TY - JOUR A1 - Topsakal, Vedat A1 - Agrawal, Sumit A1 - Atlas, Marcus A1 - Baumgartner, Wolf-Dieter A1 - Brown, Kevin A1 - Bruce, Iain A. A1 - Dazert, Stefan A1 - Hagen, Rudolf A1 - Lassaletta, Luis A1 - Mlynski, Robert A1 - Raine, Christopher H. A1 - Rajan, Gunesh P. A1 - Schmutzhard, Joachim A1 - Sprinzl, Georg Mathias A1 - Staecker, Hinrich A1 - Usami, Shin-ichi A1 - Van Rompaey, Vincent A1 - Zernotti, Mario A1 - Heyning, Paul van de T1 - Minimally traumatic cochlear implant surgery: expert opinion in 2010 and 2020 JF - Journal of Personalized Medicine N2 - This study aimed to discover expert opinion on the surgical techniques and materials most likely to achieve maximum postoperative residual hearing preservation in cochlear implant (CI) surgery and to determine how these opinions have changed since 2010. A previously published questionnaire used in a study published in 2010 was adapted and expanded. The questionnaire was distributed to an international group of experienced CI surgeons. Present results were compared, via descriptive statistics, to those from the 2010 survey. Eighteen surgeons completed the questionnaire. Respondents clearly favored the following: round window insertion, slow array insertion, and the peri- and postoperative use of systematic antibiotics. Insertion depth was regarded as important, and electrode arrays less likely to induce trauma were preferred. The usefulness of dedicated soft-surgery training was also recognized. A lack of agreement was found on whether the middle ear cavity should be flushed with a non-aminoglycoside antibiotic solution or whether a sheath or insertion tube should be used to avoid contaminating the array with blood or bone dust. In conclusion, this paper demonstrates how beliefs about CI soft surgery have changed since 2010 and shows areas of current consensus and disagreement. KW - electric acoustic stimulation (EAS) KW - cochlear implants KW - atraumatic surgery KW - hearing preservation KW - partial deafness treatment Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-288196 SN - 2075-4426 VL - 12 IS - 10 ER - TY - JOUR A1 - Tecle, Nyat-Eyob A1 - Hackenberg, Stephan A1 - Scheich, Matthias A1 - Scherzad, Agmal A1 - Hagen, Rudolf A1 - Gehrke, Thomas T1 - Surgical management of lateral neck abscesses in children: a retrospective analysis of 100 cases JF - European Journal of Pediatrics N2 - Cervical abscesses are relatively common infections in pediatric patients. There is an ongoing debate about the necessity and time point of surgical drainage. The identification of a focus of infection might play an important role in facilitating a therapeutic decision. In a retrospective study, 100 pediatric patients aged 1–18 years who underwent incision and drainage of a lateral cervical abscess at our institution were analyzed. Patients were divided into two groups based on whether a focus of infection could be identified or not. Data collection included patient characteristics, microbiological results, antibiotic regimen, and clinical course. A focus of infection was found in 29% (29/100) of the patients, most frequently in the tonsils. A causative microorganism was found in 75% (75/100) of all patients, with Staphylococcus aureus and Streptococcus pyogenes being the most common pathogens. All patients received an empiric antibiotic therapy in addition to surgery. Antibiotic medication was changed in 31% in both groups (9/29 with a focus of infection and 22/71 without a focus of infection) during therapy. Children without an identified focus of infection generally were younger and had more comorbidities reducing immune response while also showing differences in the pathogens involved. There were no complications associated to surgery or antibiotic therapy in any of the patients involved. Conclusion: Children with an identified focus of infection show several differences compared to those with isolated lateral abscesses, especially regarding the microorganisms involved. But the focus of infection seems not to have an impact on patient’s outcome. What is Known: • Neck abscesses are a relatively common disease in the pediatric population and may cause serious complications. • Therapy in general consists of intravenous antibiotics with or without surgery. What is New: • The focus identification has no impact on patient’s outcome. • Children with an identified focus of infection show several differences compared to those with isolated lateral abscesses, especially regarding their medical history, age, and the microorganisms involved. KW - lateral neck abscesses KW - children KW - focus of infection KW - surgery Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324179 VL - 182 IS - 1 ER - TY - JOUR A1 - Hackenberg, Stephan A1 - Meyer, Till Jasper A1 - Häfner, Johannes A1 - Scheich, Matthias A1 - Stöth, Manuel A1 - Al-Tinawi, Fadi A1 - Neun, Tilmann A1 - Mlynski, Robert A1 - Hagen, Rudolf A1 - Scherzad, Agmal T1 - Surgical management of tympanojugular paragangliomas using the flexible CO\(_2\) laser JF - European Archives of Oto-Rhino-Laryngology N2 - Purpose Surgery is a standard therapy for tympanojugular paragangliomas (TJP). Maintaining the quality of life (QoL) requires functional preservation. The flexible CO\(_2\) laser allows contact-free tumor removal. This retrospective study compares the postoperative functional outcomes of TJP surgery with and without the flexible CO\(_2\) laser. Methods Between 2005 and 2019, 51 patients with TJP were surgically treated at a tertiary hospital. Until 2012, 17 patients received conventional surgery. Thereafter, the flexible laser was used in 34 patients. Tumor extend, pre- and postoperative cranial nerve function, and complications were compared between the groups. Results The cohort consisted of 33 class A and B tumors and 18 class C and D tumors. Preoperative embolization was performed in 17 cases. Class C/D TJP were usually removed via an infratemporal fossa type A approach. Gross total tumor removal was achieved in 14/18 class C/D tumors. 3/51 patients suffered from long-term partial or complete facial palsy. No differences in post-therapeutic cranial nerve function or complications were noted between the conventional and laser group. One recurrence was observed after complete tumor resection. Conclusion The flexible CO\(_2\) laser was shown to be a safe and effective alternative to conventional bipolar cauterization, which is appreciated by the surgeon in these highly vascularized tumors. Both techniques allowed a high tumor control rate and good long-term results also from a functional point of view. KW - tympanojugular paraganglioma KW - tympanic paraganglioma KW - jugular paraganglioma KW - surgical management of paraganglioma KW - laser surgery KW - flexible CO2 laser Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324164 VL - 279 IS - 12 ER - TY - THES A1 - Ilgen, Lukas T1 - Ermittlung cochleärer Längen- und Winkelmaße mittels Flachdetektor-Volumen-Computertomographie - Evaluation der Anwendung sekundärer Rekonstruktionen T1 - Analysis of the cochlear duct and angular length by flat-panel volume computed tomography - Evaluation of the use of secondary reconstructions N2 - Für die Cochlea-Implantat-Versorgung ist die Kenntnis der individuellen Anatomie der Hörschnecke im perioperativen Kontext essenziell, um ein suffizientes audiologisches Resultat sicherzustellen. Ein akkurates Verfahren hierfür stellt die 3D multiplanare Rekonstruktion (3D-curved MPR) in Schnittbildgebung dar. Notwendige Voraussetzung ist jedoch eine hinreichende Bildqualität. In dieser Arbeit wurde das Augenmerk auf die sekundäre Rekonstruktion von Primärdatensätzen der Flachdetektor-Volumen-Computertomographie (fpVCTSECO) gerichtet. Diese bietet nämlich die Möglichkeit, die Bildqualität zu steigern, ohne jedoch eine als kritisch einzuschätzende Dosissteigerung in Kauf nehmen zu müssen. Es konnte gezeigt werden, dass es für die Messung der Länge von 2 Schneckenwindungen (2TL), der gesamten cochleären Länge (CDL) und dem Winkelmaß (AL) mittels 3D-curved MPR in der fpVCT keinen signifikanten Unterschied gegenüber der Mehrschicht-CT gibt. In beiden Modalitäten wurden alle drei Parameter gegenüber der Referenzbildgebung micro-CT deutlich unterschätzt. Durch die fpVCTSECO war es möglich, die Genauigkeit der Messungen zu steigern und den Werten der Referenz anzunähern. Lediglich für AL muss eine geringfügige systematische Unterschätzung beachtet werden. Postoperativ zeigte sich mit einliegendem Elektrodenträger für 2TL eine ebenso präzise Messung wie präoperativ ohne. Jedoch wurde die CDL um circa 0,5 - 0,7 mm unterschätzt. Ursächlich hierfür dürften vor allem Metallartefakte gewesen sein. Auch wenn die 3D-curved MPR in Kombination mit der fpVCTSECO postoperativ zur Visualisierung der räumlichen Beziehung von Elektrodenträger, Modiolus und ossärer lateraler Wand sehr gut geeignet war, so muss sich der Einfluss dieser Diskrepanz für die audiologische Anpassung in Zukunft erst noch zeigen. N2 - Knowledge of the individual anatomy of the cochlea is essential for optimal hearing perception outcomes in cochlear implantation. 3D-curved multiplanar reconstruction (3D-curved MPR) in cross-sectional imaging is a very precise method. But for this purpose, high-resolution quality is an indispensable requirement. In this study, special attention was turned to secondary reconstruction of primary data of flat-panel volume computed tomography (fpVCTSECO). This postprocessing application provides an opportunity to increase image quality. Beneficially, there is no need of applying additional radiation dose, which should always be regarded critically. For the cochlear duct length (CDL), the two-turn length (2TL) and the angular length (AL), there were no statistically significant differences between fpVCT and multislice computed tomography applying 3D-curved MPR. In contrast to reference imaging modality micro-CT, a clinically relevant underestimation of all three parameters was evident. Using fpVCTSECO, precision of measurements could be increased significantly. It was possible to reach the accuracy of the reference. Only concerning AL, a slight and systematic underestimation must be considered. Postoperatively, after insertion of the electrode into the cochlea, measurement of 2TL was as precise as the preoperative one. For CDL, an underestimation of approximately 0.5 - 0.7 mm was evident. Most likely, this fact was linked to postoperative metal artifacts. Even though 3D-curved MPR in combination with fpVCTSECO is a great possibility to visualize the spatial relation of electrode, modiolus and bony lateral wall, the influence of this difference on audiological fitting procedures has still to be investigated in future studies. KW - Cochlea KW - Anatomie KW - Computertomografie KW - Cochlear-Implantat KW - Dreidimensionale Rekonstruktion KW - cochlear duct length KW - CDL KW - MSCT KW - fpVCT KW - CI Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-327945 ER - TY - THES A1 - Noyalet, Laurent T1 - Untersuchung der "Vestibular aqueduct" Morphologie bei Patienten mit Hörminderung und Morbus Menière am Würzburger Patientenkollektiv T1 - Investigation of the "Vestibular aqueduct" Morphology in Patients with Hearing Loss and Meniere's Disease in the Wuerzburg Patient Collective N2 - Trotz langjähriger klinischer Erfahrung, vielen Untersuchungen und Studien, ist die korrekte Diagnosestellung eines Morbus Menière immer noch schwierig. Diagnostische Mittel sind vor allem eine ausführliche Anamnese, die ECOG, Tonaudiogramm und der Ausschluss anderer Innenohrerkrankungen. Betroffene erleiden häufig Schwindelanfälle, Tinnitus, Ohrdruck und verlieren an Hörvermögen. Der progressive Verlauf dieser Erkrankung lässt sich meist nur verlangsamen. Häufig startet die Therapie funktionserhaltend-medikamentös mit Betahistin und Antiemetika, im weiteren Verlauf sind meist operative Eingriffe wie die Saccotomie nötig. Dabei wird der Saccus endolymphaticus aufgesucht, geschlitzt und mittels Silikondreieck offengehalten, um damit eine Entlastung des endolymphatischen Systems zu schaffen. Zeigt sich nur wenig Besserung kann destruierend fortgefahren werden. Hierbei sind vor allem die Gentamycin-Therapie und die Neurektomie oder Labyrinthektomie Mittel der Wahl. Diese Untersuchung hatte das Ziel eine weitere diagnostische Methode zu finden, um die MM-Diagnose zu sichern und eine Prognose in Bezug auf die Therapie mittels Saccotomie zu liefern. Im Fokus stand hierbei der vestibuläre Aquädukt, welcher bereits in vielen Arbeiten auffällig in Form und Lage bei MM-Patienten gewesen war. Vor allem der Bezug des Aquäduktes zu den Bogengängen und dessen Länge wurden in der vorliegenden Studie genauer betrachtet. Dies geschah durch Messungen anhand von CT-Bildern. Der Winkel zwischen den Bogengängen und dem VA und die Länge des VA wurde gemessen und ausgewertet. Dies wurde zur Bestätigung der Methode, sowohl an menschlichen Felsenbeinpräparaten mit qualitativ unterschiedlichen CT-Aufnahmen als auch an Patienten durchgeführt. Dabei konnte man keine signifikanten Unterschiede innerhalb der verschiedenen CT-Aufnahmen der Felsenbeinpräparate feststellen. Mit Bestätigung der Reliabilität dieser Methode wurden dann Patienten untersucht. Dabei wurden zwei Gruppen gebildet, Nicht-MM- und MM-Patienten. Die Nicht-MM bestanden aus Patienten mit einem Akustikusneurinom der Gegenseite oder einem Cochlea-Implantat, welche keinen MM aufwiesen. Die MM-Patienten wurden alle mit einer Saccotomie behandelt und hatten damit einen gesicherten MM. Die Auswertung der Messergebnisse stellte dar, dass bei MM-Betroffenen die Länge mit durchschnittlich 7,9 mm im Vergleich mit Nicht-Betroffenen-VA (9,5 mm), signifikant reduziert war. Auch die Ergebnisse der Winkelmessung zeigte bei allen Bogengängen signifikante Unterschiede. Um die Ergebnisse der Winkelmessung besser zu kategorisieren, wurde der VA-Score erstellt. Dieser vereinigt die Ergebnisse der drei Bogengänge zu einem Wert von 1 bis 8. Auch hier erwiesen sich die MM-Patienten als auffällig, da sich diese im VA-Score 2 mit 44% häuften. Im Gegensatz dazu waren die Ergebnisse der nicht Erkrankten breiter verteilt. Zur weiteren Auswertung zählten außerdem die anamnestischen Daten und der Verlauf der Saccotomie. Dadurch konnte der Erfolg der Behandlung bestimmt und diese mit den Untersuchungen des VA des jeweiligen Patienten korreliert werden. Dabei stellte sich heraus, dass vor allem bei VA mit hohen Winkeln und sehr kurzen VA die Erfolgsquote geringer war. Damit könnte also ein Zusammenhang zwischen Form und Lage des VA und Therapie bestehen. Um dies sicher zu bestätigen, braucht es noch mehr Patienten und eine klinisch zugelassene Software, die diese Messungen durchführen kann. Hierbei ist vor allem eine gute Bildgebung des Innenohrs wichtig, um den VA optimal messen zu können. Um die Messungen schnell und zuverlässig durchführen zu können, wäre eine Software, welche die Messungen automatisch durchführen kann, ein möglicher Ansatz. Die ausführliche Voruntersuchung wird jedoch weiterhin notwendig sein, um MM sicher zu diagnostizieren. N2 - Despite many years of clinical experience, many examinations and studies, the correct diagnosis of Meniere's disease is still difficult. Diagnostic tools are mainly a detailed medical history, the ECOG, tonal audiogram and the exclusion of other inner ear diseases. Affected individuals frequently experience vertigo, tinnitus, ear pressure, and loss of hearing. The progressive course of this disease can usually only be slowed down. Frequently, therapy starts with function-preserving drugs such as betahistine and antiemetics; in the further course, surgical interventions such as saccotomy are usually necessary. In this procedure, the saccus endolymphaticus is located, slit and held open by means of a silicone triangle in order to relieve the endolymphatic system. If there is only little improvement, destructive procedures can be continued. Gentamycin therapy and neurectomy or labyrinthectomy are the main methods of choice. The aim of this study was to find another diagnostic method to confirm the diagnosis of MD and to provide a prognosis regarding the therapy by saccotomy. The focus was on the vestibular aqueduct, which had already been shown in many studies to be conspicuous in shape and position in MD patients. Especially the relation of the aqueduct to the semicircular canals and its length were investigated in the present study. This was done by measurements based on CT images. The angle between the semicircular canals and the VA and the length of the VA were measured and evaluated. This was done to confirm the method, both on human petrous bone specimens with qualitatively different CT images and on patients. No significant differences were found within the different CT images of the petrous bone preparations. With confirmation of the reliability of this method, patients were then studied. Two groups were formed, non-MD and MD patients. The non-MM consisted of patients with an acoustic neuroma of the opposite side or a cochlear implant who did not have MD. The MD patients were all treated with saccotomy and thus had confirmed MD. The evaluation of the measurement results showed that the length was significantly reduced in MD patients with an average of 7.9 mm compared to non-affected VA (9.5 mm). The results of angle measurement also showed significant differences in all semicircular canals. To better categorize the results of the angle measurement, the VA score was created. This combines the results of the three semicircular canals into a score of 1 to 8. Again, the MD patients proved to be conspicuous, as they clustered in VA score 2 with 44%. In contrast, the results of the non-sufferers were more widely distributed. Further evaluation also included the anamnestic data and the outcome of the saccotomy. This made it possible to determine the success of the treatment and to correlate this with the examinations of the VA of the respective patient. It was found that especially VA with high angles and very short VA had a lower success rate. Thus, there could be a correlation between the shape and position of the VA and therapy. To confirm this for sure, more patients and clinically approved software that can perform these measurements are needed. Here, good imaging of the inner ear is especially important to be able to measure the VA optimally. To be able to perform the measurements quickly and reliably, software that can perform the measurements automatically would be a possible approach. However, the detailed preliminary examination will still be necessary to diagnose MD with certainty. KW - Menière-Krankheit KW - Morbus Menière KW - Schwindel KW - Innenohrkrankheit KW - vestibulärer Aquädukt KW - vestibular aqueduct KW - Saccotomie KW - Saccotomy KW - Vestibulärer-Aquädukt-Score Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-329423 ER - TY - JOUR A1 - Stefanakis, Mona A1 - Bassler, Miriam C. A1 - Walczuch, Tobias R. A1 - Gerhard-Hartmann, Elena A1 - Youssef, Almoatazbellah A1 - Scherzad, Agmal A1 - Stöth, Manuel Bernd A1 - Ostertag, Edwin A1 - Hagen, Rudolf A1 - Steinke, Maria R. A1 - Hackenberg, Stephan A1 - Brecht, Marc A1 - Meyer, Till Jasper T1 - The impact of tissue preparation on salivary gland tumors investigated by Fourier-transform infrared microspectroscopy JF - Journal of Clinical Medicine N2 - Due to the wide variety of benign and malignant salivary gland tumors, classification and malignant behavior determination based on histomorphological criteria can be difficult and sometimes impossible. Spectroscopical procedures can acquire molecular biological information without destroying the tissue within the measurement processes. Since several tissue preparation procedures exist, our study investigated the impact of these preparations on the chemical composition of healthy and tumorous salivary gland tissue by Fourier-transform infrared (FTIR) microspectroscopy. Sequential tissue cross-sections were prepared from native, formalin-fixed and formalin-fixed paraffin-embedded (FFPE) tissue and analyzed. The FFPE cross-sections were dewaxed and remeasured. By using principal component analysis (PCA) combined with a discriminant analysis (DA), robust models for the distinction of sample preparations were built individually for each parotid tissue type. As a result, the PCA-DA model evaluation showed a high similarity between native and formalin-fixed tissues based on their chemical composition. Thus, formalin-fixed tissues are highly representative of the native samples and facilitate a transfer from scientific laboratory analysis into the clinical routine due to their robust nature. Furthermore, the dewaxing of the cross-sections entails the loss of molecular information. Our study successfully demonstrated how FTIR microspectroscopy can be used as a powerful tool within existing clinical workflows. KW - formalin KW - fixation KW - tissue preparation KW - salivary gland neoplasia KW - FTIR spectroscopy KW - principal component analysis KW - discriminant analysis Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-304887 SN - 2077-0383 VL - 12 IS - 2 ER - TY - JOUR A1 - Friedrich, Maximilian U. A1 - Schneider, Erich A1 - Buerklein, Miriam A1 - Taeger, Johannes A1 - Hartig, Johannes A1 - Volkmann, Jens A1 - Peach, Robert A1 - Zeller, Daniel T1 - Smartphone video nystagmography using convolutional neural networks: ConVNG JF - Journal of Neurology N2 - Background Eye movement abnormalities are commonplace in neurological disorders. However, unaided eye movement assessments lack granularity. Although videooculography (VOG) improves diagnostic accuracy, resource intensiveness precludes its broad use. To bridge this care gap, we here validate a framework for smartphone video-based nystagmography capitalizing on recent computer vision advances. Methods A convolutional neural network was fine-tuned for pupil tracking using > 550 annotated frames: ConVNG. In a cross-sectional approach, slow-phase velocity of optokinetic nystagmus was calculated in 10 subjects using ConVNG and VOG. Equivalence of accuracy and precision was assessed using the “two one-sample t-test” (TOST) and Bayesian interval-null approaches. ConVNG was systematically compared to OpenFace and MediaPipe as computer vision (CV) benchmarks for gaze estimation. Results ConVNG tracking accuracy reached 9–15% of an average pupil diameter. In a fully independent clinical video dataset, ConVNG robustly detected pupil keypoints (median prediction confidence 0.85). SPV measurement accuracy was equivalent to VOG (TOST p < 0.017; Bayes factors (BF) > 24). ConVNG, but not MediaPipe, achieved equivalence to VOG in all SPV calculations. Median precision was 0.30°/s for ConVNG, 0.7°/s for MediaPipe and 0.12°/s for VOG. ConVNG precision was significantly higher than MediaPipe in vertical planes, but both algorithms’ precision was inferior to VOG. Conclusions ConVNG enables offline smartphone video nystagmography with an accuracy comparable to VOG and significantly higher precision than MediaPipe, a benchmark computer vision application for gaze estimation. This serves as a blueprint for highly accessible tools with potential to accelerate progress toward precise and personalized Medicine. KW - digital medicine KW - nystagmus KW - eye movement disorders KW - videooculography KW - computer vision KW - telemedicine KW - precision medicine Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324526 VL - 270 IS - 5 ER - TY - JOUR A1 - Sprinzl, Georg Mathias A1 - Magele, Astrid A1 - Schoerg, Philipp A1 - Hagen, Rudolf A1 - Rak, Kristen A1 - Kurz, Anja A1 - Van de Heyning, Paul A1 - Calvino, Miryam A1 - Lassaletta, Luis A1 - Gavilán, Javier T1 - A novel representation of audiological and subjective findings for acoustical, bone conduction and direct drive hearing solutions JF - Journal of Personalized Medicine N2 - Background: The benefit of hearing rehabilitation is often measured using audiological tests or subjective questionnaires/interviews. It is important to consider both aspects in order to evaluate the overall benefits. Currently, there is no standardized method for reporting combined audiological and patient reported subjective outcome measures in clinical practice. Therefore, this study focuses on showing the patient’s audiological, as well as subjective outcomes in one graph using data from an existing study. Method: The present paper illustrated a graph presenting data on four quadrants with audiological and subjective findings. These quadrants represented speech comprehension in quiet (unaided vs. aided) as WRS% at 65 dB SPL, speech recognition in noise (unaided vs. aided) as SRT dB SNR, sound field threshold (unaided vs. aided) as PTA\(_4\) in dB HL, wearing time and patient satisfaction questionnaire results. Results: As an example, the HEARRING graph in this paper represented audiological and subjective datasets on a single patient level or a cohort of patients for an active bone conduction hearing implant solution. The graph offered the option to follow the user’s performance in time. Conclusion: The HEARRING graph allowed representation of a combination of audiological measures with patient reported outcomes in one single graph, indicating the overall benefit of the intervention. In addition, the correlation and consistency between some results (e.g., aided threshold and aided WRS) can be better visualized. Those users who lacked performance benefits on one or more parameters and called for further insight could be visually identified. KW - bone conduction implant KW - hearing aids Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-311210 SN - 2075-4426 VL - 13 IS - 3 ER - TY - THES A1 - Bieniussa, Linda Ilse T1 - Different effects of conditional Knock-Out of Stat3 on the sensory epithelium of the Organ of Corti T1 - Unterschiedliche Auswirkungen des konditionellen Knock-Outs von Stat3 im sensorischen Epithel des Cortischen Organs N2 - Die Cochlea von Säugetieren nimmt Schall als Reaktion auf Vibrationen an frequenzabhängigen Positionen entlang des Cochlea-Kanals wahr. Die sensorischen äußeren Haarzellen, die von Stützzellen umgeben sind, wirken als Signalverstärker, indem sie ihre Zelllänge verändern können. Dies wird als Elektromotilität bezeichnet. Um eine korrekte elektrische Übertragung bei mechanischen Kräften zu gewährleisten, ist ein gewisser Widerstand des sensorischen Epithels eine Voraussetzung für die fehlerfreie Weiterleitung von Hörinformationen. Dieser Widerstand wird durch Mikrotubuli und deren posttranslationalen Modifikationen in den Stützzellen des sensorischen Epithels der Cochlea gewährleistet. Stat3 ist ein Transkriptionsfaktor, der an verschiedenen Phosphorylierungsstellen, sowie je nach Zelltyp und aktiviertem Signalweg an vielen zellulären Prozessen wie Differenzierung, Entzündung, Zellüberleben und Mikrotubuli-Dynamik beteiligt ist. Während Stat3 ein breites Spektrum an intrazellulären Funktionen hat, stellte sich die Frage, wie und ob Stat3 in den Zellen des Cortischen Organ einen Einfluss auf den Hörprozess hat. Um dies zu testen, wurde das Cre/loxp-System verwendet, um Stat3 in den äußeren Haarzellen oder den Stützzellen entweder vor oder nach Hörbeginn von Mäusen konditional auszuschalten. Um das Hörvermögen zu erfassen, wurden DPOAE- und ABR-Messungen durchgeführt, während molekulare und morphologische Untersuchungen mittels Sequenzierung und Immunhistochemie durchgeführt wurden. Eine konditioneller Knock-Out von Stat3 vor und nach dem Beginn des Hörens in äußeren Haarzellen führt zu leichten Hörschäden, während Synapsen, Nervenfasern und Mitochondrien nicht betroffen waren. Die Analyse der Sequenzierung von äußeren Haarzellen aus Mäusen mit konditionellem Knock-Out vor dem Beginn des Hörens ergab eine Störung der zellulären Homöostase und der extrazellulären Signale. Ein konditioneller Knock-Out von Stat3 in den äußeren Haarzellen nach Beginn des Hörens führte zu einem früh-entzündlichen Signalweg mit erhöhter Zytokinproduktion und der Hochregulierung des NF-κB-Wegs. In den Stützzellen führte ein kondioneller Knock-Out von Stat3 nur nach dem Beginn des Hörens zu einer Hörbeeinträchtigung. Synapsen, Nervensoma und -fasern waren jedoch von einem konditionellen Knock-Out von Stat3 in Stützzellen nicht betroffen. Dennoch war die detyronisierte Modifikation der Mikrotubuli verändert, was zu einer Instabilität der Stützzellen, insbesondere der Phalangealfortsätze, führte, was wiederum zu einer Instabilität des Epithels während des Hörvorgangs führte. Zusammenfassend lässt sich sagen, dass ein konditioneller Knock-Out von Stat3 in Zellen des Cortischen Organs zu einer Hörstörung führte. Während ein konditioneller Knock-Out in äußeren Haarzellen eine erhöhte Zytokinproduktion zur Folge hatte, verloren die Stützzellen ihre Zellstabilität aufgrund einer verminderten detyronisierten Modifikation der Mikrotubuli. Insgesamt deuten die Ergebnisse darauf hin, dass Stat3 ein wichtiges Protein für die Hörleistung ist. Es sind jedoch weitere Untersuchungen des molekularen Mechanismus erforderlich, um die Rolle von Stat3 in den Zellen des Corti-Organs zu verstehen. N2 - The mammalian cochlea detects sound in response to vibration at frequency-dependent positions along the cochlea duct. The sensory outer hair cells, which are surrounded by supporting cells, act as a signal amplifier by changing their cell length. This is called electromotility. To ensure correct electrical transmission during mechanical forces, a certain resistance of the sensory epithelium is a prerequisite for correct transduction of auditory information. This resistance is managed by microtubules and its posttranslational modification in the supporting cells of the sensory epithelium of the cochlea. Stat3 is a transcription factor, with its different phosphorylation sites, is involved in many cellular processes like differentiation, inflammation, cell survival and microtubule dynamics, depending on cell type and activated pathway. While Stat3 has a wide range of intracellular roles, the question arose, how and if Stat3 is involved in cells of the organ of Corti to ensure a correct hearing. To test this, Cre/loxp system were used to perform conditional Knock-Out (cKO) of Stat3 in outer hair cells or supporting cells either before hearing onset or after hearing onset. Hearing performances included DPOAE and ABR measurements, while molecular were performed by sequencing. Additionally, morphological examination was used by immunohistochemistry and electron microscopy. A cKO of Stat3 before and after hearing onset in outer hair cells leads to hearing impairments, whereas synapses, nerve fibers and mitochondria were not affected. Bulk sequencing analyzation of outer hair cells out of cKO mice before hearing onset resulted in a disturbance of cellular homeostasis and extracellular signals. A cKO of Stat3 in the outer hair cells after hearing onset resulted in inflammatory signaling pathway with increased cytokine production and upregulation of NF-kb pathway. In supporting cells, cKO of Stat3 only after hearing onset resulted in a hearing impairment. However, synapses, nerve soma and fibers were not affected of a cKO of Stat3 in supporting cells. Nevertheless, detyronisated modification of microtubules were altered, which can lead to an instability of supporting cells during hearing. In conclusion, Stat3 likely interact in a cell-specific and function-specific manner in cells of the organ of Corti. While a cKO in outer hair cells resulted in increased cytokine production, supporting cells altered its stability due to decreased detyronisated modification of microtubules. Together the results indicated that Stat3 is an important protein for hearing performances. However, additional investigations of the molecular mechanism are needed to understand the role of Stat3 in the cells of the organ of Corti. KW - Audiologie KW - Corti-Organ KW - Transgener Organismus KW - Sinneszelle KW - Elektrophysiologie KW - Stat3 KW - Mikrotubuli KW - conditional Knockout KW - hearing KW - Organ of Corti KW - Mikrotubulus Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-351434 ER - TY - THES A1 - Skornicka, Johannes T1 - Analyse des modulierenden Effekts von pegyliertem IGF-1 (pegIGF-1) auf die Hörfunktion von pmn-Mäusen T1 - Analysis of the modulating effect of pegylated IGF-1 (pegIGF-1) on the auditory function of pmn mice N2 - Die Maus mit progressiver motorischer Neuropathie (PMN) ist ein Modell für eine vererbte motorische Neuropathie mit progressiver Neurodegeneration. Die Degeneration der Axone geht mit homozygoten Mutationen des TBCE- Gens einher, das für das Tubulin-Chaperon-E- Protein kodiert. TBCE ist für die korrekte Dimerisierung von Alpha- und Beta-Tubulin verantwortlich. Auffallend ist, dass die PMN-Maus nach dem normalen Beginn des Hörens auch einen progressiven Hörverlust entwickelt, der durch die Degeneration des Hörnervs und den Verlust der äußeren Haarzellen (OHC) gekennzeichnet ist. Die Entwicklung dieser neuronalen und cochleären Pathologie ist Wirkung von peg-IGF-1 auf das auditorische System durch Behandlung ab dem 15. postnatalen Tag (p15). Die histologische Analyse ergab positive Auswirkungen auf die OHC-Synapsen der medialen olivocochleären (MOC) neuronalen Fasern und eine kurzfristige Abschwächung des OHC-Verlustes. Peg-IGF-1 war in der Lage, die Desorganisation der OHC-Synapsen bedingt wiederherzustellen und die Bereitstellung von cholinerger Acetyltransferase in den Präsynapsen aufrechtzuerhalten. Zur Beurteilung der auditorischen Funktion wurden frequenzspezifische Hirnstammreaktionen und otoakustische Emissionen mit Verzerrungsprodukten bei Tieren mit p21 und p28 aufgezeichnet. Trotz der positiven Auswirkungen auf die MOC-Fasern und die OHC konnte jedoch keine Wiederherstellung des Hörvermögens erreicht werden. Die vorliegende Arbeit zeigt, dass die synaptische Pathologie der efferenten MOC-Fasern in PMN-Mäusen eine besondere Form der "efferenten auditorischen Neuropathie" darstellt. Peg-IGF-1 zeigte eine otoprotektive Wirkung, indem es die Degeneration von OHCs und efferenten Synapsen verhinderte. Es sind jedoch verstärkte Anstrengungen zur Optimierung der Behandlung erforderlich, um nachweisbare Verbesserungen der Hörleistung zu erzielen. N2 - The progressive motor neuropathy (PMN) mouse is a model of an inherited motor neuropathy disease with progressive neurodegeneration. Axon degeneration associates with homozygous mutations of the TBCE gene encoding the tubulin chaperone E protein. TBCE is responsible for the correct dimerization of alpha and beta-tubulin. Strikingly, the PMN mouse also develops a progressive hearing loss after normal hearing onset, characterized by degeneration of the auditory nerve and outer hair cell (OHC) loss. However, the development of this neuronal and cochlear pathology is not fully understood yet. Previous studies with pegylated insulin-like growth factor 1 (peg-IGF-1) treatment in this mouse model have been shown to expand lifespan, weight, muscle strength, and motor coordination. Accordingly, peg-IGF-1 was evaluated for an otoprotective effect. We investigated the effect of peg-IGF-1 on the auditory system by treatment starting at postnatal day 15 (p15). Histological analysis revealed positive effects on OHC synapses of medial olivocochlear (MOC) neuronal fibers and a short-term attenuation of OHC loss. Peg-IGF-1 was able to conditionally restore the disorganization of OHC synapses and maintain the provision of cholinergic acetyltransferase in presynapses. To assess auditory function, frequency-specific auditory brainstem responses and distortion product otoacoustic emissions were recorded in animals on p21 and p28. However, despite the positive effect on MOC fibers and OHC, no restoration of hearing could be achieved. The present work demonstrates that the synaptic pathology of efferent MOC fibers in PMN mice represents a particular form of “efferent auditory neuropathy.” Peg-IGF-1 showed an otoprotective effect by preventing the degeneration of OHCs and efferent synapses. However, enhanced efforts are needed to optimize the treatment to obtain detectable improvements in hearing performances. KW - Cochlea KW - Mikrotubulus KW - Hörverlust KW - MOC-Fasern KW - pegylierter insulinähnlicher Wachstumsfaktor 1 KW - äußere Haarzelle KW - motorische Neuropathie Y1 - 2024 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-349125 ER - TY - JOUR A1 - Stebani, Jannik A1 - Blaimer, Martin A1 - Zabler, Simon A1 - Neun, Tilmann A1 - Pelt, Daniël M. A1 - Rak, Kristen T1 - Towards fully automated inner ear analysis with deep-learning-based joint segmentation and landmark detection framework JF - Scientific Reports N2 - Automated analysis of the inner ear anatomy in radiological data instead of time-consuming manual assessment is a worthwhile goal that could facilitate preoperative planning and clinical research. We propose a framework encompassing joint semantic segmentation of the inner ear and anatomical landmark detection of helicotrema, oval and round window. A fully automated pipeline with a single, dual-headed volumetric 3D U-Net was implemented, trained and evaluated using manually labeled in-house datasets from cadaveric specimen (N = 43) and clinical practice (N = 9). The model robustness was further evaluated on three independent open-source datasets (N = 23 + 7 + 17 scans) consisting of cadaveric specimen scans. For the in-house datasets, Dice scores of 0.97 and 0.94, intersection-over-union scores of 0.94 and 0.89 and average Hausdorf distances of 0.065 and 0.14 voxel units were achieved. The landmark localization task was performed automatically with an average localization error of 3.3 and 5.2 voxel units. A robust, albeit reduced performance could be attained for the catalogue of three open-source datasets. Results of the ablation studies with 43 mono-parametric variations of the basal architecture and training protocol provided task-optimal parameters for both categories. Ablation studies against single-task variants of the basal architecture showed a clear performance beneft of coupling landmark localization with segmentation and a dataset-dependent performance impact on segmentation ability. KW - anatomy KW - bone imaging KW - diagnosis KW - medical imaging KW - software KW - three-dimensional imaging KW - tomography Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357411 VL - 13 ER - TY - JOUR A1 - Engert, Jonas A1 - Spahn, Bjoern A1 - Bieniussa, Linda A1 - Hagen, Rudolf A1 - Rak, Kristen A1 - Voelker, Johannes T1 - Neurogenic stem cell niche in the auditory Thalamus: in vitro evidence of neural stem cells in the rat medial geniculate body JF - Life N2 - The medial geniculate body (MGB) is a nucleus of the diencephalon representing a relevant segment of the auditory pathway and is part of the metathalamus. It receives afferent information via the inferior brachium of the inferior colliculus and transmits efferent fibers via acoustic radiations to the auditory cortex. Neural stem cells (NSCs) have been detected in certain areas along the auditory pathway. They are of great importance as the induction of an adult stem cell niche might open a regenerative approach to a causal treatment of hearing disorders. Up to now, the existence of NSCs in the MGB has not been determined. Therefore, this study investigated whether the MGB has a neural stem cell potential. For this purpose, cells were extracted from the MGB of PND 8 Sprague-Dawley rats and cultured in a free-floating cell culture assay, which showed mitotic activity and positive staining for stem cell and progenitor markers. In differentiation assays, the markers β-III-tubulin, GFAP, and MBP demonstrated the capacity of single cells to differentiate into neuronal and glial cells. In conclusion, cells from the MGB exhibited the cardinal features of NSCs: self-renewal, the formation of progenitor cells, and differentiation into all neuronal lineage cells. These findings may contribute to a better understanding of the development of the auditory pathway. KW - neurosphere KW - auditory pathway KW - neural stem cell potential Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-319387 SN - 2075-1729 VL - 13 IS - 5 ER - TY - JOUR A1 - Kuzkina, A. A1 - Rößle, J. A1 - Seger, A. A1 - Panzer, C. A1 - Kohl, A. A1 - Maltese, V. A1 - Musacchio, T. A1 - Blaschke, S. J. A1 - Tamgüney, G. A1 - Kaulitz, S. A1 - Rak, K. A1 - Scherzad, A. A1 - Zimmermann, P. H. A1 - Klussmann, J. P. A1 - Hackenberg, S. A1 - Volkmann, J. A1 - Sommer, C. A1 - Sommerauer, M. A1 - Doppler, K. T1 - Combining skin and olfactory α-synuclein seed amplification assays (SAA)—towards biomarker-driven phenotyping in synucleinopathies JF - npj Parkinson’s Disease N2 - Seed amplification assays (SAA) are becoming commonly used in synucleinopathies to detect α-synuclein aggregates. Studies in Parkinson’s disease (PD) and isolated REM-sleep behavior disorder (iRBD) have shown a considerably lower sensitivity in the olfactory epithelium than in CSF or skin. To get an insight into α-synuclein (α-syn) distribution within the nervous system and reasons for low sensitivity, we compared SAA assessment of nasal brushings and skin biopsies in PD (n = 27) and iRBD patients (n = 18) and unaffected controls (n = 30). α-syn misfolding was overall found less commonly in the olfactory epithelium than in the skin, which could be partially explained by the nasal brushing matrix exerting an inhibitory effect on aggregation. Importantly, the α-syn distribution was not uniform: there was a higher deposition of misfolded α-syn across all sampled tissues in the iRBD cohort compared to PD (supporting the notion of RBD as a marker of a more malignant subtype of synucleinopathy) and in a subgroup of PD patients, misfolded α-syn was detectable only in the olfactory epithelium, suggestive of the recently proposed brain-first PD subtype. Assaying α-syn of diverse origins, such as olfactory (part of the central nervous system) and skin (peripheral nervous system), could increase diagnostic accuracy and allow better stratification of patients. KW - diagnostic markers KW - Parkinson's disease Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-357687 SN - 2373-8057 VL - 9 ER - TY - JOUR A1 - Linz, Christian A1 - Brands, Roman C. A1 - Kertels, Olivia A1 - Dierks, Alexander A1 - Brumberg, Joachim A1 - Gerhard-Hartmann, Elena A1 - Hartmann, Stefan A1 - Schirbel, Andreas A1 - Serfling, Sebastian A1 - Zhi, Yingjun A1 - Buck, Andreas K. A1 - Kübler, Alexander A1 - Hohm, Julian A1 - Lapa, Constantin A1 - Kircher, Malte T1 - Targeting fibroblast activation protein in newly diagnosed squamous cell carcinoma of the oral cavity – initial experience and comparison to [\(^{18}\)F]FDG PET/CT and MRI JF - European Journal of Nuclear Medicine and Molecular Imaging N2 - Purpose While [\(^{18}\)F]-fluorodeoxyglucose ([\(^{18}\)F]FDG) is the standard for positron emission tomography/computed tomography (PET/CT) imaging of oral squamous cell carcinoma (OSCC), diagnostic specificity is hampered by uptake in inflammatory cells such as neutrophils or macrophages. Recently, molecular imaging probes targeting fibroblast activation protein α (FAP), which is overexpressed in a variety of cancer-associated fibroblasts, have become available and might constitute a feasible alternative to FDG PET/CT. Methods Ten consecutive, treatment-naïve patients (8 males, 2 females; mean age, 62 ± 9 years) with biopsy-proven OSCC underwent both whole-body [\(^{18}\)F]FDG and [\(^{68}\)Ga]FAPI-04 (FAP-directed) PET/CT for primary staging prior to tumor resection and cervical lymph node dissection. Detection of the primary tumor, as well as the presence and number of lymph node and distant metastases was analysed. Intensity of tracer accumulation was assessed by means of maximum (SUV\(_{max}\)) and peak (SUV\(_{peak}\) standardized uptake values. Histological work-up including immunohistochemical staining for FAP served as standard of reference. Results [\(^{18}\)F]FDG and FAP-directed PET/CT detected all primary tumors with a SUVmax of 25.5 ± 13.2 (FDG) and 20.5 ± 6.4 (FAP-directed) and a SUVpeak of 16.1 ± 10.3 ([\(^{18}\)F]FDG) and 13.8 ± 3.9 (FAP-directed), respectively. Regarding cervical lymph node metastases, FAP-directed PET/CT demonstrated comparable sensitivity (81.3% vs. 87.5%; P = 0.32) and specificity (93.3% vs. 81.3%; P = 0.16) to [\(^{18}\)F]FDG PET/CT. FAP expression on the cell surface of cancer-associated fibroblasts in both primary lesions as well as lymph nodes metastases was confirmed in all samples. Conclusion FAP-directed PET/CT in OSCC seems feasible. Future research to investigate its potential to improve patient staging is highly warranted. KW - molecular imaging KW - fibroblast activation protein KW - head and neck cancer KW - PET Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-307246 SN - 1619-7070 SN - 1619-7089 VL - 48 IS - 12 ER - TY - JOUR A1 - Bassler, Miriam C. A1 - Knoblich, Mona A1 - Gerhard-Hartmann, Elena A1 - Mukherjee, Ashutosh A1 - Youssef, Almoatazbellah A1 - Hagen, Rudolf A1 - Haug, Lukas A1 - Goncalves, Miguel A1 - Scherzad, Agmal A1 - Stöth, Manuel A1 - Ostertag, Edwin A1 - Steinke, Maria A1 - Brecht, Marc A1 - Hackenberg, Stephan A1 - Meyer, Till Jasper T1 - Differentiation of salivary gland and salivary gland tumor tissue via Raman imaging combined with multivariate data analysis JF - Diagnostics N2 - Salivary gland tumors (SGTs) are a relevant, highly diverse subgroup of head and neck tumors whose entity determination can be difficult. Confocal Raman imaging in combination with multivariate data analysis may possibly support their correct classification. For the analysis of the translational potential of Raman imaging in SGT determination, a multi-stage evaluation process is necessary. By measuring a sample set of Warthin tumor, pleomorphic adenoma and non-tumor salivary gland tissue, Raman data were obtained and a thorough Raman band analysis was performed. This evaluation revealed highly overlapping Raman patterns with only minor spectral differences. Consequently, a principal component analysis (PCA) was calculated and further combined with a discriminant analysis (DA) to enable the best possible distinction. The PCA-DA model was characterized by accuracy, sensitivity, selectivity and precision values above 90% and validated by predicting model-unknown Raman spectra, of which 93% were classified correctly. Thus, we state our PCA-DA to be suitable for parotid tumor and non-salivary salivary gland tissue discrimination and prediction. For evaluation of the translational potential, further validation steps are necessary. KW - salivary gland tumor KW - confocal Raman imaging KW - principal component analysis KW - discriminant analysis KW - multivariate data analysis KW - molecular diagnostics Y1 - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-355558 SN - 2075-4418 VL - 14 IS - 1 ER -