Effect of edaravone on streptomycin-induced vestibulotoxicity in the Guinea pig

OBJECTIVES/HYPOTHESIS: The effect of topical administration of edaravone to the inner ear was investigated in guinea pigs with streptomycin-induced vestibulotoxicity. METHODS: Vestibulotoxicity was induced in 20 animals by delivery of streptomycin into the inner ear through osmotic pump for 24 hours. Edaravone (n = 8, systemic administration group) or saline (n = 6, control group) was injected intraperitoneally once a day for 7 days or edaravone-soaked Gelfoam was placed on the round window before wound closure (n = 6, topical administration group). RESULTS: Yaw head tilt and spontaneous nystagmus were observed in all animals after the operation. The number of spontaneous nystagmus beats in the topical administration group was statistically less than that in other two groups at 12, 18, and 24 hours after the operation. CONCLUSION: The study results suggest that topical administration of edaravone better suppresses streptomycin-induced vestibulotoxicity than systemic administration.