Preliminary results of a new delivery system for gentamicin to the inner ear in patients with Meniere's disease

Intratympanic gentamicin therapy has gained some clinical popularity in the treatment of vertigo associated with Meniere's disease. This therapeutic m odality offers some advantages over traditional surgical treatment. The ves tibulotoxic effect of gentamicin is well documented, but there is no genera l agreement about the dose needed to control vertigo attacks without affect ing hearing. In the current preliminary study 27 patients with Meniere's di sease refractory to medical management were treated by small doses of genta micin delivered via microcatheter in the round window niche and administere d by an electronic micropump. The patients received a total dose of 0.24-90 mg. The effect on vestibular symptoms resulted in the cessation of vertigo in the 22 patients, control of drop attacks in 4 of 6, and release of aura l pressure and fullness in 2 of 4. Significant hearing loss (anacusis) occu rred in six patients, slightly related to the flow rate in the pump setting . Different explanations for the loss of hearing are presented. The new del ivery system for gentamicin appears to be effective in controlling vertigo, but with an unacceptable negative effect on hearing. The effectiveness and the safety of this new delivery system must be investigated further in con trolled studies. However, it opens up the possibility of future novel ways of treating inner ear diseases, such as sudden deafness and tinnitus, as we ll as for the protection, repair, and regeneration of inner ear sensory cel l function in damage due to aging, noise, toxic substances, immune reaction s, etc.