The comparison of auditory behavioral and evoked potential responses (steady state and cortical) in subjects with occupational noise-induced hearing loss

摘要

ObjectiveTo define difference scores between PTA, ASSR and CERA thresholds in subjects with occupational NIHL.Design44 subjects undergoing a medico-legal expert assessment for occupational NIHL and fulfilling criteria of reliability were considered. Assessment included: PTA, 40?Hz binaural multiple ASSR and CERA (1-2-3?kHz).ResultsThe respective average difference scores (ASSR - PTA) for 1, 2 and 3?kHz are 13.01 (SD 10.19) dB, 12.72 (SD 8.81) dB and 10.38 (SD 8.19) dB. The average (CERA - ASSR) difference scores are 1.25 (SD 14.63) dB for 1?kHz (NS), 2.73 (SD 13.03) dB for 2?kHz (NS) and 4.51 (SD 12.18) dB for 3?kHz. The correlation between PTA and ASSR (0.82) is significantly stronger than that between PTA and CERA (0.71). In a given subject, PTA thresholds are nearly always lower (i.e.,better) than ASSR thresholds, whatever the frequency (1-2-3?kHz) and the side (right – left). A significant negative correlation is found between the difference score (ASSR – PTA) and the degree of hearing loss.ConclusionASSR outperforms CERA in a medicolegal context, although overestimating the behavioral thresholds by 10–13?dB.