Late failure rate of hearing preservation after middle fossa approach for resection of vestibular schwannoma

Objective: To explore the long-term hearing results after a middle fossa approach for resection of vestibular schwannoma. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: All patients undergoing a middle fossa approach for resection of vestibular schwannoma at a single institution with intent to preserve hearing between December 1989 and December 2009 were included in the study population. Interventions: Standard middle fossa approach for resection of vestibular schwannoma, magnetic resonance imaging (MRI), and audiogram. Main Outcome Measures: Recurrence of tumor as evaluated by MRI and hearing results as measured by serial audiograms. Results: Seventy-eight patients were identified who met study criteria. Fifty-one (65%) of the 78 patients had usable hearing (American Academy of Otolaryngology-Head and Neck Surgery [AAO-HNS] class A or B) postoperatively. Forty-four patients with successful hearing preservation had follow-up beyond their initial postoperative visit. Five (11%) of the 44 patients showed late degradation to nonserviceable hearing (AAO-HNS class C or D) over a mean follow-up of 4.0 years. Kaplan-Meier estimate of preservation of class A or B hearing at 10 years was 72%. Of the five patients with late degradation in hearing, 2 were found to have recurrences of their original tumor on MRI. There were 5 confirmed recurrences in the total study population. Conclusion: Late degradation of hearing was an infrequent occurrence after initially successful hearing preservation. When hearing degradation did occur, there seemed to be a correlation with tumor recurrence.