骨导听觉脑干电反应测试中掩蔽噪声的应用

目的探讨骨导听觉脑干电反应（ａｕｄｉｔｏｒｙ ｂｒａｉｎｓｔｅｍ ｒｅｓｏｎｓｅ，ＡＢＲ）测试中对侧耳适宜的掩蔽强度。方法对１６例正常受试者进行骨导ＡＢＲ检测及观察刺激侧和对侧白噪声掩蔽对其波形的影响，并对一耳听力正常、另一耳重度感音神经性聋的５位患者进行验证。结果正常人当同侧或对侧耳加以白噪声掩蔽时，骨导ＡＢＲ波形和Ｖ波潜伏期与未加掩蔽时不同。在单侧感音神经性聋患者，患者给予６０ｄＢ骨导刺激诱发

Application of Masking Noise in Bone- Conducted Auditory Brainstem Response

Objective This experiment was designed to investigate the optimal masking noise on the contralateral ear in the measurement of auditory brainstem responses evoked by bone-conducted acoustic stimulations. Methods The air-conducted ABR and the bone-conducted ABR were measured in 16 persons with normal hearing and 5 patients with unilateral profound sensorineural hearing loss to observe the influence of ipsilateral and contralateral masking on the bone-conducted ABR. Results The waveform of bone-conducted ABR was the same as that of air-conducted ABR, but the response threshold of wave V in the former was higher than that in the latter and the latency of wave V in the former was longer than that in the latter. The waveform and latency of wave V in bone-conducted ABR varied when masking (white noise) was applied on the ipsilateral or contralateral ear. Conclu sion The waveform of bone-conducted ABR was stable as air-conducted ABR. Excitation in both cochleae could be caused by bone-conducted acoustic stimulation on one ear, and the ABRs from both cochleae were evoked. Therefore, it is necessory to mask the contralateral ear while testing bone-conducted ABR. The intensity of 20dB less than that of bone-conducted stimulation may be the most suitable if white noise is selected as masking noise.