Transitory effect on endolymphatic hydrops of the intratympanic steroids for Ménière's disease.

OBJECTIVES/HYPOTHESIS This study aimed to evaluate the changes in electrocochleography (EcohG) measurements after intratympanic (IT) dexamethasone therapy and to correlate them with the long-term effects on the control of vertigo. STUDY DESIGN Prospective outcomes research. METHODS This study included 62 patients with unilateral Ménière's Disease (MD) refractory to medical therapy for at least 1 year. Each patient was treated with a fixed protocol of three consecutive weekly injections of a commercial 4 mg/mL dexamethasone preparation. The 1995 American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) criteria for reporting treatment outcomes for MD were used. Electrocochleography (EcohG) measurements were performed 1 month before and 1 and 12 months after IT steroid therapy. Caloric test and vestibular evoked myogenic potential (VEMPs) were performed before the IT treatment. The summating potential/action potential (SP/AP) ratio was measured before and after the IT treatment. A Kaplan-Meier analysis was used to evaluate the control of vertigo over a 2-year period. RESULTS Complete vertigo control (class A) was achieved in 26 patients (41.9%) at the 12-month follow-up and in 12 patients (19.3%) at the 24-month follow-up. A significant reduction (P < 0.01) in the SP/AP ratio after the IT steroid treatment was observed in the first-month determination, but no significant differences were found when the initial and 12-month determination were compared. CONCLUSIONS IT dexamethasone provides an alternative treatment for patients with Ménière's Disease. A transitory reduction of the endolymphatic hydrops is detected by the EcohG 1 month after treatment. The hydrops levels returned to their initial values in the 1-year EcohG follow-up. LEVEL OF EVIDENCE 2b.