Abstract
The surgical goals for cholesteatomas are to remove diseased tissue, to make a dry “safe” ear, to preserve normal anatomy, and to improve hearing. However, the rates of recurrent and residual cholesteatoma have been reported to be very high. To prevent residual cholesteatoma, hidden area control is necessary. To prevent recurrent cholesteatoma, restoring ventilation and mastoid preservation are also important. Recently, transcanal endoscopic ear surgery, TEES (Transcanal Endoscopic Ear Surgery), has been introduced for cholesteatoma surgery. TEES enables hidden area control, restoration of ventilation, and mastoid preservation. In TEES, the pathologies extending to the retrotympanum are treated under direct endoscopic visualization. An anterior ventilation route is made by removing the tensor fold in addition to the posterior route via the isthmus. The indication for TEES has been limited to cholesteatomas within the attic, because transcanal atticotomy has been performed mainly with a curette. To extend the indication for TEES, we currently use powered instruments such as the Ultrasonic Surgical System and High-Speed Curved Bur, instead of the standard drills. Endoscopic retrograde mastoidectomy is achieved up to antrotomy by the use of powered instruments. With this procedure, removal of the bony canal wall is minimum. Endoscopic retrograde mastoidectomies require much less removal of the bony canal wall, which permits preservation of mucosa in the antrum. TEES with powered instruments has proved to be less invasive, secure and safe, and is a more functional procedure for cholesteatoma surgery.
