Brain herniation into the middle ear and mastoid: concepts in diagnosis and surgical management.

Objective: To review the occurrence characteristics of and clinical repair experience with brain herniation in to the middle ear and mastoid from 1970-1995.

Study Design: Retrospective chart/case review.

Setting: Private Otology/Neurotology referral practice.

Patients: Thirty-five patients with temporal bone brain herniation diagnosed and treated from 1970-1995.

Intervention: Diagnosis confirmed by CT and/or MRI. Treatment was surgical.

Main Outcome Measures: Success of surgical repair of the problem in a large experience with follow-up of up to 180 months (mean, 48.7 months).

Results: Diagnosis is most effectively made by both (computed tomography (CT) and magnetic resonance imaging (MRI). In this series diagnosis was accurate in 89% with MRI. Primary repair was successful in all but three patients, two of whom required a second repair. One was unreconstructable.

Conclusions: Temporal bone encephaloceles occur after ear surgery and in chronic otitis media. Prompt and effective surgical repair is successful and integral to complication avoidance.