TY - THES A1 - Kretzer, Katharina T1 - Einfluss der Form elektrischer Impulse auf die intracochleäre neuronale Antwort bei Cochlea-Implantat-Trägern: triphasische Pulse mit anodischer und kathodischer zweiter Phase T1 - Influence of the shape of electrical pulses on the intracochlear neural response in cochlear implant recipients: triphasic pulses with anodic and cathodic second phase N2 - Vorliegende Arbeit beschäftigte sich mit der Verbesserung von Defiziten der elektrischen Stimulation durch Cochlea Implantate (CI) mit alternativen Pulsformen. Dabei wurde mit elektrophysiologischen und psychophysikalischen Methoden untersucht, wie sich die Pulsformen auf die Effektivität der Stimulation auswirken. Es wurden präzisions-triphasische Pulse (pTP) mit anodischer und kathodischer zweiter Phase anhand der Daten von elf Probanden untersucht. Im Rahmen der objektiven elektrophysiologischen Messung wurde mit den unterschiedlichen Formen des pTP an drei unterschiedlichen Kontaktpositionen auf den CI-Elektrodenträgern stimuliert, und die Stärke der jeweils evozierten neuronalen Antwort aufgezeichnet. Der subjektive psychophysikalische Test diente dazu, die pulsformspezifischen Hörschwellen zu bestimmen und wurde an zwei unterschiedlichen Kontakten auf den CI-Elektrodenträgern durchgeführt. Dabei erzielten pTP, welche eine symmetrisch-triphasische Pulsform aufwiesen, geringere neuronale Antwortstärken und höhere Hörschwellen als die pTP, die einer biphasischen Pulsform glichen. Diejenigen pTP, die biphasischen Pulsen mit anodischer erster Phase glichen, erzielten dabei die höchsten neuronalen Antwortstärken und die niedrigsten Hörschwellen. N2 - Present work dealt with the improvement of deficits of electrical stimulation by cochlear implants (CI) by means of alternative pulse shapes. This involved the use of electrophysiological und psychophysical methods to investigate the effect of pulse shape on the effectiveness of stimulation. Precision-triphasic pulses (pTP) with anodic and cathodic second phase were examined using data from eleven subjects. In the objective electrophysiological measurement, the different shapes of the pTP were stimulated from three different contact positions on the CI electrode arrays and the strength of the neural response evoked in each case was recorded. In the subjective psychophysical test, pTP stimulation was performed from two different contact positions on the CI electrode arrays and the pulse shape-specific detection thresholds were compared. The results showed that pTP, which exhibited a symmetric-triphasic pulse shape, achieved lower neuronal response strengths and higher detection thresholds than pTP that resembled a biphasic pulse shape. Those pTP, that resembled biphasic pulses with an anodic first phase, achieved the highest neuronal response strengths and the lowest detection thresholds. KW - Cochlear-Implantat KW - Elektrophysiologie KW - Psychophysik KW - elektrische Stimulation KW - cochlear implant KW - electrical stimulation KW - psychophysics KW - electrophysiology Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-281650 ER - TY - THES A1 - Derouet [geb. Schenkelberger], Freya Kwen-Kwes T1 - Entwicklung optimierter Ankopplungsbedingungen von aktiven Mittelohrimplantaten am runden Fenster T1 - Development of optimized coupling conditions of active middle ear implants at the round window N2 - Seit Mitte der 90er-Jahre gewinnen aktive Mittelohrimplantate wie die Vibrant sound bridge (VSB) zunehmend an Bedeutung. Sie können zur Rehabilitation von Schallleitungs- und Schallempfindungsstörungen, sowie kombinierter Hörstörungen indiziert sein. Die Vibrant sound bridge stellt eine Alternative für Patienten dar, bei denen aus verschiedenen Gründen eine Unverträglichkeit gegenüber herkömmlichen Hörgeräten besteht. Bei der Implantation des Floating mass transducers (FMT) am runden Fenster zeigte sich in der Klinik neben einer hohen Revisionsrate von bis zu 15,6 % eine hohe Varianz der audiologischen Ergebnisse, was auf eine unkontrollierte und mangelnde Ankopplung des Floating mass transducers an das runde Fenster zurückzuführen ist. Erste Ergebnisse der kontrollierten Ankopplung am runden Fenster mit einem Kamin zeigten vielversprechende Ergebnisse. Die suffiziente Fixation des Kamins an der Rundfensternische stellt eine Herausforderung dar. Es bedarf eines Haftvermittlers, der eine suffiziente Verbindung zwischen dem Titankamin und dem darunter befindlichen Knochen am runden Fenster herstellt. Ziel der Dissertation war die Findung einer geeigneten Haftkomponente zur Fixation des Kamins am runden Fenster. Es wurden der Calciumphosphatzement HydroSet® (Fa. Stryker) und der Glasionomerzement Ketac™ Cem (Fa. ESPE 3M™ Deutschland) untersucht. In Anlehnung an DIN 13990-2 wurden nach Einwirkung physikalischen Stresses in Form von Temperatur und Feuchtigkeit die Scherhaftfestigkeit der Titanzylinder an humanen Felsenbeinknochen gemessen. Es zeigte sich eine schwach signifikant bessere Haftung für das Calciumphosphatzement HydroSet®, bei insgesamt geringer Scherhaftfestigkeit beider Zemente im Vergleich mit anderen zahnheilkundlichen Adhäsiven der Literatur. N2 - Since the mid-1990s, active middle ear implants such as the Vibrant sound bridge (VSB) have become increasingly important. They may be indicated for the rehabilitation of conductive and sensorineural hearing disorders, as well as combined hearing disorders. The Vibrant sound bridge is an alternative for patients who are intolerant to conventional hearing aids for various reasons. Implantation of the Floating mass transducer (FMT) at the round window showed a high revision rate of up to 15.6% and a high variance of audiological results in the clinic, which can be attributed to an uncontrolled and insufficient coupling of the Floating mass transducer to the round window. Initial results of controlled coupling to the round window with a chimney showed promising results. Sufficient fixation of the cylinder ("chimney") to the round window is found to be a challenge. A bonding agent is needed to create a sufficient connection between the titanium cylinder ("chimney") and the underlying bone on the round window. The objective of this study was to find a suitable bonding component to fix the cylinder ("chimney") to the round window. The calcium phosphate cement HydroSet® (Stryker) and the glass ionomer cement Ketac™ Cem (ESPE 3M™ Germany) were investigated. In accordance with DIN 13990-2, the shear bond strength of the titanium cylinders was measured on human temporal bones after exposure to physical stress in the form of temperature and humidity. A weakly significant better adhesion was found for the calcium phosphate cement HydroSet®, with overall low shear bond strength of both cements in comparison with other dental adhesives in the literature. KW - Ankopplungsbedingungen KW - aktive Mittelohrimplantate KW - Rundfensterankopplung Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-278079 ER - TY - THES A1 - Wagner, Martin T1 - Zyto- und Gentoxizität von Zinkoxid-Nanopartikeln in humanen mesenchymalen Stammzellen nach repetitiver Exposition und im Langzeitversuch T1 - Time-Dependent Toxic and Genotoxic Effects of Zinc Oxide Nanoparticles after Long-Term and Repetitive Exposure to Human Mesenchymal Stem Cells N2 - Zinkoxid-Nanopartikel (ZnO-NP) finden in vielen Produkten des täglichen Verbrauchs Verwendung. Daten über die toxikologischen Eigenschaften von ZnO-NP werden kontrovers diskutiert. Die menschliche Haut ist in Bezug auf die ZnO-NP Exposition das wichtigste Kontakt-Organ. Intakte Haut stellt eine suffiziente Barriere gegenüber NP dar. Bei defekter Haut ist ein Kontakt zu den proliferierenden Stammzellen möglich, sodass diese als wichtiges toxikologische Ziel für NP darstellen. Das Ziel dieser Dissertation war die Bewertung der genotoxischen und zytotoxischen Effekte an humanen mesenchymalen Stammzellen (hMSC) durch niedrig dosierte ZnO-NP nach 24 stündiger Exposition, repetitiven Expositionen und im Langzeitversuch bis zu 6 Wochen. Zytotoxische Wirkungen von ZnO-NP wurden mit 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromid-Test (MTT) gemessen. Darüber hinaus wurde die Genotoxizität durch den Comet-Assay bewertet. Zur Langzeitbeobachtung bis zu 6 Wochen wurde die Transmissionselektronenmikroskopie (TEM) verwendet. Zytotoxizität nach 24-stündiger ZnO-NP-Exposition war ab einer Konzentration von 50 µg/ml nachweisbar. Genotoxizität konnten bereits bei Konzentrationen von 1 und 10 µg/ml ZnO-NP beschrieben werden. Wiederholte Exposition verstärkte die Zyto-, aber nicht die Genotoxizität. Eine intrazelluläre NP-Akkumulation mit Penetration der Zellorganelle wurde bei einer Exposition bis zu 6 Wochen beobachtet. Die Ergebnisse deuten auf zytotoxische und genotoxisches Effekte von ZnO-NP hin. Bereits geringe Dosen von ZnO-NP können bei wiederholter Exposition toxische Wirkungen hervorrufen sowie eine langfristige Zellakkumulation. Diese Daten sollten bei der Verwendung von ZnO-NP an geschädigter Haut berücksichtigt werden. N2 - Zinc oxide nanoparticles (ZnO-NP) are widely used in many products of daily consumption. Data on the toxicological properties of the ZnO-NP used are discussed controversially. Human skin is the most important organ in terms of ZnO-NP exposure. Intact skin has been shown to provide an adequate barrier against NPs, while defective skin allows NP contact with proliferating cells. Among proliferating cells, stem cells are the main toxicological target for NPs. Therefore, the aim of this dissertation was to evaluate the genotoxic and cytotoxic effects of human mesenchymal stem cells (hMSC) by low-dose ZnO-NP after 24 hours of exposure, repetitive exposures and in long-term experiments up to 6 weeks. Cytotoxic effects of ZnO-NP were measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test (MTT). In addition, genotoxicity was assessed by the comet assay. Transmission electron microscopy (TEM) was used for long-term observation after 6 exposure periods. The results of the study show that ZnO-NP has a cytotoxic effect starting at high concentrations of 50 µg/mL and could demonstrate genotoxic effects in hMSC exposed to 1 and 10 µg/ml ZnO-NP. Repeated exposure enhanced cytotoxicity but not genotoxicity. Intracellular NP accumulation with penetration of the cell organelles was observed at exposure up to 6 weeks. The results indicate the cytotoxic and genotoxic potential of ZnO-NP. Even small doses of ZnO-NP can cause toxic effects with repeated exposure and long-term cell accumulation. These data should be considered when using ZnO-NP on damaged skin. KW - nanoparticle KW - zinc oxid KW - stem cells KW - nanotoxicology KW - human skin KW - Nanopartikel KW - humane mesenchymale Stammzellen KW - Genotoxizität KW - Zytotoxizität KW - Repetitive Exposition KW - Elektronenmikroskopie Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-275726 ER - TY - JOUR A1 - Herrmann, David P. A1 - Müller-Graff, Franz-Tassilo A1 - Kaulitz, Stefan A1 - Cebulla, Mario A1 - Kurz, Anja A1 - Hagen, Rudolf A1 - Neun, Tilmann A1 - Rak, Kristen T1 - Application of intentional facial nerve stimulation during cochlear implantation as an electrophysiological tool to estimate the intracochlear electrode position JF - Scientific Reports N2 - This proof of concept describes the use of evoked electromyographic (EMG) activation of the facial nerve for intraoperative monitoring of the electrode insertion during cochlear implantation (CI). Intraoperative EMG measurements from the facial nerve were conducted in nine patients undergoing CI implantation. Electric current pulses were emitted from contacts on the CI array during and immediately after electrode insertion. For control, the results of EMG measurements were compared to postoperative flat panel volume computed tomography scans with secondary reconstruction (fpVCT\(_{SECO}\)). During insertion, the EMG response evoked by the electrical stimulation from the CI was growing with the stimulating contact approaching the facial nerve and declined with increasing distance. After full insertion, contacts on the apical half of the CI array stimulated higher EMG responses compared with those on the basal half. Comparison with postoperative imaging demonstrated that electrode contacts stimulating high EMG responses had the shortest distances to the facial nerve. It could be demonstrated that electrically evoked EMG activation of the facial nerve can be used to monitor the progress during CI electrode insertion and to control the intracochlear electrode position after full insertion. KW - facial nerve KW - electromyographic KW - cochlear implantation Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-300197 VL - 12 IS - 1 ER - TY - JOUR A1 - Bieniussa, Linda A1 - Kahraman, Baran A1 - Skornicka, Johannes A1 - Schulte, Annemarie A1 - Voelker, Johannes A1 - Jablonka, Sibylle A1 - Hagen, Rudolf A1 - Rak, Kristen T1 - Pegylated insulin-like growth factor 1 attenuates hair cell loss and promotes presynaptic maintenance of medial olivocochlear cholinergic fibers in the cochlea of the progressive motor neuropathy mouse JF - Frontiers in Neurology 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 - microtubules KW - MOC fibers KW - hearing loss KW - pegylated insulin-like growth factor 1 KW - outer hair cell (OHC) KW - motor neuropathy Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-276669 SN - 1664-2295 VL - 13 ER - TY - THES A1 - Engert, Jonas T1 - Untersuchung neuronaler Stammzellen des Colliculus inferior der Ratte im zeitlichen Verlauf T1 - Analysis of neural stem cells of the rat inferior colliculus in the course of time N2 - Neural stem cells (NSCs) have been recently identified in the inferior colliculus (IC). These cells are of particular interest, as no casual therapeutic options for impaired neural structures exist. This research project aims to evaluate the neurogenic potential in the rat IC from early postnatal days until adulthood. The IC of rats from postnatal day 6 up to 48 was examined by neurosphere assays and histological sections. In free-floating IC cell cultures, neurospheres formed from animals from early postnatal to adulthood. The amount of generated neurospheres decreased in older ages and increased with the number of cell line passages. Cells in the neurospheres and the histological sections stained positively with NSC markers (Doublecortin, Sox-2, Musashi-1, Nestin, and Atoh1). Dissociated single cells from the neurospheres differentiated and were stained positively for the neural lineage markers β-III-tubulin, glial fibrillary acidic protein, and myelin basic protein. In addition, NSC markers (Doublecortin, Sox-2, CDK5R1, and Ascl-1) were investigated by qRT-PCR. In conclusion, a neurogenic potential in the rat IC was detected and evaluated from early postnatal days until adulthood. The identification of NSCs in the rat IC and their age-specific characteristics contribute to a better understanding of the development and the plasticity of the auditory pathway and might be activated for therapeutic use. N2 - Neuronale Stammzellen wurden kürzlich im unteren Colliculus inferior (CI) identifiziert. Diese Zellen sind von besonderem Interesse, da es keine therapeutischen Optionen für geschädigte neuronale Strukturen gibt. Ziel dieses Forschungsprojekts ist es, das neurogene Potenzial im CI der Ratte von den ersten postnatalen Tagen bis zum Erwachsenenalter zu untersuchen. Der CI von Ratten vom 6. bis zum 48. postnatalen Tag wurde mit Neurosphären-Assays und histologischen Schnitten untersucht. In frei schwimmenden CI-Zellkulturen bildeten sich Neurosphären bei Tieren vom frühen postnatalen Alter bis zum Erwachsenenalter. Die Menge der gebildeten Neurosphären nahm im höheren Alter ab und stieg mit der Anzahl der Zelllinienpassagen. Die Zellen in den Neurosphären und die histologischen Schnitte zeigten eine positive Färbung mit neuronalen Stammzell-Markern (Doublecortin, Sox-2, Musashi-1, Nestin und Atoh1). Dissoziierte Einzelzellen aus den Neurosphären differenzierten und wurden positiv für die neuralen Abstammungsmarker β-III-Tubulin, GFAP und MBP angefärbt. Darüber hinaus wurden neuronalen Stammzell-Marker (Doublecortin, Sox-2, CDK5R1 und Ascl-1) mittels qRT-PCR untersucht. Zusammenfassend lässt sich sagen, dass ein neurogenes Potenzial im CI der Ratte von den frühen postnatalen Tagen bis zum Erwachsenenalter nachgewiesen und bewertet wurde. Die Identifizierung von neuronalen Stammzellen im CI der Ratte und ihre altersspezifischen Merkmale tragen zu einem besseren Verständnis der Entwicklung und der Plastizität der Hörbahn bei und könnten für eine therapeutische Nutzung aktiviert werden. KW - Colliculus inferior KW - Neurogenesis KW - Stem cells KW - Neuronale Stammzellen KW - Neural Stem cells KW - Colliculus inferior KW - Adulte Neurogenese KW - Hörbahn KW - Inferior colliculus KW - adult neurogenesis KW - auditory pathway Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-282642 ER - TY - JOUR A1 - Noyalet, Laurent A1 - Ilgen, Lukas A1 - Bürklein, Miriam A1 - Shehata-Dieler, Wafaa A1 - Taeger, Johannes A1 - Hagen, Rudolf A1 - Neun, Tilmann A1 - Zabler, Simon A1 - Althoff, Daniel A1 - Rak, Kristen T1 - Vestibular aqueduct morphology and Meniere’s disease - development of the vestibular aqueduct score by 3D analysis JF - Frontiers in Surgery N2 - Improved radiological examinations with newly developed 3D models may increase understanding of Meniere's disease (MD). The morphology and course of the vestibular aqueduct (VA) in the temporal bone might be related to the severity of MD. The presented study explored, if the VA of MD and non-MD patients can be grouped relative to its angle to the semicircular canals (SCC) and length using a 3D model. Scans of temporal bone specimens (TBS) were performed using micro-CT and micro flat panel volume computed tomography (mfpVCT). Furthermore, scans were carried out in patients and TBS by computed tomography (CT). The angle between the VA and the three SCC, as well as the length of the VA were measured. From these data, a 3D model was constructed to develop the vestibular aqueduct score (VAS). Using different imaging modalities it was demonstrated that angle measurements of the VA are reliable and can be effectively used for detailed diagnostic investigation. To test the clinical relevance, the VAS was applied on MD and on non-MD patients. Length and angle values from MD patients differed from non-MD patients. In MD patients, significantly higher numbers of VAs could be assigned to a distinct group of the VAS. In addition, it was tested, whether the outcome of a treatment option for MD can be correlated to the VAS. KW - vestibular aqueduct (VA) KW - 3D analysis KW - temporal bone KW - saccotomy KW - computed tomography KW - Meniere’s disease Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-312893 SN - 2296-875X VL - 9 ER - TY - JOUR A1 - Gehrke, Thomas A1 - Scherzad, Agmal A1 - Hagen, Rudolf A1 - Hackenberg, Stephan T1 - Deep neck infections with and without mediastinal involvement: treatment and outcome in 218 patients JF - European Archives of Oto-Rhino-Laryngology N2 - Purpose Infections of the deep neck, although becoming scarcer due to the widespread use of antibiotics, still represent a dangerous and possibly deadly disease, especially when descending into the mediastinum. Due to the different specialities involved in the treatment and the heterogenous presentation of the disease, therapeutic standard is still controversial. This study analyzes treatment and outcome in these patients based on a large retrospective review and proposes a therapeutic algorithm. Methods The cases of 218 adult patients treated with deep neck abscesses over a 10-year period at a tertiary university hospital were analyzed retrospectively. Clinical, radiological, microbiological and laboratory findings were compared between patients with and without mediastinal involvement. Results Forty-five patients (20.64%) presented with abscess formation descending into the mediastinum. Those patients had significantly (all items p < 0.0001) higher rates of surgical interventions (4.27 vs. 1.11) and tracheotomies (82% vs. 3.4%), higher markers of inflammation (CRP 26.09 vs. 10.41 mg/dl), required more CT-scans (3.58 vs. 0.85), longer hospitalization (39.78 vs 9.79 days) and more frequently needed a change in antibiotic therapy (44.44% vs. 6.40%). Multi-resistant pathogens were found in 6.67% vs. 1.16%. Overall mortality rate was low with 1.83%. Conclusion Despite of the high percentage of mediastinal involvement in the present patient collective, the proposed therapeutic algorithm resulted in a low mortality rate. Frequent CT-scans, regular planned surgical revisions with local drainage and lavage, as well as an early tracheotomy seem to be most beneficial regarding the outcome. KW - tracheotomy KW - deep neck infection KW - mediastinitis KW - surgical drainage KW - microbiology Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266814 SN - 1434-4726 VL - 279 IS - 3 ER - TY - JOUR A1 - Kraus, Fabian A1 - Hackenberg, Stephan A1 - Shehata-Dieler, Wafaa A1 - Hagen, Rudolf T1 - High-sensitivity FEES\(^{®}\) with the professional image enhancement technology "PIET" JF - European Archives of Oto-Rhino-Laryngology N2 - Purpose Flexible endoscopic evaluation of swallowing (FEES\(^{®}\)) is a standard diagnostic tool in dysphagia. The combination of FEES® and narrow band light (narrow band imaging; NBI) provides a more precise and detailed investigation method. So far, this technique could only be performed with the NBI illumination. The new version of the "professional image enhancement technique" (PIET) provides another image enhancing system. This study investigates the eligibility of PIET in the FEES\(^{®}\) procedure. Methods Both techniques, NBI and PIET, were compared using a target system. Furthermore, the image enhancement during FEES\(^{®}\) was performed and recorded with the two systems during daily routine. Results Performing an image enhancement during FEES\(^{®}\) is possible with both systems PIET and NBI. On the target system, the contrast of the PIET showed a brighter and a more detailed picture. In dysphagia patients, no difference between PIET and NBI was detected. Conclusion PIET proved to be non-inferior to NBI during image enhancement FEES\(^{®}\). So far, image enhancement FEES\(^{®}\) was exclusively connected to NBI. With the PIET system, an alternative endoscopy technology is available for certain indications. KW - aspiration KW - high-sensitivity FEES KW - narrow band imaging (NBI) KW - professional image enhancement technique (PIET) KW - dysphagia Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266822 SN - 1434-4726 VL - 279 IS - 1 ER - TY - JOUR A1 - Müller-Graff, Franz-Tassilo A1 - Ilgen, Lukas A1 - Schendzielorz, Philipp A1 - Voelker, Johannes A1 - Taeger, Johannes A1 - Kurz, Anja A1 - Hagen, Rudolf A1 - Neun, Tilmann A1 - Rak, Kristen T1 - Implementation of secondary reconstructions of flat-panel volume computed tomography (fpVCT) and otological planning software for anatomically based cochlear implantation JF - European Archives of Oto-Rhino-Laryngology N2 - Purpose For further improvements in cochlear implantation, the measurement of the cochlear duct length (CDL) and the determination of the electrode contact position (ECP) are increasingly in the focus of clinical research. Usually, these items were investigated by multislice computed tomography (MSCT). The determination of ECP was only possible by research programs so far. Flat-panel volume computed tomography (fpVCT) and its secondary reconstructions (fpVCT\(_{SECO}\)) allow for high spatial resolution for the visualization of the temporal bone structures. Using a newly developed surgical planning software that enables the evaluation of CDL and the determination of postoperative ECP, this study aimed to investigate the combination of fpVCT and otological planning software to improve the implementation of an anatomically based cochlear implantation. Methods Cochlear measurements were performed utilizing surgical planning software in imaging data (MSCT, fpVCT and fpVCT\(_{SECO}\)) of patients with and without implanted electrodes. Results Measurement of the CDL by the use of an otological planning software was highly reliable using fpVCT\(_{SECO}\) with a lower variance between the respective measurements compared to MSCT. The determination of the inter-electrode-distance (IED) between the ECP was improved in fpVCT\(_{SECO}\) compared to MSCT. Conclusion The combination of fpVCT\(_{SECO}\) and otological planning software permits a simplified and more reliable analysis of the cochlea in the pre- and postoperative setting. The combination of both systems will enable further progress in the development of an anatomically based cochlear implantation. KW - interelectrode-distance KW - Cochlear duct length KW - Cochlear planning software KW - fpVCT KW - secondary reconstruction KW - MSCT Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-266798 SN - 1434-4726 VL - 279 IS - 5 ER -