Surgery for cholesteatoma in the petrous apex were reviewed. There are two main approaches reported up to now; middle cranial fossa approach and transmastoid approach. The latter involves translabyrinthine and extralabyrinthine approaches.Selection of them depends on whether or not cochlear function or facial nerve function is preserved. The extralabyrinthine approach is devided into five categories; supralabyrinthine, infralabyrinthine, precochlear, infracochlear, taranscanal-infrapetrosal approaches, which can be applied to other cystic lesions like cholesterol granuloma as well as cholesteatoma. Combind approaches with trans-and extra-labyrinthine approaches would be recommended in most of cases.How to deal with the lesion of cholesteatoma at surgery is another important surgical point in the treatment. Basic technique is to exteriorize the petrous lesion to the external auditory canal or mastoid.Alternative technique is to obliterate the lesion with fat or muscle, which should not be recommended because of high potential of recurrence inside the lesion.We have been trying to pneumatize inside the lesion after surgery by the method that the spaces after removal of cholesteatoma are obliterated with a small piece of muscle, and the other spaces only with fibrin glue. It was recognized that this maneuver facilitates aeration of the operative lesion including petrous apex, mastoids, middle ear space. Aerated lesion can have two important benefits; one is an early detection of recurrence of cholesteatoma on CT and MRI during follow up. Another is easy access to the petrous apex lesion because of an absence of barriers in the approach to the recurrent lesion if it could occur.
