Effects of overpressure on hearing function in Menière's disease.

The relationship between ambient pressure changes and hearing function was investigated in 14 patients with well-defined sensorineural hearing losses caused by Meniere's disease. The period of exposure to pressure changes varied individually between one and 4 months. The evaluation of hearing function was made by means of pure-tone audiometry, speech discrimination tests and psychoacoustic measurements of the inner ear frequency selectivity. Significant changes were found in the hearing parameters in relation to the period of pressure application. The use of psychoacoustic tuning curves allowed spatial observations on changes in the frequency selectivity. This method proved to be of particular value in the assessment of the inner ear function in Meniere's disease. The results support the hypothesis that the use of overpressure creates a change in the hydrodynamic properties of the cochlea, reflected in an improvement of the inner ear frequency analysis.