Effects of a single intratympanic gentamicin injection on Meniere's disease

Conclusion. Both single and multiple injections of ITGM were effective in vertigo control and functional improvement. However, the risk of sensorineural hearing loss was much lower for a single injection than for multiple injections. Objectives. While intratympanic gentamicin injection (ITGM) has been established as treatment option for intractable Meniere's disease, several injection protocols have been introduced. The risk of sensorineural hearing loss (SNHL) has been reported to be variable for each protocol. Among the protocols, the single injection protocol is an easy to administer, well-tolerated and cost effective technique, as compared with others. We compared the clinical efficacy of ITGM with regard to the vertigo control rate and the incidence of SNHL between two different protocols: the use of single and multiple injections. Materials and Methods. A retrospective review was conducted for 30 subjects who were treated with ITGM with intractable unilateral Meniere's disease from May 1997 through February 2005. The patients were divided into two groups according to the protocol utilized: the multiple injection group (n = 10) and the single injection group (n = 20). Treatment efficacy was evaluated by using the AAO-HNS Committee on Hearing and Equilibrium guidelines (1995). Results. Effective vertigo control (Class A and B) were accomplished in 90% of patients in the multiple injection group and in 90% of patients in the single injection group. Functional status was also markedly improved in both groups. However, a significant hearing loss occurred more frequently in the multiple injection group (71%) than in the single injection group (5%). The rate of caloric loss was not different for the two groups (88% for the multiple injection group vs. 85% for the single injection group).