Thresholds of tone burst auditory brainstem responses for infants and young children with normal hearing in Taiwan.

ABSTRACT

BACKGROUND/PURPOSE: With respect to follow-up from newborn hearing screening, click evoked auditory brainstem response provides relatively accurate estimates of auditory thresholds at a broad frequency range between 1,000 Hz and 4,000 Hz. Further on the frequency-specific hearing evaluation, recent studies conclude that tone burst auditory brainstem response estimates the behavioral thresholds reasonably well. This study reports the preliminary data of tone burst auditory brainstem response measurements of infants and young children with normal hearing in Taiwan. METHODS: Ninety-four infants and young children aged from 3 months to 3 years of age were recruited as they were eventually determined to have normal hearing after a series of tests. They underwent tone burst auditory brainstem response measurements at four selected frequencies. Statistical methods were applied to study the relationship among recorded variables. RESULTS: The results indicated that the averaged tone burst auditory brainstem response thresholds of infants and young children with normal hearing in Taiwan are typically 10-20 dB nHL at 500, 1,000, 2,000, and 4,000 Hz, which is similar to the reported tone burst auditory brainstem response thresholds in adults with normal hearing. There was no statistically significant difference for the thresholds with regard to gender, laterality, and age distribution in this study. CONCLUSION: Based on the published research and our study, we suggest setting the normal criterion levels for infants and young children in Taiwan of the tone burst auditory brainstem response to air-conducted tones as 30 dB nHL for 500 and 1,000 Hz, and 25 dB nHL for 2,000 and 4,000 Hz.