Application value of 40Hz auditory event related potential in hearing assessment in noise-exposed workers / 中国职业医学

ABSTRACT

OBJECTIVE: To evaluate the application value of 40 Hz auditory event related potential(40 Hz AERP) in hearing assessment in workers exposed to noise by observing the consistency between pure tone audiometry(PTA) and 40 Hz AERP. METHODS: A total of 240 ears of 120 workers who exposed to noise with PTA high-frequency hearing threshold > 25 dB were selected as the research subjects using the convenient sampling method. The thresholds of PTA and 40 Hz AERP at different frequencies were investigated. According to the average hearing threshold of PTA language frequency, the workers were divided into normal hearing group and mild-, medium-, medium-severe-, severe-hearing loss groups, and the difference and correlation between the thresholds of 40 Hz auditory potential and PTA were analyzed. RESULTS: The response thresholds of 40 Hz AERP of 0.5, 1.0, 2.0 kHz in ears of normal hearing group, and mild-and moderate-hearing loss groups were higher than the PTA hearing threshold(P<0.01), while the 40 Hz AERP response thresholds of 0.5 kHz in the ears of medium-severe-and severe-hearing loss groups were lower than the hearing thresholds of PTA(P<0.05). The different value of the response threshold of 40 Hz AERP and PTA of 1.0 and 2.0 kHz in ears of normal hearing group was higher than 0.5 kHz(median 25.0 vs 15.0 dBHL, 30.0 vs 15.0 dBHL, P<0.01). Except for 0.5 and 1.0 kHz of mild-hearing loss group, the different value of the response threshold of 40 Hz AERP and PTA in ears of the other hearing loss groups were lower than that of the normal hearing group(P<0.01). The 40 Hz AERP response threshold was frequency-specific and correlated well with PTA at the same frequency. The correlation coefficients of 0.5, 1.0 and 2.0 kHz were 0.744, 0.732 and 0.665 respectively(P<0.01). CONCLUSION: It is feasible to evaluate PTA in noise-exposed workers using 40 Hz AERP response threshold, but the 40 Hz AERP cannot completely replace PTA. The measurement frequency and the degree of hearing loss should be considered simultaneously.