Chida E
Department of Otolaryngology, Hokkaido University School of Medicine, Sapporo.
Nihon Jibiinkoka Gakkai Kaiho. 1998 Nov;101(11):1335-47. doi: 10.3950/jibiinkoka.101.11_1335.
Distortion product otoacoustic emissions (DPOAEs) were evaluated in 494 normal and 506 cochlear-impaired human ears, to determine whether DPOAEs depend on factors such as background noise, the shape of the pure tone audiogram, sex and aging, and whether a DPOAE test can perform well in distinguishing normal-hearing from hearing-impaired ears. The amplitudes of DPOAEs were measured at the frequency of 2f1-f2 (f1 < f2, f2/f1 = 1.22, f2 at 1, 2 and 4 kHz) using as stimuli two pure tones at level of 70 dB from an ILO92 Otoacoustic Emission Analyzer. The correlation coefficients between the DPOAE level and the auditory threshold decreased as the background noise levels at 1 kHz and 2 kHz increased. Therefore, it appeared that ears with large background noise levels would be inadequate for the study of DPOAEs predicting the hearing state. The sensitivity (normal-hearing ears identified as normal hearing) and the specificity (hearing-impaired ears identified as hearing impaired) at the equal-sensitivity-specificity condition were 80.7-86.7% at 1, 2 and 4 kHz, and the areas under the receiver operating characteristic (ROC) curves, which were used to estimate the test performance, were 0.88 for 1 kHz, 0.91 for 2 kHz and 0.92 for 4 kHz. Since these results suggest that a DPOAE can be used as a reliable technique for objective auditory tests, it is thought that actual values (DPOAE level: 4.3 dB at 1 kHz, 5.0 dB at 2 kHz and 2.9 dB at 4 kHz) of false-positive (hearing-impaired ears identified as normal hearing) rates corresponding to 5% can be used in clinical evaluation to separate normal hearing from hearing-impaired ears. There was, however, a significant age effect at 4 kHz on DPOAEs in the ears with the same pure tone hearing thresholds, and the areas of the ROC curves in subjects ranging from 10 to 29 years old were larger than in subjects over 50 years (1 kHz: 0.88 to 0.94 versus 0.83 to 0.84, 2 kHz: 0.95 versus 0.89, 4 kHz: 0.95 to 0.96 versus 0.88 to 0.89). Therefore, it is thought that age-adjusted norms may be necessary for the accurate interpretation of DPOAE results.
对494只正常耳朵和506只耳蜗受损耳朵进行了畸变产物耳声发射（DPOAE）评估，以确定DPOAE是否依赖于背景噪声、纯音听力图形状、性别和年龄等因素，以及DPOAE测试在区分正常听力和听力受损耳朵方面是否能表现良好。使用ILO92耳声发射分析仪，以70分贝的强度作为刺激，在2f1 - f2频率（f1 < f2，f2/f1 = 1.22，f2分别为1、2和4千赫）测量DPOAE的振幅。随着1千赫和2千赫背景噪声水平的增加，DPOAE水平与听阈之间的相关系数降低。因此，似乎背景噪声水平高的耳朵不适用于研究DPOAE预测听力状态。在等灵敏度 - 特异度条件下，1、2和4千赫时的灵敏度（正常听力耳朵被判定为正常听力）和特异度（听力受损耳朵被判定为听力受损）分别为80.7 - 86.7%，用于评估测试性能的受试者工作特征（ROC）曲线下面积，1千赫时为0.88，2千赫时为0.91，4千赫时为0.92。由于这些结果表明DPOAE可作为客观听力测试的可靠技术，因此认为在临床评估中，对应5%假阳性率（听力受损耳朵被判定为正常听力）的实际值（1千赫时DPOAE水平：4.3分贝，2千赫时为5.0分贝，4千赫时为2.9分贝）可用于区分正常听力和听力受损耳朵。然而，在4千赫时，对于纯音听阈相同的耳朵，年龄对DPOAE有显著影响，10至29岁受试者的ROC曲线面积大于50岁以上受试者（1千赫：0.88至0.94对0.83至0.84，2千赫：0.95对0.89，4千赫：0.95至0.96对0.88至0.89）。因此，认为可能需要年龄校正标准来准确解读DPOAE结果。
