感音神经性聋患儿客观测听评估与特征分析

目的：综合评估低龄感音神经性聋患儿蜗性及蜗后病变的临床听力学特点及其与中枢性神经系统病变的关系；并对比观察不同客观测听技术的特征。方法：选取1998－2000年间资料完整的感音神经性聋患儿共310例（500耳），年龄1个月－6岁，平均年龄24．23个月。根据神经康复科的专科评估，分为伴随中枢神经系统病变听力障碍组和不伴随中枢神经系统病变听力障碍组；前者又根据中枢性病变的病理特征及发病特征分为核黄疸－脑瘫，外部性脑积水和其它中枢性病变3小组。设立同年龄段对照组60例（104耳）。每一组组员同时检测听性脑干反应（auditory brainstem responses,ABR)和畸变产物耳声发射（distortion product otoacoustic emissions,DPOAE)，对此观察不同组别间ABR波V阈值及DPOAE各自的特点，同一组间不同ABR波V阈值耳DPOAE的变化特征。结果：（1）低龄感音神经性聋患儿中伴随有中枢神经系统病变者比例高（41％）。（2）伴随有中枢神经系统病变的患儿中，核黄疸－脑瘫常导致严重的蜗后性听力损失，耳蜗功能也轻度受累；外部性脑积水仅导致轻度蜗后听力损失；其它以大脑皮层受累为主的中枢性病变一般不累及耳蜗功能，（3）蜗性听力损失者，ABR波V阈值达60dB nHL时，DPOAE幅值明显下降，达70dB nHL以上者，DPOAE幅值严重下降或消失。结论：感音神经性聋患儿常伴有中枢性神经系统病变，并表现出听力障碍特征的多样性，因此，在临床上需进行跨学科多手段的综合评估。才能作出客观正确的诊断。

Evaluation of sensorineural hearing loss in childhood]

OBJECTIVE: To explore the clinical and audiological characteristics of sensorineural hearing loss (SHL) with pathological changes both in cochlea and retrocochlear in children and evaluate the relationship between SHL and the lesions in the central nervous system (CNS). METHODS: Three hundred and ten cases (500 ears) of SHL accepted between 1998 and 2000 were studied. The age of patients was ranged from 1 month to 6 years old. According to the evaluation of function of CNS by pediatric neurologist, all cases were divided into two groups: SHL with CNS disease and SHL without CNS disease. Some same age children without hearing loss were subjected as control group. All children were tested using both auditory brainstem responses (ABR) and distortion product otoacoustic emissions (DPOAE). RESULTS: 1. The rate of SHL accompanied with CNS diseases was very high in these children. 2. Patients with kernicterus-cerebral palsy usually had serious hearing loss caused by acoustic nerve lesion at retrocochlear, but their cochlea function was injured slightly. Patients with external hydrocephalus had only slight acoustic nerve lesion at retrocochlear, and patients with other CNS diseases usually had no change for their cochlea function. 3. In the group of SHL caused by cochlea lesion, amplitudes of DPOAE decreased obviously when the threshold of wave V of ABR was up to 60 dB nHL, and amplitudes of DPOAE seriously decreased or disappeared when the threshold of wave V was up to above 70 dB nHL. CONCLUSION: The patients with SHL are usually accompanied with CNS diseases in childhood, and their hearing loss appears very difference from audiological characteristics. We suggest that it is necessary to test both ABR and DPOAE in these patients, and it is important that pediatric neurologist join in audiologist team for our clinical study.