Artma Medizintechnik GmbH, Am Kanal 27, A-1110 Wien, Austria
*Clinic for Maxillofacial Surgery, University of Vienna, Austria
In computer aided surgery, the feasibility of computer navigation assistance by augmented reality has been proven for a wide variety of indications (1). Although data of imaging sources during operation provide help and useful information for the surgeon our research has shown that the future challenge is knowledge based surgery, using the Internet as communication backbone. In this paper we present a first clinical test.
The fundamental concept of the Virtual Patient System (Artma, Austria) is the real time fusion of medical imaging data like CT, MRI, c arm, ultrasound with video from the intraoperative situation (2). 3-D electronic sensors are rigidly attached to the patient, to any structures of intraoperative manipulation, and to surgical instruments, respectively. The patient's diagnostic data are used to assess the individual anatomy and pathology, and are set in relation for interactive on screen planning. The visualization of target structures and surgical approaches is realized by overlay graphics. The information is visualized in a heads up display (Vista Medical Technologies, Carlsbad, CA).
Recent developments in communication technology enable the broadcast of not only video data, but also of stereotactic navigation data via network. We transmit video and 3D sensor data via LAN, ISDN or Internet (3). Based on the transmitted stereotactic information, the actual graphic overlay structures used for intraoperative guidance are computed on the remote computer, thus dramatically reducing the bandwidth necessary for transmission.
To our knowledge, we performed the first stereotactic surgery teleconsultation in the field of maxillofacial surgery August 1996 in Austria. The surgical procedure was performed at the Clinic for Maxillofacial Surgery, University of Vienna, Austria. For teleconsultation the stereotactic position of a fractured bone segment was visualized in real time over a distance of 500 km at the Forum Alpbach, Tyrol. The expert at Alpbach analyzed the intraoperative situs according to symmetry, hard/soft tissue relation and occlusal details, according to his professional expertise gained in corresponding cases.
We have further expanded this concept with an interactive link from the expert back to the operating theater. The manipulation of graphical structures in stereotactic space relative to the patients anatomy at the remote computer workstation is transmitted in real time to the surgeon and visualized in his heads up display. First clinical experiences will be reported.
We plan to transmit live stereotactic surgical procedures from the Clinic for Maxillofacial Surgery, University of Vienna, Austria to the conference site.
(1) Virtual image guided navigation in tumor surgery. Wagner A, Ploder O, Enislidis G, Truppe M, Ewers R: J Cran Max Fac Surg 23, 271-273, 1995
(2) Interventional Video tomography. Truppe M, Pongracz F, Ploder O, Wagner A, Ewers R: Proceedings of Lasers in Surgery, 4-6 Feb. 1995, San Diego
(3) Teleassisted stereotactic endoscopic surgery. Truppe M, Freysinger W, Gunkel A, Thumfart W: Proceedings Computer Assisted Radiology CAR, Paris, June 1996, pp 686-692.