Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Hearing Preservation Outcomes in Patients With Sporadic Vestibular Schwannoma: Update

BACKGROUND: Given the increasing prevalence and shifting disease demographic of vestibular schwannoma toward smaller tumors in people with less advanced symptoms, increasing emphasis has been placed on functional hearing preservation. OBJECTIVE: To provide an update to the 2018 CNS Guideline on hearing preservation outcomes in patients with sporadic vestibular schwannoma. METHODS: Systematic review and clinical practice guideline summarizing data pertaining to hearing preservation outcomes within the first 10 years after contemporary stereotactic radiation, microsurgery, or observation with serial imaging. The analysis incorporates studies included in the 2018 guideline and additional literature published up to May 20, 2022, providing a comprehensive up-to-date review of published clinical outcome data over time. RESULTS: Pooled estimated rates of serviceable hearing preservation are presented for observation, radiosurgery, and microsurgery for adults with sporadic vestibular schwannoma who have documented serviceable hearing in the ipsilateral ear at the time of diagnosis. Overall estimated rates of maintaining serviceable hearing are 78% at 2 years, 59% at 5 years, and 47% at 10 years during observation; 71% at 2 years, 59% at 5 years, and 38% at 10 years after radiosurgery; and 48% at 2 years, 40% at 5 years, and 32% at 10 years after microsurgery. In addition, features portending hearing outcome among management modalities are reported to guide accurate patient counseling. CONCLUSION: Regardless of treatment modality, fewer than half of patients with sporadic vestibular schwannoma who present with serviceable hearing will maintain useful hearing by 10 years. Across all studies, microsurgery and radiosurgery seem to accelerate this decline over the natural history, although further research is needed given limitations of available evidence.