Audiogram Fine Structure and Spontaneous Otoacoustic Emissions in Patients with Meniere's Disease

Abstract

The incidence of and inter-relationship between audiogram fine structure and spontaneous otoacoustic emissions (SOAEs) was investigated in patients with Meniere's disease. This project is a part of a comprehensive longitudinal study in which a range of tests of cochlear and vestibular function in patients who suffer from Meniere's disease, is carried out and repeated over time. In this paper we present preliminary data from both ears (in most cases an affected and an unaffected ear) of 13 patients. The thresholds in these 26 ears ranged from normal to 80 dB HL. SOAEs could be measured in only four ears; these ears had near-normal thresholds. Data from seven ears had to be excluded because of the possibility of cross-over effects. In 16 out of the 19 remaining ears, audiogram fine structure was found. Our data confirm that

(1) SOAEs correspond to behavioural sensitivity peaks.

(2) There is no simple relationship between SOAE level and height of sensitivity peaks.

(3) Sensitivity peaks may occur at frequencies without measurable SOAEs. In addition, our data show that:

(1) Audiogram fine structure may occur in ears without observable SOAEs.

(2) Fine structure can be present in ears without normal thresholds.

(3) There is a weak tendency for fine structure to be more pronounced in ears with milder hearing loss.

Key Words:

• Audiogram fine structure
• Spontaneous otoacoustic emissions
• Meniere's disease