Clinical application of transiently evoked otoacoustic emissions after glycerol administration for diagnosis of sensorineural hearing loss

Pure-tone audiometry and transiently evoked otoacoustic emission (TEOAE) measurements were made before and after glycerol administration in the ears of sensorineural hearing loss with three different clinical entities, i.e. Meniereʹs disease, cochlear Meniereʹs disease and unilateral sensorineural hearing loss of unknown cause without hearing fluctuation (SNHLWF). TEOAE was evoked after glycerol administration in several ears of Meniereʹs disease and cochlear Meniereʹs disease, in which it was not evoked before glycerol administration. Especially in patients with cochlear Meniereʹs disease, TEOAE was altered without an accompanying significant change in mean hearing level. The change in TEOAE after glycerol administration indicates that the active motile property of outer hair cells may be affected by endolymphatic hydrops