Retrolabyrinthine vestibular neurectomy with simultaneous monitoring of eighth nerve action potentials and electrocochleography.

Since November 1978, we have used retrolabyrinthine vestibular neurectomy in 29 of 42 cases as the primary procedure to relieve vertigo in Meniere's disease. The results indicate that 67% of patients had no vertigo postoperatively, while 21% were much improved. Hearing was maintained within 20 dB of the preoperative level in 78%. Simultaneous intraoperative electrocochleography and eighth nerve action potentials were used to monitor auditory function in the last fourteen cases using an Amplaid Mark V evoked potential signal processor. It appears that the intraoperative electrocochleography after vestibular neurectomy can be used as an indicator of postoperative auditory function. The retrolabyrinthine vestibular neurectomy has replaced the middle fossa vestibular neurectomy and the endolymphatic subarachnoid shunt in our practice.