Zusammenfassung.
Ziel: Die Entwicklung und Evaluation einer auf CT-Daten basierenden präoperativen Implantationsprüfung im dreidimensionalen Raum am Beispiel einer intramastoidalen Hörgerätimplantation. Material und Methode: 10 mastoidektomierte Felsenbeinpräparate wurden computertomographisch untersucht. Die knöchernen Strukturen der hochauflösenden Spiral-CT-Daten wurden segmentiert und zusammen mit den Computer Aided Design (CAD)-Daten des Hörgerätes in eine Virtual Reality (VR)-Umgebung importiert. Drei Untersucher führten unabhängig voneinander eine dreidimensionale Einbauprüfung in der VR-Umgebung durch und bestimmten die Implantierbarkeit des Hörgerätes. Die virtuelle Implantationsprüfung wurde mit der realen, durch einen erfahrenen HNO-Chirurgen durchgeführten Implantation verglichen. Ergebnis: Das vorgestellte Verfahren ermöglichte eine gemeinsame dreidimensionale Darstellung und Manipulation von CT- und CAD-Daten in Echtzeit. Alle Objekte waren unabhängig von einander und frei in allen drei Dimensionen zu bewegen. Die virtuelle Implantationsprüfung stimmte in allen Fällen mit der realen Implantation überein. Die Implantabilität der 10 Felsenbeinpräparate wurde von allen drei Untersuchern richtig vorhergesagt. Schlussfolgerung: Der Einsatz eines VR-Systems in der Radiologie zeigte am Beispiel der Hörgerät-Implantationsprüfung ein hohes Potential für eine übersichtliche Implantationsplanung in komplexen anatomischen Regionen.
Feasibility of a pre-implantation fitting test for an implantable hearing aid using a VR (virtual reality) software.
Purpose: To prove the feasibility of a preoperative fitting test for an implantable hearing aid using a VR environment. Methods: A high-resolution spiral CT was performed after mastoidectomy in 10 temporal bone specimens. The bony structures were segmented and merged with the Computer-Aided Design (CAD) data of the hearing aid in a VR environment. For each specimen a three-dimensional fitting test was carried out by three examiners determining the implantability of the hearing aid. The implantation simulation was compared with the real implantation procedure performed by an experienced ENT surgeon. Results: The used VR system enabled real-time 3D-visualisation and manipulation of CT- and CAD-data. All objects could be independently moved in all three dimensions. The VR fitting test corresponded closely with the real implantation. The implantability of the hearing aid was properly predicted by all three examiners. Conclusion: Merging CT and CAD data in a virtual reality environment bears high potential for the presurgical determination of the fit and mountability of medical implants in complex anatomical regions.
Schlüsselwörter:
Virtuelle Realität - Computertomographie - Bildverarbeitung - Operationsplanung - Felsenbein
Key words:
Virtual reality - Simulation - Computed tomography - Image processing - Temporal bone
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Dr. med. Florian Dammann
Radiologische Universitätsklinik TübingenAbt. für Radiologische Diagnostik
Hoppe-Seyler-Straße 3
72076 Tübingen
Telefon: + 49-7071-29-82087
Fax: + 49-7071-29-5845
eMail: florian.dammann@med.uni-tuebingen.de
