Development of computer-aided surgery for otorhinolaryngology.

Computer-aided surgery (CAS) describes a method that allows intraoperative navigation in the surgical field based on digital image data such as computed tomography, magnetic resonance imaging, and others. A computer processes the image data in real time and is intraoperatively connected to a measuring system for coordinate determination. CAS has been used in ENT surgery since 1986, and we developed several generations of CAS systems. A passive robot arm was employed in the first approach. Then electromechanical and infrared optical coordinate-measuring devices followed. CAS was applied to several fields of otorhinolaryngologic surgery, including the paranasal sinuses, the orbit, the rhino- and otobasis, and others. CAS was found to be particularly useful for acoustic neuroma removal, paranasal sinus surgery in cases of massive disease or revision surgery, decompression of the orbit or optic nerve, extraction of deep-seated foreign bodies, stereotaxy-like biopsies, and educational purposes. CAS in its current state of development is a useful tool that can be applied routinely; however, further technical developments are necessary.