Effect of chronic suppurative otitis media on distortion product otoacoustic emission input-output functions in conventional and ultra-high frequencies.

Abstract

BACKGROUND Detection and valid measurements of distortion product otoacoustic emissions are not influenced by cochlear status alone, but also by middle-ear status. There is a need to understand the use of ultra-high frequency distortion product otoacoustic emissions in cases of abnormal distortion product otoacoustic emission findings for conventional frequencies related to the middle-ear condition. METHOD The present study investigated distortion product otoacoustic emission input-output functions in conventional and ultra-high frequencies in: 37 adults with chronic suppurative otitis media (clinical group) and 37 adults with normal hearing sensitivity (control group). RESULTS There were significant reductions in distortion product otoacoustic emission amplitude and mean signal-to-noise ratio in the clinical group compared to the control group, especially for conventional frequencies. CONCLUSION There was a significant reduction in the rate of ears with measurable distortion product otoacoustic emissions in the clinical group, especially for conventional frequencies. The effect of chronic suppurative otitis media was more pronounced in the conventional frequency range compared to the smaller effect seen in the ultra-high frequency range.