[Evoked otoacoustic emissions and middle ear function]

Transiently evoked otoacustic emissions (TEOAE) recorded in 98 ears were compared depending on the results of tympanometry. The values of middle ear pressure in patients without detectable TEOAE are significantly smaller compared to those of patients with detectable TEOAE. In cases of detectable TEOAE, the amplitudes and frequency components were compared to the results of tympanometry. When maximal compliances are shifted towards negative values of middle ear pressure, the amplitudes of TEOAE are reduced with a loss of low frequency components. Small compliance values result in reduced amplitudes of TEOAE with the loss of low frequency components. By means of cluster analysis in the scatter plot of middle ear compliance and pressure, a classification is obtained separating two groups representing significantly groups of patients with and without detectable TEOAE. Summing up, it must be stated that there is an effect of middle ear function on TEOAE which must be taken into consideration when TEOAE are used in clinical application.