Otoacoustic emissions in central auditory disorders.
Otoacoustic emissions are sounds produced by outer hair cells of cochlea. It is known that they may be useful in assessing hearing loss. The aim of our study was to evaluate their diagnostic capability in separating sensory from neural hearing impairment. Transiently evoked otoacoustic emissions (TOAE) and distortion-product emissions (DP) were measured in 14 patients with sensorineural hearing loss. The results showed DP to be present in 12 patients and in 8 of them TOAE were detected despite the mild to severe hearing loss, thus indicating the lesion should be retrocochlear. The recording of otoacoustic emissions appears to be a technique for precise etiological diagnosis of hearing impairment.