Facial Nerve Outcomes After Vestibular Schwannoma Microsurgical Resection in Neurofibromatosis Type 2
Catherine E. Sobieski, Daniel E. Killeen, Samuel Barnett, Bruce Mickey, Jacob B. Hunter, Brandon Isaacson, Joe Walter Kutz
Abstract
Objective The aim of this study is to investigate facial nerve outcomes after microsurgical resection in neurofibromatosis type 2 (NF2) compared to sporadic tumors. Study Design Single institutional retrospective chart review. Setting Tertiary referral center. Methods All adult patients with NF2 vestibular schwannoma (VS) or sporadic VS who underwent microsurgical resection from 2008 to 2019 with preoperative magnetic resonance imaging (MRI) and 1 year of postsurgical follow‐up were included. The primary outcome measure was postoperative House‐Brackmann (HB) facial nerve score measured at first postoperative visit and after at least 10 months. Results In total, 161 sporadic VSs and 14 NF2 VSs met inclusion criteria. Both median tumor diameter (NF2, 33.5 mm vs sporadic, 24 mm, P =. 0011) and median tumor volume (NF2, 12.4 cm 3 vs sporadic, 2.9 cm 3 , P =. 0005) were significantly greater in patients with NF2. The median follow‐up was 24.9 months (range, 12‐130.1). Median facial nerve function after 1 year for patients with NF2 was HB 3 (range, 1‐6) compared to HB 1 (range, 1‐6) for sporadic VS ( P =. 001). With multivariate logistic regression, NF2 tumors (odds ratio [OR] = 13.9, P =. 001) and tumor volume ≥3 cm 3 (OR = 3.6, P =. 025) were significantly associated with HB ≥3 when controlling for age, sex, extent of tumor resection, translabyrinthine approach, and prior radiation. Conclusion Tumor volume >3 cm 3 and NF2 tumors are associated with poorer facial nerve outcomes 1 year following microsurgical resection.