听觉脑干反应相位谱分析客观诊断中高频听力损失

Phase spectral analysis of auditory brainstem responses for the objective diagnosis of hearing loss at middle and/or high frequencies

采用Fridman提出的相位谱分析方法——同步度（SM）测试法，对40dBnHL短声诱发的正常耳听觉脑干反应（ABR）进行相位谱构型分析。40耳统计表明，ABR相位谱主要包含4个频域成分，即A：0～160Hz、B：160～440Hz、C：440～930Hz和D：930～1370Hz，以各成分谱参量——SM的平均值和标准差的差值作为鉴别中高频听力损失的标准值。对测试组各聋耳（49耳）40dBnHL短声诱发ABR进行相位谱构型分析，计算上述各主要相位谱成分的SM值，并同相应成分的标准值进行比较，以判定中高频性耳聋。各谱成分对测试耳的正确诊断丰分别为A：59．2％、B：51．0％、C：95．9％和D：44．9％。结果表明，C成分是ABR相位谱的唯一特征成分，其SM值能有效确定中高频听力损失，可作为客观诊断中高频性耳聋的临床指标。

The synchrony measure (SM) method, a phase spectral analysis described by Frid-man, was applied to pattern analysis of auditory brainstern responses (ABRs) elicited byclicks at the stimulus intensity of 40 dB nHL in 40 normal ears. The phase spectra ofnormal ABRs were composed mainly of four frequency components at 0 to 160Hz, 160 to440 Hz, 440 to 930Hz, and 930 to 1 370 Hz, named component A, B, C and D, respec-tively. Based on the mean-1SD of the SM of each component above, which was adoptedfor the detection of hearing loss at middle and/or high frequencies, the SM method wasused to analyze ABRs elicited with 4O dB nHL clicks in the testing gruop including 49deaf ears. The correct diagnostic percentages were 59- 2%, 51.0%, 95.9%, and44.9% for the criterion of component A, B, C, and D, respectively. The results indi-cate that cornponent C is the only effective component of ABRs f and has significant clin-ical value in the objective diagnosis of hearing loss at middle and/or high frequencies.