Selective indications for the management of extensive anterior epitympanic cholesteatoma via combined transmastoid/middle fossa approach.

Abstract

Cholesteatoma that is present in the anterior epitympanic space may extend medially along the supralabyrinthine route to the geniculate ganglion, labyrinth, and cochlea and medially toward Kawase's triangle and the anterior petrous apex. Superiorly it may erode into the middle fossa. Contemporary microsurgical techniques allow for optimal management of these lesions with minimal morbidity, provided that the irregular and complex osteology of the petrous base is understood. The objective of the study was to review the relevant regional anatomy, pathobiology, and current algorithm used in treatment of this select patient population using a combined transmastoid/middle fossa (TM/MF) approach. A retrospective review was performed of all clinical and radiographic data from patients undergoing combined TM/MF management of extensive anterior epitympanic cholesteatoma between July 1984 and June 1998. Data from physical examinations, preoperative imaging studies, and operative findings and other relevant data were tabulated and analyzed for patients undergoing TM/MF management of cholesteatoma. Of 488 patients with cholesteatoma treated by the otological service between 1984 and 1998, 11 patients underwent TM/MF exposure and removal of anterior epitympanic cholesteatoma. Total cholesteatoma removal was accomplished in six patients. In three patients, because of facial nerve involvement, labyrinthine fistulae, or internal carotid artery involvement, open-cavity surgery was performed. In two patients, residual or recurrent cholesteatoma was exteriorized at "second-look" procedures. In this small cohort of patients the majority had extension to the arcuate eminence, geniculate ganglion, or Kawase's triangle or had "blue-lining" of the cochlea or labyrinth. To a lesser degree, the middle ear and mastoid contents were involved. Further facial nerve dysfunction or sensorineural hearing loss was not noted after surgery. Selective TM/MF removal of cholesteatoma provides an optimal route for removing complex cholesteatoma in patients with intact sensorineural function and medial cholesteatoma extension.