爆震对小型猪皮质听觉诱发电位P1-N1-P2波形特征影响的分析OA

Objective To report time-course changes of cortical auditory evoked potentials(CAEPs)P1-N1-P2 in miniature pigs after blast exposure.Methods Fourteen miniature pigs with normal hearing were randomly assigned to receive blast exposure(n=10)or serve as controls(no blast exposure,n=4).Auditory brainstem response(ABR)thresholds,as well as the latency and amplitude of CAEP P1-N1-P2,were recorded at baseline(before blast exposure)and 1,2,4,and 8 weeks after blast exposure,followed by statistical analysis.Results Hearing loss was induced in 8 pigs in the exposure group.There was no significant difference in baseline ABR thresholds and P1-N1-P2 parameters between the two groups(P>0.05).In the exposure group,ABR thresholds increased by≥40 dB SPL immediately after blast exposure,and remained significantly higher than baseline and the control group by the 8th week(P<0.05)despite partial recovery and a trend to stabilize.There was no significant change in ABR threshold at all times in the control group(P>0.05).CAEP P1-N1-P2 were not detectable immediately after blast exposure,but detectable in all animals 1 week after blast exposure,although with progressive prolongation of latency and decrease in amplitude.CAEP P1-N1-P2 parameters remained unchanged in the control group(P>0.05),significantly different from the exposure group at all time points(P<0.05).Conclusions Blast exposure can cause persistent changes CAEP P1-N1-P2 abnormality in miniature pigs.Despite signs of partial recovery,central auditory system dysfunction persists during the observation period with diminishing trend of continued recovery.