Auditory Brainstem Response with the iChirp stimuli in the infant's audiological diagnosis

Abstract

Objective: to investigate the use of the iChirp stimulus in the infant's audiological diagnosis compared to stimuli typically used in the ABR in infants, in addition to suggesting reference values for the assessment of this population.

Methods: 62 infants participated in the study, 29 females and 33 males. The subjects underwent the recording of the Auditory Brainstem Response in the Smart Ep equipment, with the stimuli click, iChirp-broadband, tone burst and iChirp-narrowband, which were presented at three levels of intensity (20 dB, 40 dB and 60 dB) and, for tone burst and iChirp-narrowband stimuli, at different frequencies (0.5, 1 k, 2 k and 4 KHz). The data were later analyzed using Student's t-test.

Results: In general, the iChirp-broadband and iChirp-narrowband stimuli showed higher latency values and greater amplitudes when compared to click and tone burst stimuli. Furthermore, better signal-to-noise ratios were observed when contrasting iChirp-narrowband with tone burst. Additionally, reference values were established for the assessment of ABR in infants with the iChirp-broadband and iChirp-narrowband in the Smart-Ep equipment.

Conclusion: The iChirp stimulus appears to be promising in the infant's audiological diagnosis, as its use promoted greater amplitudes and better wave morphology, which facilitates to mark the waveforms and provides greater efficiency in the investigation of the auditory thresholds. The indication of normative data also enables the clinical use of these stimuli in the infant's audiological diagnosis.

Keywords: Auditory evoked potentials; Electrophysiology; Hearing; Infants.