Inner ear effects of topical gentamicin treatment in patients with Menière's disease

Several efforts have been made to treat patients with Menière's disease with ototoxic drugs. Lately the aminoglycoside antibiotic, gentamicin, has been favored. Several reports have proved its efficacy. In a series of 12 patients treated at the Karolinska Hospital in Stockholm, two patients failed to show improvement regarding their vertigo in spite of repeated courses of treatment. These patients both underwent labyrinthectomy where their vestibular sensory epithelia as well as portions of the cochlea were removed. The findings in these two cases were quite unanimous in that the vestibular sensory epithelia were retained showing advanced signs of degeneration. The organ of Corti in the cochlea was totally absent in all specimens examined. These findings indicate that gentamicin seems to affect the cochlea more than the vestibular sensory epithelia that also was clinically proven since both patients totally lost their hearing in the affected ear. Possible routes and actions of the drug in the inner ear are discussed.