Non-invasive registration in computer assisted craniomaxillofacial surgery

Computer-assisted technology was initially developed to provide neurosurgeons with precise guidance during surgical procedures. Currently available systems with and without robotic navigation are in use for specific medical indications. Various intraoperative navigation systems are used assisting surgery of the head and neck, such as endoscopic treatment of skull base [Kr96] and paranasal sinuses [An97], surgical corrections of posttraumatic deformities [MN98], orbital [KWM93], and orthognathic [Be96] surgery. The accuracy of electromagnetic, mechanical and optic systems has been investigated under laboratory conditions [Ro95] and seems to be sufficient especially in optical systems (0.1 mm). But under clinical conditions the accuracy of any navigation system mainly depends on the used referencing markers and the tracking system.