Boys Town National Research Hospital, 555 North 30th Street, Omaha, Nebraska 68131, USA.
National Center for Rehabilitative Auditory Research, VA Portland Health Care System, 3710 Southwest U.S. Veterans Hospital Road, Portland, Oregon 97239, USA.
J Acoust Soc Am. 2018 Jan;143(1):399. doi: 10.1121/1.5021252.
Transient-evoked otoacoustic emission (TEOAE) responses were measured in normal-hearing adult ears over frequencies from 0.7 to 8 kHz, and analyzed with reflectance/admittance data to measure absorbed sound power and the tympanometric peak pressure (TPP). The mean TPP was close to ambient. TEOAEs were measured in the ear canal at ambient pressure, TPP, and fixed air pressures from 150 to -200 daPa. Both click and chirp stimuli were used to elicit TEOAEs, in which the incident sound pressure level was constant across frequency. TEOAE levels were similar at ambient and TPP, and for frequencies from 0.7 to 2.8 kHz decreased with increasing positive and negative pressures. At 4-8 kHz, TEOAE levels were larger at positive pressures. This asymmetry is possibly related to changes in mechanical transmission through the ossicular chain. The mean TEOAE group delay did not change with pressure, although small changes were observed in the mean instantaneous frequency and group spread. Chirp TEOAEs measured in an adult ear with Eustachian tube dysfunction and TPP of -165 daPa were more robust at TPP than at ambient. Overall, results demonstrate the feasibility and clinical potential of measuring TEOAEs at fixed pressures in the ear canal, which provide additional information relative to TEOAEs measured at ambient pressure.
瞬态诱发耳声发射（TEOAE）响应在正常听力成人耳朵中进行测量，频率范围从 0.7 到 8 kHz，并结合反射/导纳数据进行分析，以测量吸收声功率和鼓膜峰值压力（TPP）。平均 TPP 接近环境压力。TEOAE 在耳道中进行测量，环境压力、TPP 和从 150 到-200 达帕的固定气压。使用 click 和 chirp 刺激来引出 TEOAE，其中入射声压级在整个频率范围内保持不变。在环境压力和 TPP 下，TEOAE 水平相似，对于 0.7 到 2.8 kHz 的频率，随着正压和负压的增加而降低。在 4-8 kHz 时，正压下 TEOAE 水平更大。这种不对称性可能与中耳链机械传递的变化有关。平均 TEOAE 群延迟不随压力变化，尽管在平均瞬时频率和群延迟扩展方面观察到了一些小的变化。在咽鼓管功能障碍和 TPP 为-165 达帕的成人耳朵中测量的 chirp TEOAE 在 TPP 下比在环境压力下更稳定。总体而言，结果表明在耳道中固定压力下测量 TEOAE 的可行性和临床潜力，这与在环境压力下测量的 TEOAE 相比提供了额外的信息。
