正常气骨导听性脑干反应及其应用

Study on auditory brainstem response

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ABRⅤ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。

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（ Ⅴ waves）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 wave Ⅴ latency-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 boneconducted 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.