应用40Hz听觉相关电位与听性脑干反应评估听阈

对 42例 74耳（正常听力组 32耳,检案中主诉听力下降 42耳）分别进行纯音测定,声导抗测定,听性脑干反应 (Auditory Brainstem Response,ABR)及 0.5～ 2kHz范围的 40Hz听觉相关电位 (40Hertz Auditory Event－ related Potential,40Hz AERP)测定,对其中 20耳进行睡眠及清醒两种状态的 40Hz AERP测定。将纯音听阈、 40Hz AERP反应阈、 ABR反应阈三者之间进行比较分析。结果表明,正常听力耳 40Hz AERP反应阈值较纯音测听阈值高,在不同频率的校正值 (差值 )不同, 0.5 kHz为 12.7± 6.4(dBnHL); 1kHz为 14.7± 6.3(dBnHL); 2 kHz为 15± 5.6(dBnHL)。 ABR阈值比行为听阈高,校正值为 8.9± 5.3(dBnHL)。睡眠状态时 40Hz AERP阈值较清醒状态阈值高,校正值为 9.7± 2.45(dBnHL)。检案中主诉听力下降者主、客观语音频率均值之间明显不相符 ,误差率为 61％。本研究表明单纯使用 ABR、纯音测听中任何一种方法估计语音频率听阈均有一定的误差。

Evaluation of hearing thresholds of 40Hz auditory event related potential and auditory brainstem response

Recordings of pure tone response, 40 Hz auditory event-related potential (40 Hz AERP) and auditory brainstem response (ABR) were obtained for 74 ears of 42 cases (32 normal ears, 42 injured ears). 40 Hz AERP (0.5-2 kHz) of 20 ears was tested under natural sleep and awake conditions. The results showed that the threshold of 40 Hz AERP was higher than that of tone pip, with the difference of 12.7 +/- 6.4 dBnHL at 0.5 kHz, 14.7 +/- 6.3 dBnHL at 1 kHz, and 15.6 +/- 5.6 dBnHL at 2 kHz respectively. The threshold of 40 Hz AERP increased in natural sleep compared with that in awake state. The threshold of ABR was higher than the behavioral. The data suggests that jointly using several tests get more accurate and objective results in evaluating hearing loss.