Retrosigmoid Approach for Small and Medium-sized Acoustic Neuromas

OBJECTIVE: Clinical study of the keyhole acoustic neuroma retrosigmoid approach for facial nerve and hearing preservation. STUDY DESIGN: This was a prospective case review from October 1993 to December 1998 in a referral hospital care unit. PATIENTS: A total of 119 consecutive patients with a tumor size of <25 mm in the cerebellopontine angle corrected by a retrosigmoid approach were included in the study. INTERVENTIONS: Standard audiometric and imaging assessments, complete tumor removal by using endoscopy-assisted control, and nerve monitoring. MAIN OUTCOME MEASURES: House-Brackmann facial nerve grade and hearing level by the American Academy of Otolaryngology-Head and Neck Surgery classification. RESULTS: Grades I and II facial nerve function was obtained in 96% of cases, measurable hearing was preserved in 49% of cases, and 30% of cases achieved serviceable hearing. CONCLUSION: The retrosigmoid approach is a safe and reliable approach in random patients with small and medium-sized acoustic neuromas.