Hearing Outcomes after Surgical Drainage of Petrous Apex Cholesterol Granuloma

Objective: To assess the hearing outcomes of patients undergoing surgical management of petrous apex cholesterol granuloma.

Background: Petrous apex cholesterol granulomas may present with progressive sensorineural hearing loss, which is often secondary to otic capsule erosion or 8th nerve compression. Surgical drainage using an otic capsule-sparing perilabyrinthine approach (infracochlear or infralabyrinthine), in some cases, may prevent further progression of hearing loss. These two approaches preserve the integrity of the otic capsule and potentially allow hearing preservation.

Design: Retrospective chart review with IRB approval.

Setting: Tertiary care medical center.

Patients: Nine patients underwent surgery from 2002-2011 with adequate records for review.

Main Outcome Measures: Preoperative and postoperative audiogram results as measured by pure tone average, speech discrimination, and speech recognition threshold.

Results: Five patients (55%) demonstrated improvement in either speech discrimination or pure tone averages. Two patients (22%) had complete loss of hearing. Two patients (22%) showed no change in hearing.

Conclusion: Perilabyrinthine drainage of petrous apex cholesterol granulomas allows for hearing preservation and improvement in most cases, even in the setting of otic capsule erosion. Patients should be counseled about the potential risk of significant hearing loss.