Acoustic neuroma removal by the retrosigmoid approach: Hearing preservation

Predictors of preservation of Gardner and Robertson Class 1 or 2 hearing were determined for a series of 155 consecutive acoustic neuromas operated on by the retrosigmoid approach. Size (mean extracanalicular tumor diameter) (p < 0.001), intraoperative cochlear action potential threshold shift (< 20 dB) (p < 0.0001) and sex (female) (p=0.01) were predictors of serviceable hearing preservation. Patient age, tumor side and preoperative hearing were not predictive of outcome. Facial nerve function at follow-up was House and Brackmann(3) Grade I or II in 94%.