A 25 Year Update on the Facial Nerve Sparing Approach for Vestibular Schwannoma.

Background And Objectives: This article aims to report results of our facial nerve preservation approach to treating vestibular schwannomas (VS) at a single institution by a single surgeon performing both microsurgery (MS) and stereotactic radiosurgery (SRS).

Methods: We retrospectively reviewed 751 patients at our institution between 1998 and 2023 by intervention received: retrosigmoid microsurgery (MS, Group 1, 217 patients), gamma knife stereotactic radiosurgery (SRS, Group 2, 462 patients), MS then SRS (Group 3, 72 patients), SRS then MS (Group 4, 10 patients), and SRS then SRS (Group 5, 5 patients). No patients had MS followed by MS. The primary outcome variable was postoperative facial nerve function.

Results: Good outcomes (defined as House-Brackmann grade ≤2 at last follow-up) across treatment groups were 98.2%, 99.6%, 93.1%, 90%, and 100%, respectively, with 96.9% and 99.4% of patients treated with upfront MS and upfront SRS, respectively, having a good outcome. For groups who received more than one treatment (3, 4, 5), the mean time between treatment and progression was 48.8, 35.7, and 95.8 months, respectively. No patients underwent additional treatment following salvage treatment. The median (IQR) follow-up time among patients with a minimum follow-up of 12 months was 52 (26.75-88) months, with a maximum of 297 months (24.75 years).

Conclusions: For patients with VS not undergoing primary SRS, MS with an emphasis on facial-nerve preservation over gross total resection followed by surveillance imaging and adjuvant SRS is an effective treatment paradigm that yields excellent facial nerve outcomes, low morbidity, and acceptable tumor control.