Abstract
Otoacoustic emission (OAE) has the property for personal biometric identification. It can be measured in human's ear anytime, anywhere, and similar results can be got from the same ear. In the past, OAE usually measured at audiometer testing room and rather stable results would be obtained. In this study, we developed a system for transient evoked otoacoustic emission (TEOAE) measurement for the patients of Ménière disease (MD) at the hospital. TEOAE data were measured in a normal room, and the signal-to-noise ratio was 13.72 dB SPL in average. After giving an acoustic impulse, OAE components occur sequentially from higher to lower frequencies; for example, the delay time of the 1 kHz, 2 kHz and 4 kHz components are 11 ms, 7.1 ms and 4.6 ms, respectively. To find the relation between TEOAE and disease, we compared the data with patient's pure tone audiometry (PTA) and distortion product otoacoustic emissions (DPOAEs). We cooperated with Cathay general hospital and collected 23 MD patients with different illness degrees: certain, possible, probable, stage I, stage II and stage III. Totally, 78 cases of MD ears, 129 cases of non-MD ears and 18 cases of normal hearing ears were recorded. For objects with hearing loss, which means the PTA is greater than 25 dB SPL, the energy of both TEOAE and DPOAE is less than that for normal hearing objects. If the PTA is over 40 dB SPL, almost no OAE signal can be found in those cases. For those MD objects with normal hearing or mild hearing loss, the energy of TEOAE is 3.86 × 10 ^(-10) Pa ^2 in average and is still weaker than that for health hearing objects, which is 1.33 × 10 ^(-9) Pa ^2 in average.