Long-term follow-up of transtympanic gentamicin for Meniere's syndrome

Objective: Recent studies have shown that transtympanic gentamicin for Meniere's syndrome is effective. Current treatment protocols vary. One concept has been to perform a chemical ablation; the other has been to perform a chemical alteration. Ablation requires multiple injections and is effective in controlling the vertigo, but it is associated with a significant incidence of hearing loss. Chemical alteration uses a minimal dose to reduce vestibular function without affecting cochlear function. Study Design: Prospective. Setting: Tertiary medical center. Patients: Patients had classic unilateral Meniere's syndrome that was unresponsive to medical therapy. Intervention: A single injection of gentamicin is given, and the patient is seen 1 month after injection. If indicated, the patient receives another injection and is reevaluated I month later. Main Outcome Measures: Control of vertigo and maintenance of hearing using the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HhTS) guidelines (1995). Results: Fifty-six patients have documented follow-up for 2 years or more, and 21 have 4 years or more of follow-up. This article presents the 4-year results as outlined by the AAO-HNS guidelines. Vertigo classes A and B were seen in 82% of patients. The patients followed 2 to 4 years had 86% vertigo class A and B results. Those followed 4 years or more show 76% with a vertigo class A or B result. In this study there has been minimal cochlear loss. There was vestibular change clinically, which was documented by electronystagmography. Conclusions: It appears that a single transtympanic gentamicin injection is effective in controlling the vertigo of Meniere's syndrome. Cochlear impact has been minimal. It is most useful for those patients who have failed medical management and are severely affected but not totally incapacitated by the disease.