Effects of cochlear hearing loss on the ABR latencies to clicks and 1000 Hz tone pips.

High-frequency hearing losses can substantially confound the interpretation of click-evoked auditory brainstem responses (ABRs). One method proposed to circumvent the problem is to use frequency-specific tone pips to stimulate equivalent areas on the basilar membrane in normal and pathologic groups, or in both ears of asymmetrically impaired patients. This retrospective study investigated the ABRs to clicks and 1000-Hz tone pips from 90 asymmetrically impaired subjects with cochlear pathology. The 4000 Hz threshold significantly affected the wave V latencies from both clicks and tone pips for the most severely impaired subjects. The wave V latencies were highly correlated between ears for both stimuli, but the correlation was higher with the 1000-Hz tone pips. It was concluded that the use of 1000-Hz tone pips can supplement the interpretation of click-evoked ABRs, particularly in patients whose 2000- and/or 4000-Hz thresholds are worse than 75 dB HL.