Anaoysis of latency and frequency component of evoked otoacoustic emission

诱发耳声发射的潜伏期和频率分量分析

基本信息

批准号：
02670768
负责人：
TAKEDA Taizo
金额：
$ 1.22万
依托单位：
Kochi Medical School
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-02670768/
关键词：
EOAE Meniere's disease Sudden deafness Fast component Slow component Input-output function Nonlinearity Prognosis EOAE Freguency Slow component Fast component

项目摘要

In order to investigate the properties of otoacoustic emissions(EOAEs)in detail, we introduced a new method for frequency analysis of EOAEs, (100 Hz harrow-band EOAEs analysis) : a series of ten echo responses to click stimuli, filtered by a 100 Hz step of pass-band width in the frequencyregions from 1.0 to 2.0 kHz with the use of a dual channel variable filter. In the present study, we investigate the properties of EOAEs from normal ears and from ears with sudden deafness and Meniere's disease. The results were as follows :1)EOAEs from normal ears were composed of two main echo trains and several subechoes. The main echo trains were divided into fast components with short latency below 10 msec and slow components with long latency over 10 msec. The fast component was detected clearly in the higher frequency ranges than 1.5 kHz, the slow component in the lower frequency ranges than 1.4 kHz. Although both fast and slow components showed nonlinear properties, the slow component had a relatively low detection threshold, usually below O dB nHL and saturated around 20 - 30 dB nHL.2)In an early stage of sudden deafness or Meniere's disease, 100 Hz narrow-band EOAEs could often be detected from ears with a severe hearing loss greater than 5O dB HL. But slow component of EOAEs from ears with these lesions was usually small in amplitude or absent, because slow component was more vulnerable than fast component.3)In Meniere's disease or early of sudden deafness, the persistence of slow component indicated a good prognosis of hearing loss.4)Nonlinear property of EOAES, marked in normal ears, was lost in lesioned ears. Therefore, EOAEs could not be detected from a pathologic ears with use of nonlinear click sequence.

为了详细研究耳声发射 (EOAE) 的特性，我们引入了一种新的 EOAE 频率分析方法（100 Hz 耙带 EOAE 分析）：一系列对点击刺激的 10 个回声响应，通过 100 个过滤器进行过滤。使用双通道可变滤波器时，通带宽度在 1.0 至 2.0 kHz 频率区域内的 Hz 步长。在本研究中，我们研究了正常耳朵和突发性耳聋和梅尼埃病耳朵的 EOAE 特性。结果如下：1)正常耳的EOAE由两个主回声序列和多个子回声组成。主要回波序列分为具有低于 10 毫秒的短延迟的快速组件和具有超过 10 毫秒的长延迟的慢速组件。在高于 1.5 kHz 的频率范围内可以清楚地检测到快分量，在低于 1.4 kHz 的频率范围内可以清楚地检测到慢分量。尽管快分量和慢分量都表现出非线性特性，但慢分量的检测阈值相对较低，通常低于O dB nHL，在20 - 30 dB nHL左右饱和。2）在突发性耳聋或梅尼埃病的早期阶段，100 Hz窄带- 频段 EOAE 通常可以从严重听力损失大于 5O dB HL 的耳朵中检测到。但患有这些病变的耳朵的EOAE的慢成分通常幅度较小或不存在，因为慢成分比快成分更容易受到影响。3）在梅尼埃病或突发性耳聋早期，慢成分的持续存在表明听力预后良好4) EOAES 的非线性特性在正常耳朵中很明显，但在受损耳朵中却消失了。因此，使用非线性点击序列无法从病理耳朵中检测到 EOAE。