骨导短声诱发听性脑干反应在外耳道闭锁患儿听力评估中的应用

Application of auditory brainstem responses to bone-conducted clicks in the hearing assessment of children with congenital external aural atresia

目的:探讨骨导短声诱发听性脑干反应(ABR)在先天性外耳道闭锁患儿听力评估中的应用价值。方法:采用病例对照研究,2008-01~2014-04我院诊治的先天性外耳道闭锁患儿15例(19耳)为病例组;正常听力小儿16例(32耳)为对照组,均行气导和骨导ABR测试。比较两组小儿气、骨导ABR波形特点、反应阈值、Ⅴ潜伏期等指标。结果:正常听力小儿气、骨导ABR波形相似,在其最大输出强度下仅引出明显的Ⅰ波、Ⅲ波和Ⅴ波。外耳道闭锁患儿气导ABR在最大输出强度下能引出明显的Ⅰ~Ⅴ波,骨导ABR波形与正常小儿相似。外耳道闭锁组患儿气导ABR反应阈值、气骨导阈值差值高于正常组小儿,差异均有统计学意义(P<0.05),而两组小儿骨导ABR反应阈值无统计学差异(P>0.05)。结论:骨导ABR不受外耳和中耳病变的影响,反映内耳功能,并且气、骨导ABR阈值差值可以辨别先天性外耳道闭锁患儿听力损害的类型。

Objective:To evaluate the auditory brainstem responses(ABR)to bone-conducted clicks in the hearing assessment of children with congenital external aural atresia.Methods:Fifteen children with congenital external aural atresia(19ears)from 2008 to 2014were included in the study,and 16 healthy children(32ears)were used as normal controls.All children were examined by both of ABR to airconducted clicks and bone-conducted clicks.The parameters including ABR waves,ABR thresholds,latency of waveⅤ were recorded and compared between two groups.Results:Healthy children had similar ABR waves in air and bone conduction,in which wave Ⅰ,wave Ⅲ,and waveⅤwere induced obviously at maximal stimulus.The children with external aural atresia had similar ABR waves with the healthy children in bone conduction tests,but they wave induced obvious waves from ⅠtoⅤin air conduction tests.The ABR thresholds to air conducted clicks and the threshold difference between air and bone conduction tests was significantly higher in the children with atresia than those in healthy children(P <0.05).No significant difference of ABR thresholds to bone conducted clicks was found between two groups(P >0.05).Conclusion:The inner ear function can be reflected by bone-conducted ABR,the threshold difference between air conducted and bone conducted tests can be used to differentiate the hearing injury type for external aural atresia.