Transcochlear repair of persistent cerebrospinal fluid leaks

Objective: The purpose of this study is to demonstrate the utility of a mod ified transcochlear obliteration of the petrous apex in repair of persisten t cerebrospinal fluid (CSF) leaks. A review of temporal bone computed tomog raphy (CT) scans and histological preparations for potential air cells lead ing to such leaks is also presented. Study Design: Retrospective case revie w in an academic tertiary referral center, Methods: Patients for inclusion in this study had previously undergone either a suboccipital or translabyri nthine removal of an intracranial tumor with subsequent transmastoid and mi ddle ear obliteration of air cell tracts to stop a CSF leak. Ninety CT scan s and 178 temporal bones were reviewed and assessed for peritubal and petro us apex pneumatization, Results: Four patients had initial obliteration of the orifice of the eustachian tube and middle ear that failed to prevent le akage of CSF, The leak was ultimately controlled by a transcochlear petrous apicectomy. From The Ohio State University temporal bone collection, 178 s pecimens were available for examination. Peritubal pneumatization was found in 42% of the bones examined. The CT scans showed unilateral petrous apex pneumatization in 30% of the specimens and bilateral pneumatization in 11%, Conclusions: Continuity of air cell tracts from the petrous apex surroundi ng the internal auditory canal to the medial eustachian tube can provide a path for CSF rhinorrhea that is difficult to stop by conventional means. A modified transcochlear approach successfully terminated persistent leaks in four such patients.