Rate of Hearing Preservation After Stereotactic Radiosurgery for Treatment of Vestibular Schwannoma: Analysis of Patients With 100% Word Recognition Scores

Objective: To evaluate hearing outcomes after treatment with stereotactic radiosurgery (SRS) for sporadic vestibular schwannoma (VS) among patients with baseline 100% word recognition scores (WRS). Study design: Historical cohort. Setting: Tertiary academic medical center. Patients: Patients with 100% WRS on audiometric testing at initial treatment with SRS. Interventions: Gamma Knife SRS. Main outcome measures: Rate of maintaining serviceable hearing (SH), defined as American Academy of Otolaryngology-Head and Neck Surgery hearing class A or B. Results: In total, 125 patients had 100% WRS at SRS for sporadic VS. Median age at SRS was 56 years (IQR: 51 to 62) and median pure tone average (PTA) at SRS was 20 dB HL (IQR: 13 to 31). Sixty-eight patients progressed to non-SH at a median of 3.4 years after SRS (IQR: 1.0 to 8.6); the median duration of follow-up for the 57 patients who maintained SH was 5.1 years (IQR: 2.8 to 9.6). Rates of maintaining SH (95% CI, number still at risk) at 1, 3, 5, 7, and 10 years after SRS were 88% (82 to 94, 101), 75% (68 to 84, 81), 61% (53 to 71, 55), 58% (49 to 68, 43), and 44% (35 to 56, 26), respectively. Each 10-dB HL increase in PTA at SRS was associated with a 52% increased risk of progression to non-SH (hazard ratio: 1.52, 95% CI: 1.24-1.87, P <0.001). Conclusions: Despite having 100% pretreatment WRS, most patients with sporadic VS treated with SRS experienced clinically significant hearing decline over time. Even among this cohort of patients with excellent baseline hearing, at 10 years after treatment, only 44% of patients maintained SH.