Computer-assisted surgery (CAS) in sinus diseases.

Since the mid-80s, endonasal sinus surgery has gained significant importanc e in the treatment of chronic inflammatory sinus disease. Many surgeons hav e 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 n avigation (CAS) systems. Methods: Since 1996, we have tried several differe nt CAS systems for difficult surgical procedures in sinus and anterior skul l base surgery, mainly revision surgery for chronic inflammatory sinusitis and endonasal tumors. During this time, we tried one electromagnetic (,,Ins ta Trak") and two optoelectric systems (,,Surgigate" and,,Vector Vision"). Results: In our experience, all systems can be used in endonasal sinus surg ery: accuracy was satisfactory and varied between 0.1 and 0.5 mm. There wer e differences with respect to the time of preparation of the system for sur gery as well as to the possibility to use different instruments. Conclusion s: Computer-assisted surgical navigation systems today have gained a degree of accuracy which makes them not only suitable but almost necessary, at le ast for difficult surgical procedures at the anterior skull base, i.e. revi sion surgery in chronic inflammatory sinus disease. On the long run, these systems will become mandatory for these kinds of procedures. On the other h and, CAS systems cannot substitute thorough anatomical and surgical trainin g.