Computer-assisted surgery (CAS) in sinus diseases.

Since the mid-80s, endonasal sinus surgery has gained significant importance in the treatment of chronic inflammatory sinus disease. Many surgeons have recognized the necessity of developing new methods to increase the safety of this type of surgery. One of the advancements in increasing the safety of endonasal sinus surgery was the development of computer-aided surgical navigation (CAS) systems. Methods: Since 1996, we have tried several different CAS systems for difficult surgical procedures in sinus and anterior skull base surgery, mainly revision surgery for chronic inflammatory sinusitis and endonasal tumors. During this time, we tried one electromagnetic (,,Insta Trak") and two optoelectric systems (,,Surgigate" and,,Vector Vision"). Results: In our experience, all systems can be used in endonasal sinus surgery: accuracy was satisfactory and varied between 0.1 and 0.5 mm. There were differences with respect to the time of preparation of the system for surgery as well as to the possibility to use different instruments. Conclusions: Computer-assisted surgical navigation systems today have gained a degree of accuracy which makes them not only suitable but almost necessary, at least for difficult surgical procedures at the anterior skull base, i.e. revision surgery in chronic inflammatory sinus disease. On the long run, these systems will become mandatory for these kinds of procedures. On the other hand, CAS systems cannot substitute thorough anatomical and surgical training.