A Case of Fluctuating Hearing Loss

Abstract

A 44-year-old woman who had fluctuating sensoryneural hypoacusis in her left ear without vertigo was reported.
The hearing loss fluctuated beetween 40 and 60dB in all frequencies during about 1 year. Audiometric evaluations revealed that the lesion of this hearing impairment might be in the inner ear. Transtympanic electrocochleographies (ECochG) were performed both at the early stage and at 8 months after the onset when the hearing loss was fixed at 40dB. At the early stage, the prolongation of N₁-latency, increasing of SP/AP ratio and a wide N₁ waveform were observed in ECochG. These findings which were commonly observed in Ménière's disease induced a conclusion that insufficiency of the stria vascularis and endolymphatic hydrops mentioned earlier by Williams, resulted in a reversible fluctuating hearing loss.