Auditory results after vestibular nerve section and intratympanic gentamicin for Meniere's disease

Objective: Hearing loss is a possible complication of vestibular neurectomy and intratympanic gentamicin administration in Meniere's disease. The aim of this study was to compare the incidence of this complication with the two treatments. Study Design: Retrospective review. Setting: Tertiary referral center. Patients: The initial study population reviewed consisted of 24 patients receiving gentarnicin injections and 209 patients undergoing vestibular nerve section. Comparison of data was performed among all 24 intratympanic gentamicin patients and the last 24 vestibular neurectomy patients operated on via the retrosigmoid approach. Interventions: Intratympanic gentarmicin administration (26156 mg) and retrosigmoid vestibular neurectomy. Main Outcome Measure: Auditory and vertigo results were evaluated according to the American Academy of Otolaryngology 1995 criteria. Results: The mean preoperative pure-tone average for patients undergoing vestibular nerve section was 48.5 dB, with a speech discrimination score of 85%. In these patients, the postoperative pure-tone average was 50.3 dB, and the speech discrimination score was 82%. Patients undergoing gentamicin injection had a mean pretreatment pure-tone average of 50.1 dB and a speech discrimination score of 87%. The posttreatment pure-tone average and discrimination score for the gentamicin group were 74.7 dB and 65%, respectively. The amount of postprocedure hearing loss was significantly greater in the gentarnicin group (p = 0.03). Excellent control of vertigo (classes A and 13) was obtained in 95.8% of the patients treated with vestibular nerve section and in 75% of the patients in the gentamicin group. Conclusion: Gentamicin administration and vestibular neurectomy are both effective for relieving vertigo in Meniere's disease. The incidence of hearing loss is significantly higher after gentarnicin injection.