[Study on auditory brainstem response to bone conducted clicks].
OBJECTIVE: To observe how different vibrator placement and different stimulate rates affect the results of bone conduction ABRs. METHOD: Bone conduction ABRs with different vibratory placement and different stimulate rates were recorded in 20 normal hearing young adults and compared with their air conduction ABRs. RESULT: The results show that all subjects were recorded reproducible and reliable air and bone conduction ABR waveforms under higher intensities(above 40 dBnHL). The ABR thresholds from air and bone conduction were similar, they are both about 5-10 dB higher above their behavioral thresholds to clicks. The frontal placement produces significantly longer ABR wave V latencies. Bone conduction ABR wave V latencies from different stimulate rates were also observed. The results show that temporal placement ABR wave V latencies became longer significantly when the stimulate rate increased from 20/s to 52/s. CONCLUSION: Although it is affected by different vibrator placement and different stimulate rate, bone conduction ABR is a valuable and effective method to detect hearing, it plays an important role in newborn auditory screening, assessment of cochlear reserve, and identification of hearing loss.