听性脑干反应的相位谱分析和阈值测定

Phase Spectral Analysis of Auditory Brainstem Response and Threshold Detection

目的 证实相位谱分析方法———以同步度 (SM)为指标测定听性脑干反应 (ABR)阈值的实用性。方法 基于对正常组 ( 40耳 ) 30dB短声诱发ABR相位谱所解析出的有效傅里叶成分 10 0～ 1170Hz ,并根据Fridman建立的阳性诱发反应阈值判断公式SM >SM +ZPσsm,计算出SM阈值标准为 0 .13,进而应用于受试组 ( 46耳 )ABR的谱分析及阈值测试 ,同时与ABR时域分析阈值进行比较。结果 受试耳中 ,谱分析和时域分析阈值相同的有 32耳 ,谱分析阈值高于和低于时域分析阈值分别有 8耳和 6耳 (相差均不超过 10dB) ,两者之间统计分析 :配对t检验 ,无显著性差异 ;相关分析 ,高度相关。

Objective To confirm the utility of the phase spectral analysis developed by Fridman,known as the synchrony measure(SM) method,for objective detection of auditory brainstem response(ABR)thresholds.Methods A criterion for the presence of a response was SM>SM+Z Pσ sm .In this study,the threshold criterion was 0.13,as calculated from the efficient Fourier components at 100 to 1 170 Hz of ABR elicited with 30 dB nHL clicks in a normal group of totally 40 ears.On the basis of the above criterion,ABR thresholds were detected by the phase spectral analysis in a experimental group including 46 ears.The results were compared with the thresholds visually determined on the waveforms of ABR for the same individuals.Results Response thresholds obtained by the phase spectral analysis were the same as those by visual analysis in 32 out of the 46 ears,while the former values were 10 dB higher in 8 ears and 10 dB lower in 6 ears.Highly significant correlation and no significant differences were seen between findings of these two methods by statistical analysis.Conclusion The phase spectral analysis is an useful tool for objective detection of ABR thresholds.