[Intra- and intersubject variability of acoustically evoked otoacoustic emissions. I. Transiently evoked otoacoustic...

Acoustically evoked otoacoustic emissions are becoming increasingly significant in the clinical monitoring of cochlear function in adults. Any interpretation of these measurements in a clinical setting must consider their intra- and intersubject variability.

Transiently evoked otoacoustic emission (TEOAE) measurements were performed in 32 normally hearing adults in three weekly test sessions. Each ear was tested twice per session, and the results were statistically analyzed.

All test candidates had measurable TEOAEs. Statistically significant differences in TEOAE amplitudes were neither found between two measurements at the same day, nor at weekly intervals. No statistically significant amplitude differences were found between right and left ear of the same candidate. TEOAE amplitudes in women were always higher than in men with statistically significant differences in the 2, 3, and 4 kHz frequency band.

These results indicate that monitoring of the inner ear status can be reliably performed using TEOAE measurements. Changes in TEOAE amplitudes effectively indicate changes in the cochlear function.