Neurophysiologic assessment of endolymphatic hydrops.

An electrophysiological method for assessing endolymphatic hydrops of the cochlea in an animal model of Meniere's disease is described. Eighth nerve gross action potentials (AP) were evoked by tone bursts presented at discrete phases of a simultaneously delivered 50-Hz pure tone. Hydropic cochleas showed significantly less modulation of AP amplitude and latency than normal cochleas. This method may be useful in objectively evaluating Meniere's disease with electrocochleography.