Standardization of latency and amplitude parameters on brainstem auditory evoked potential recording with narrow band Ichirp stimulus in normal hearing adults

ABSTRACT

Purpose

Standardize the latency and amplitude parameters using the narrow band Ichirp stimulus on Brainstem Auditory Evoked Potential (BAEP) at frequencies of 500 Hz, 1 kHz, 2 kHz and 4 kHz.

Methods

The study was performed at the Hospital for Rehabilitation of Craniofacial Anomalies (HRAC), Auditory Health Division, University of São Paulo (USP). Twenty normal hearing adults, aged between 18 and 35 years, were submitted to pure tone audiometry, speech audiometry, immittance and to BAEP with narrow band Ichirp stimulus at 500 Hz, 1 kHz, 2 kHz and 4 kHz frequencies.

Results

In all frequencies evaluated, the latency-intensity function was observed, that is, the increase in the latency of the V wave as the stimulus intensity was decreased, as well as the decrease in the latency of the V wave with the increase of the frequency. In addition, the reduction in the amplitude of the wave V was verified with the decrease of the intensity of the stimulus. The minimum response level, in all frequencies, was found to be lower than the values suggested in the literature as a criterion of normality in frequency - specific BAEP, with the highest values at frequencies of 500 Hz and 1 kHz.

Conclusion

Normal reference values to BAEP were obtained in normal hearing adults with the narrow band Ichirp stimulus, which may contribute to its improvement in clinical practice.

Keywords:
Brainstem Auditory Evoked Potentials; Electrophysiology; Adult; Hearing; Parameters