[The relations between otoacoustic emissions and pure tone threshold].

Objective: To investigate the relationship between passing rate of otoacoustic emission (OAE) and pure tone thresholds.
Method: OAE including both transient evoked otoacoustic emission (TEOAE) and distortion products otoacoustic emission (DPOAE) as well as pure tone thresholds were measured in subjects with normal hearing and sensory hearing loss. The passing rates of OAE were calculated in subjects with different age groups and different pure tone thresholds.
Result: TEOAE can identify hearing loss at frequencies of 2 kHz and below. For TEOAE and 2 kHz DPOAE, passing rate has no difference between different age groups. For 4 kHz DPOAE, the passing rate in age over 50 years group is lower than other groups. The passing rate decreased as the pure tone threshold increased. When TEOAE and DPOAE suggest " pass", 70%, 81%, 79% subjects had pure tone threshold lower than 25 dB HL and 94%, 96%, 93% lower than 40 dB HL respectively. When they suggest "refer", 93%, 84%, 87% subjects had pure tone threshold higher than 25 dB HL and 71%, 58%, 68% higher than 40 dB HL respectively.
Conclusion: TEOAE is sensitive to hearing loss at middle and low frequencies but not at high frequencies. Measuring both TEOAE and DPOAE might provide more information of hearing loss at 0.5, 1.0, 2.0 and 4.0 kHz. It is worth noting that even OAE suggest "pass" or "refer", because there is still exist the possibility of hearing loss.