Vestibular Nerve Section for Meniere's Disease

Abstract

Retrosigmoid vestibular nerve section was performed in two patients with Meniere's disease to relieve intractable vertigo. During surgery, the auditory brain stem evoked response (ABR) and direct compound action potentials (CAP) from the cochlear nerve were recorded simultaneously. The first patient, a 49-year-old woman, had a 2-year history of episodic vertigo and fluctuating left sided hearing loss. Audiometry showed fluctuating sensorineural hearing loss of the left ear. As numerous attempts with medication failed to control vertigo, and since vertiginous attacks occurred weekly, vestibular nerve section was performed. Intraoperative monitoring of ABR revealed 0.7 msec elongation of the intervals between waves I and V just after vestibular nerve section. By the end of the operation the amplitude of wave I had decreased. On the other hand, CAP remained stable, and its latency change was minimal. A postoperative audiogram was within the range of her preoperative one for all frequencies. No attacks of vertigo have been experienced postoperatively. The second patient, a 50-year-old man, had a 13-year history of episodic vertigo. His audiogram showed a flat type of sensorineural hearing loss of the left ear. Vestibular nerve section was performed because of his request of prompt relief of vertigo. There was no significant change of wave V after the vestibular nerve section, although other waves remained undetectable during surgery. CAP showed 0.13-0.34 msec elongation of the latencies of waves after the vestibular nerve section. His postoperative audiogram was similar to the preoperative one and there have been no attacks of vertigo. The results indicate that good control of vertigo was obtained and hearing was maintained with vestibular nerve section. CAP is useful in monitoring cochlear nerve function during surgery. © 1989, The Society of Practical Otolaryngology. All rights reserved.