正常气骨导听性脑干反应及其应用

［摘要］目的：研究骨导听性脑干反应(ABR)的波形特点及正常的气、骨导ABR Ⅴ波潜伏期-强度曲线及相应的反应阈值，为临床气导ABR（AC ABR）和骨导ABR(BC ABR)的联合应用提供参考依据。方法：利用Nicolet spirit型诱发电位仪、EAR 3A插入式耳机和Radioear B 71骨振动器对一组听力正常年轻人（男32耳、女24耳）进行短声气骨导ABR测试，并观察对侧给予白噪声掩蔽对BC ABR阈值及潜伏期的影响。结果：气骨导ABR相应强度下波形相似波Ⅴ潜伏期－强度曲线表明，随着刺激强度逐渐减低，潜伏期逐渐延长。骨导Click的潜伏期要比气导Click潜伏期延长的程度大，BC ABR反应阈比气导ABR高。对侧70?dBSPL以下强度宽带噪声的使用对BC ABR阈值及阈上10?dB强度下波Ⅴ潜伏期均无显著影响（P＞0.05）。结论：(1) BC ABR波形特点与相应刺激强度的AC ABR极为相似。BC ABR与AC ABR潜伏期-强度函数曲线可望联合用于传导障碍及其程度的评估；(2) 骨导行为的听阈水平超过40?dBHL时，BC ABR难以引出，对其结果的解释应持慎重态度；(3) 骨导ABR测试时常规加对侧噪声掩蔽，但掩蔽声强度不应超过60?dB。

Study on auditory brainstem response

［ABSTRACT］Objective： To observe normative auditory brainstem response (ABR) latency intensity functions and the threshold and provide reference for combined clinical use of air and bone conducted ABR. Methods: ABR absolute thresholds and latencies(Ⅴwaves)were obtained from 56 ears of 28 young persons with normal hearing using both the EARTONE insert earphone and the Radioear B 71 bone viboratory. Results: The air and bone conducted waveⅤlatency intensity functions exhibited increased latencies as intensity decreased. The bone conducted clicks yielded somewhat longer latencies than the air conducted ones. Conclusions: (1) The waves of air and bone conducted ABR are similar, and more information on ascertaining the presence and magnitude of a conductive hearing loss can be obtained when both air and bone conducted ABR wave V latency intensity functions are administered. (2) When the threshold of bone conducted hearing exceeds approximately to 40 dBHL, no BC ABR responses can be observed. (3) Masking is often necessary when administering bone conducted ABR test, but intensity of masking should not exceed to over 60 dBSPL.