Low Concentration Intra-Tympanic Gentamicin Treatment for Menière's Disease: A Long-Term Follow Up.

BACKGROUND: Intra-tympanic injections of gentamicin (ITG), a known ototoxic agent, have been proven to be effective in controlling Menière's disease (MD) symptoms, in patients who did not respond to conservative therapy, although its safety was questionable. OBJECTIVES: To study whether low-concentration ITG, in refractory MD, had an effect on the ipsilateral hearing, in comparison to the contralateral ear, and to study the effectiveness of such treatment. METHODS: A comparative, retrospective cohort study was conducted between 2003 and 2015, and compared the change in the hearing level between the injected ear and the contralateral, untreated ear. OUTCOMES: In 20 of 27 patients (74.1%), one course of ITG treatment was considered as successful. In the short-term, there was improvement of hearing level at 1000 Hz (p = 0.014), and deterioration of hearing level at 8000 Hz (p = 0.039), both in comparison to the control ear. In the long-term and after confounders adjustment, we found there were no differences in the hearing levels between the treated ear and the untreated contralateral ear. CONCLUSIONS: A high success rates of treating vertigo attacks with low concentration ITG in refractory unilateral MD patients is herein reported, while a significant difference was not observed in the hearing threshold compared with the healthy contralateral ear.