听力正常人听性稳态反应阈值与纯音测听阈值的比较

目的 通过比较听性稳态反应（auditory steady-state responses,ASSR）阈值与纯音测听（pure tone audiometry,PTA）阈值,为ASSR技术应用于听力障碍法医学鉴定提供技术数据。建立本实验室ASSR阈值与PTA阈值的校正值。方法 对27例（54耳）正常听力志愿者进行PTA及500、1000、2000和4000Hz的ASSR测试,采用配对t检验法比较测试耳ASSR闽值与PTA阈值的关系;并验证Smart EP-ASSR测试系统校正后的ASSR阈值与PTA阈值的一致性。结果 正常耳ASSR阈值较PTA阈值高（P〈0．05）,各频率差值：500Hz为（22．04±5．79）dB,1000Hz为（11．02±5．44）dB,2000Hz为（12．59±5．89）dB,4000Hz为（17．78±7．25）dB;仪器校正后的ASSR阈值与PTA阈值的差值：500Hz为（-3．96±5．79）dB,1000Hz为（0．02±5．44）dB,2000Hz为（-0．41±5．89）dB,4000Hz为（-1．25±7．25）dB。结论 听力正常人ASSR阈值较盯A阈值高,其差值在各频率不一致．平均为16．9dB。ASSR用于听力障碍法医学鉴定中评估行为听阈时,ASSR阈值需要进行校正。

Comparison of thresholds acquired with ASSR and PTA in normal-hearing subjects

OBJECTIVE: To provide new objective technology in evaluating hearing loss for forensic expert by comparing the thresholds acquired with auditory steady-state responses (ASSR) and pure tone audiometry (PTA) in our laboratory. METHODS: Twenty-seven subjects with normal hearing (54 ears, 18-28years) were tested with PTA and ASSR at 500, 1000, 2000 and 4000 Hz. Paired t-test analysis was performed on threshold of ASSR and PTA at difference frequency (500, 1000, 2000 and 4000 Hz). RESULTS: At each frequency (500, 1000, 2000 and 4000 Hz), the thresholds acquired with ASSR were higher than those acquired with PTA (P<0.05). The mean difference of each frequency were (22.04+/-5.79) dB (500 Hz), (11.02+/-5.44) dB (1000 Hz), (12.59+/-5.89) dB (2000 Hz) and (17.78+/-7.25) dB (4000 Hz). The mean difference between the system automatically adjusted threshold of ASSR and PTA were (-3.96+/-5.79) dB at 500 Hz, (0.02+/-5.44) dB at 1000 Hz, (-0.41+/-5.89) dB at 2000 Hz, and(-1.25+/-7.25) dB at 4000 Hz. CONCLUSION: At each frequency (500, 1000, 2000 and 4000 Hz), the thresholds acquired with ASSR were higher than those acquired with PTA. The mean difference is 16.9 dB. As an objective and mature method, ASSR could be used in evaluation of hearing-loss degree for forensic expert. But adjusted threshold value should be established when ASSR is used to estimate hearing threshold in each laboratory.