The Effect of Tumor Size on Likelihood of Hearing Preservation After Retrosigmoid Vestibular Schwannoma Resection.

ABSTRACT

OBJECTIVES: 1) Describe the effect of tumor size on the likelihood of hearing preservation after retrosigmoid approach for resection of vestibular schwannoma (VS).2) Describe the effect of preoperative hearing status on the likelihood of hearing preservation. STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS Adult (18 years or older) patients underwent retrosigmoid VS resection and postoperative audiometry between 2008 and 2018 and had a preoperative word recognition score (WRS) of at least 50%. Patients with a history of neurofibromatosis 2, radiation, or previous resection were excluded. INTERVENTIONS: All patients underwent retrosigmoid VS resection with attempted hearing preservation. MAIN OUTCOME MEASURES: WRS of at least 50%. RESULTS: Data from 153 patients were analyzed. Mean age was 50.8 (±11.3) years and mean tumor size 14 (±6) mm. Hearing was preserved and lost in 64 (41.8%) and 89 (58.2%) patients, respectively. Hearing preservation rates were higher for intrameatal tumors than for tumors with extrameatal extension (57.6% versus 29.4%, p = 0.0005). On univariate and multivariate regression analysis, tumor size (per mm increase) was a negative predictor of hearing preservation (odds ratio [OR] 0.893, p = 0.0002 and 0.841, p = 0.0005, respectively). Preoperative American Academy of Otolaryngology-Head & Neck Surgery Hearing Class was also predictive of hearing preservation (p = 0.0044). Class A hearing (compared with class B hearing) was the strongest positive risk factor for hearing preservation (OR 3.149, p = 0.0048 and 1.236, p = 0.0005, respectively). CONCLUSION: Small tumor size and preoperative class A hearing are positive predictors of hearing preservation in patients undergoing the retrosigmoid approach for VS resection.