@article{TaegerMuellerGraffNeunetal.2021, author = {Taeger, Johannes and M{\"u}ller-Graff, Franz-Tassilo and Neun, Tilmann and K{\"o}ping, Maria and Schendzielorz, Philipp and Hagen, Rudolf and Rak, Kristen}, title = {Highly precise navigation at the lateral skull base by the combination of flat-panel volume CT and electromagnetic navigation}, series = {Science Progress}, volume = {104}, journal = {Science Progress}, number = {3}, issn = {2047-7163}, doi = {10.1177/00368504211032090}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-250268}, year = {2021}, abstract = {This study aimed to evaluate the feasibility and accuracy of electromagnetic navigation at the lateral skull base in combination with flat panel volume computed tomography (fpVCT) datasets. A mastoidectomy and a posterior tympanotomy were performed on 10 samples of fresh frozen temporal bones. For registration, four self-drilling titanium screws were applied as fiducial markers. Multi-slice computed tomography (MSCT; 600 µm), conventional flat panel volume computed tomography (fpVCT; 466 µm), micro-fpVCT (197 µm) and secondary reconstructed fpVCT (100 µM) scans were performed and data were loaded into the navigation system. The resulting fiducial registration error (FRE) was analysed, and control of the navigation accuracy was performed. The registration process was very quick and reliable with the screws as fiducials. Compared to using the MSCT data, the micro-fpVCT data led to significantly lower FRE values, whereas conventional fpVCT and secondary reconstructed fpVCT data had no advantage in terms of accuracy. For all imaging modalities, there was no relevant visual deviation when targeting defined anatomical points with a navigation probe. fpVCT data are very well suited for electromagnetic navigation at the lateral skull base. The use of titanium screws as fiducial markers turned out to be ideal for comparing different imaging methods. A further evaluation of this approach by a clinical trial is required.}, language = {en} } @article{MuellerGraffIlgenSchendzielorzetal.2022, author = {M{\"u}ller-Graff, Franz-Tassilo and Ilgen, Lukas and Schendzielorz, Philipp and Voelker, Johannes and Taeger, Johannes and Kurz, Anja and Hagen, Rudolf and Neun, Tilmann and Rak, Kristen}, title = {Implementation of secondary reconstructions of flat-panel volume computed tomography (fpVCT) and otological planning software for anatomically based cochlear implantation}, series = {European Archives of Oto-Rhino-Laryngology}, volume = {279}, journal = {European Archives of Oto-Rhino-Laryngology}, number = {5}, issn = {1434-4726}, doi = {10.1007/s00405-021-06924-0}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-266798}, pages = {2309-2319}, year = {2022}, abstract = {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.}, language = {en} } @phdthesis{Ilgen2023, author = {Ilgen, Lukas}, title = {Ermittlung cochle{\"a}rer L{\"a}ngen- und Winkelmaße mittels Flachdetektor-Volumen-Computertomographie - Evaluation der Anwendung sekund{\"a}rer Rekonstruktionen}, doi = {10.25972/OPUS-32794}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-327945}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2023}, abstract = {F{\"u}r die Cochlea-Implantat-Versorgung ist die Kenntnis der individuellen Anatomie der H{\"o}rschnecke im perioperativen Kontext essenziell, um ein suffizientes audiologisches Resultat sicherzustellen. Ein akkurates Verfahren hierf{\"u}r stellt die 3D multiplanare Rekonstruktion (3D-curved MPR) in Schnittbildgebung dar. Notwendige Voraussetzung ist jedoch eine hinreichende Bildqualit{\"a}t. In dieser Arbeit wurde das Augenmerk auf die sekund{\"a}re Rekonstruktion von Prim{\"a}rdatens{\"a}tzen der Flachdetektor-Volumen-Computertomographie (fpVCTSECO) gerichtet. Diese bietet n{\"a}mlich die M{\"o}glichkeit, die Bildqualit{\"a}t zu steigern, ohne jedoch eine als kritisch einzusch{\"a}tzende Dosissteigerung in Kauf nehmen zu m{\"u}ssen. Es konnte gezeigt werden, dass es f{\"u}r die Messung der L{\"a}nge von 2 Schneckenwindungen (2TL), der gesamten cochle{\"a}ren L{\"a}nge (CDL) und dem Winkelmaß (AL) mittels 3D-curved MPR in der fpVCT keinen signifikanten Unterschied gegen{\"u}ber der Mehrschicht-CT gibt. In beiden Modalit{\"a}ten wurden alle drei Parameter gegen{\"u}ber der Referenzbildgebung micro-CT deutlich untersch{\"a}tzt. Durch die fpVCTSECO war es m{\"o}glich, die Genauigkeit der Messungen zu steigern und den Werten der Referenz anzun{\"a}hern. Lediglich f{\"u}r AL muss eine geringf{\"u}gige systematische Untersch{\"a}tzung beachtet werden. Postoperativ zeigte sich mit einliegendem Elektrodentr{\"a}ger f{\"u}r 2TL eine ebenso pr{\"a}zise Messung wie pr{\"a}operativ ohne. Jedoch wurde die CDL um circa 0,5 - 0,7 mm untersch{\"a}tzt. Urs{\"a}chlich hierf{\"u}r d{\"u}rften vor allem Metallartefakte gewesen sein. Auch wenn die 3D-curved MPR in Kombination mit der fpVCTSECO postoperativ zur Visualisierung der r{\"a}umlichen Beziehung von Elektrodentr{\"a}ger, Modiolus und oss{\"a}rer lateraler Wand sehr gut geeignet war, so muss sich der Einfluss dieser Diskrepanz f{\"u}r die audiologische Anpassung in Zukunft erst noch zeigen.}, subject = {Cochlea}, language = {de} }