Comparison of Click and Level-Specific CE Chirp-Stimulated Auditory Brainstem Responses in Adults with Hearing Loss.

Background:  The Claus Elberling Chirp (CE-Chirp) stimulus used in the auditory brainstem responses (ABRs) was developed to compensate for the cochlear wave delay. As a version of broadband CE-Chirp stimulus, the use of level-specific (LS) CE-Chirp stimuli, which are created with varying delay models suitable for the intensity levels at which the sound is transmitted, is becoming increasingly common.

Purpose:  The aim of this study was to compare click ABRs with LS CE-Chirp ABR thresholds in adults with sensorineural hearing loss.

Research design:  The research is a cross-sectional, analytical research.

Study sample:  Twenty-two adult patients (n = 44 ears) with bilateral sensorineural hearing loss were included in the study.

Data collection and analysis:  Pure-tone audiometry, click ABR, and LS CE-Chirp ABR tests were performed on adult (13 males and 9 females; 42.86 ± 14.50 years) patients with bilateral sensorineural hearing loss. Click ABR and LS CE-Chirp ABR thresholds were compared in terms of proximity to behavioral hearing thresholds of 2 kHz, 4 kHz, and 2 to 4 kHz averages.

Results:  Both types of ABR stimuli were able to identify with total hearing loss (n = 6). A significant difference was found between LS CE-Chirp ABR thresholds (53.81 ± 20.28 decibel normal hearing level [dB nHL]) and click ABR thresholds (58.81 ± 19.11 dB nHL) in the other ears (n = 38) with hearing loss (p = 0.00). When both ears were evaluated together and the right and left ears were evaluated separately, no difference was found between LS CE-Chirp ABR thresholds and 4 kHz hearing thresholds (p = 0.66, 0.80, and 0.69, respectively).

Conclusion:  In adults with hearing loss, the LS CE-Chirp provides ABR thresholds closer to the behavioral hearing thresholds at 2 and 4 kHz compared with the click stimulus. Notably, there was no difference between LS CE-Chirp ABR thresholds and the 4 kHz behavioral hearing thresholds. We concluded that the LS CE-Chirp can be used effectively in the estimation of behavioral hearing thresholds in adults with hearing loss.