Long-term hearing preservation after surgery for vestibular schwannoma

Abstract
Object. Vestibular schwannomas (VSs) are now amenable to resection with excellent hearing preservation rates. It remains unclear whether immediately postoperative hearing is a durable result and will not diminish over time. The aim of this study was to determine the rate of long-term preservation of functional hearing following surgery for a VS and to examine factors influencing hearing preservation. Methods. All patients eligible for hearing preservation (Gardner—Robertson Class I or II) who had undergone resection of a VS by a single surgeon were reviewed retrospectively. Follow-up audiograms and magnetic resonance images were obtained. Of 142 patients deemed eligible for hearing preservation surgery, 38 had immediate postoperative hearing confirmed by an audiogram. In these patients with preserved hearing, the audiographic results demonstrated functional hearing in 30 (85.7%) of 35 patients who underwent repeated testing at a mean follow-up time of 7 years. Delayed hearing loss occurred in five (14.3%) of the 35 patients and did not correlate significantly with the size of the tumor. Hearing improved one Gardner—Robertson class postoperatively in three (7.9%) of the 38 patients. Conclusions. Long-term functional hearing was maintained in 85.7% of patients when it was preserved immediately postoperatively and the result was independent of tumor size. The results of this study emphasize that long-term preservation of functional hearing is a realistic goal following VS surgery and should be attempted in all patients in whom preoperative hearing is determined to be Gardner—Robertson Class I or II.