gms | German Medical Science

Introduction: Sinus surgery training is restricted to cadaver dissections up to now. A virtual training system would be of high value for the understanding of three dimensional anatomy and for surgical education. Most existing are not satisfying and are accessable only to a limited number of users.

Methods: A three dimensional voxel model was established on basis of CT data by segmentation of the anatomic structures. Navigation is done microscopically or endoscopically with additional real time CT navigation. Visualization, haptic rendering, and tissue removal are performed with subvoxel resolution. Surgical instruments are controlled with a standard haptic device. Resected parts of the bone are simultaneously indicated by colour in the navigation CT.

Figure 1 [Fig. 1], Figure 2 [Fig. 2], Figure 3 [Fig. 3]

Results: Stepless surgical procedures can be simulated in a reproducable way. Critical surgical situations are documented and indicated audio-visually by an implemented alert and documentation module. Navigation inside of the model works well. The haptic device provides a realistic feel of the procedure. Surgical procedures are limited to tissue removal since the simulation of soft tissue deformation is not satisfyingly possible up to now. The running stability was excellent.

Conclusion: The presented system interactively teaches surgical anatomy of the inner nose and paranasal sinuses. For this purpose it may be used with predefined training cases. It allows simulation of endonasal and even extranasal sinus surgery with a high degree of reality and includes validation tools. Up to now it is mainly a training system for sinus surgery novices. Future developments include preoperative processing of patient specific data for rehearsal of individual procedures as well as interactive training tutorials.