten, dass LGE-positive Fabry-Patienten eine fortgeschrittenere diffuse Myokardfibrose im visuell gesunden Myokard aufweisen als LGE-negative Patienten. Eine Unterscheidung anhand der T1-Zeiten zwischen LGE-negativen Patienten und gesunden Probanden war nicht m{\"o}glich. Somit kann das T1-Mapping nicht als diagnostische Methode zur Fr{\"u}herkennung einer diffusen Myokardfibrose bei Fabry-Patienten eingesetzt werden. Des Weiteren konnte gezeigt werden, dass die T1-Zeit im linksventrikul{\"a}ren Myokard bei Fabry-Patienten mit eingeschr{\"a}nkter Nierenfunktion k{\"u}rzer war als bei Patienten mit normaler Nierenfunktion, unabh{\"a}ngig vom Vorliegen einer fokalen Fibrose. Hingegen konnte im linksventrikul{\"a}ren Blut bei abnehmender glomerul{\"a}rer Filtrationsrate (GFR) keine k{\"u}rzere T1-Zeit festgestellt werden als bei normaler GFR. Außerdem waren die T1-Relaxationszeiten bei LGE-negativen, weiblichen Fabry-Patienten k{\"u}rzer als bei m{\"a}nnlichen Patienten ohne LGE. Eine abschließende Erkl{\"a}rung konnte hierf{\"u}r nicht gefunden werden. T1-Mapping wird bislang noch nicht in der Routinediagnostik bei Morbus Fabry eingesetzt. Allerdings steigt dessen Bedeutung im Rahmen von Studien. Weitere Forschungsbem{\"u}hungen sind notwendig, um geeignete Referenzwerte festzulegen und den Einfluss weiterer Faktoren auf die Fibrosierung des Myokards besser einsch{\"a}tzen zu k{\"o}nnen.}, subject = {Fabry-Krankheit}, language = {de} } @article{GilbertSchneemannScholzetal.2018, author = {Gilbert, F. and Schneemann, C. and Scholz, C. J. and Kickuth, R. and Meffert, R. H. and Wildenauer, R. and Lorenz, U. and Kellersmann, R. and Busch, A.}, title = {Clinical implications of fracture-associated vascular damage in extremity and pelvic trauma}, series = {BMC Muscuskeletal Disorders}, volume = {19}, journal = {BMC Muscuskeletal Disorders}, number = {404}, doi = {10.1186/s12891-018-2333-y}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176252}, year = {2018}, abstract = {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.}, language = {en} } @article{GilbertMeffertSchmalzletal.2018, author = {Gilbert, F. and Meffert, R. H. and Schmalzl, J. and Weng, A. M. and K{\"o}stler, H. and Eden, L.}, title = {Grade of retraction and tendon thickness correlates with MR-spectroscopically measured amount of fatty degeneration in full thickness supraspinatus tears}, series = {BMC Musculoskeletal Disorders}, volume = {19}, journal = {BMC Musculoskeletal Disorders}, number = {197}, doi = {10.1186/s12891-018-2096-5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176116}, year = {2018}, abstract = {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.}, language = {en} }