对侧抑制对噪声暴露后的瞬态诱发耳声发射的影响

目的 :了解对侧抑制对噪声暴露前后瞬态耳声发射 (TEOAE)的影响。方法 :观察对侧抑制 (6 0dBSPL宽带噪声 )对噪声暴露前后TEOAE反应幅值、波重复率、频带信噪比、频带重复率等指标的变化。结果 :短时噪声暴露后 ,TEOAE各指标的数值都有所下降 ,敏感地反映出噪声暴露对耳蜗功能的影响。对侧抑制在噪声暴露前可引起较小的下降 ,部分指标有显著性改变。暴露后 ,对侧抑制使TEOAE指标下降更明显。结论 :噪声暴露可对耳蜗功能状态产生明显影响 ,降低耳声发射的测值。对侧抑制对耳蜗进行负反馈调节 ,可明显提高TEOAE测试检出噪声暴露所引起改变的敏感度。

A study on the effects of contralateral acoustic suppression to transient evoked otoacoustic emissions after noise exposure

Objective:To investigate the effects of contralateral acoustic suppression(CAS) on transient evoked otoacoustic emissions(TEOAE) in Noise Exposure Condition, in order to explore the effects of efferent positive feedback regulation on the cochlear mechanisms and the effects of CAS on the sensitivity of TEOAE measure for finding changes of cochlear function condition induced by noise exposure.Methold: Observing the effects of CAS (60 dB SPL WN) on the changes of TEOAE parameters, Response Amplitude, Reproducibility, Band SNR and Band Reproducibility, before and after noise exposure.Result:The values of every index of TEOAE were decreased respectively so that the effects of noise exposure on cochlear function can be reflected sensitively. A small decrease of values can be induced by CAS before noise exposure, of some decrease of indices were significant. After noise exposure, the changes of TEOAE parameters become much more with CAS than without.Conclusion:Noise exposure can effect obviously cochlear function condition and decrease OAE measurement values. CAS had suppressing action on cochlear activity by a negative feedback and can incease obviously the sensitivity of TEOAE measurement in finding the changes induced by noise exposure.