婴幼儿听神经病的听力学特点

The audiological clinical features on infants with auditory neuropathy

目的通过分析7例(14耳)听神经病患儿的听力测试结果,探讨婴幼儿听神经病听力学特点。方法对5例(10耳)瞬态耳声发射(Transient evoked Otoacoustic Emission TEOAE)筛查通过但对声音反应差患儿和2例(4耳)听觉脑干诱发电位(Auditory brain stemresponse ABR)筛查40dB nHL未通过患儿行声导抗、畸变产物耳声发射(distortion product otoacoustic e-mission DPOAE)、ABR、听觉稳态诱发电位(auditory steady state response ASSR)检查,记录并分析结果。结果所有患儿声导抗均呈A型,镫骨肌反射未引出;DPOAE正常;14耳ABR均未见分化的Ⅱ波及以后波形,仅1例1耳于90dB nHL见分化的Ⅰ波;听觉稳态诱发电位0.5～4kHz听阈介于65～90dBHL,表现为中至重度听力损失,与ABR听阈严重不符。结论耳声发射正常伴异常的听觉稳态和听觉脑干诱发电位及其反应阈之间的严重不一致性,是听神经病较为显著的听力学特点,可应用于婴幼儿听神经病的早期诊断。

Objective To study the hearing test data of 7 infants with auditory neuropathy and explore the audiological clinical feature. Methods 5 infants who had past the hearing screen with the teoae but had bad response to voice and 2 infants who had fallen the hearing screen with the ABR were all diagnosed respectively by acoustic immittance, ASSR, ABR and DPOAE. The audiometric testing data were recorded and anlysised. Results It indicated that all the cases＇ had normal DPOAE and cochleostapedial reflex were disappeared; Ⅰ to Ⅴ waves disappeared excepet that 1 case cluld make out the Ⅰ wave with ABR;ASSR thresholds were between 50dB HL and 90dB HL and indicated it was moderate to severe hearing lose, which were lower than ABR thresholds. Conclusion Normal DPOA and the discrepancy between ASSR and ABR threshold are audiometric feature of AN.