听力学检测在听神经病诊断中的意义

目的:分析听神经病(auditory neuropathy,AN)听力学及神经生理学特点,并探讨其诊断策略。方法:对37例患者在采集病史和耳科检查的基础上,行系统的听力学检查,包括纯音测听、言语识别率、声导抗、听性脑干反应(auditory brainstem response,ABR)、耳蜗微音电位(cochlear microphonics,CM)、中潜伏期反应(MLR)、诱发耳声发射(evoked otoacoustic emissions,EOAEs)以及影像学(CT和/或MRI)和周围神经系统检查。结果:纯音测听多为轻到中度上升型听力损失,37例患者鼓室图均呈“A”型、镫骨肌反射ABR均引不出或明显异常,但CM均正常。5例患儿未引出EOAEs,其中2例有新生儿缺血缺氧史,其余32例皆正常引出。10例患者影像学和周围神经系统未见异常。结论:对AN的诊断应依据听力学及神经生理学特点,推荐联合应用EOAEs、ABR和CM电生理检查,以免漏诊、误诊。

Significance of audiological measurements in diagnosis of auditory neuropathy

Objective: To analyze audiological and neurophysiological characteristics in patients with auditory neuropathy(AN)and to explore diagnostic stratity. Methods:Audiological measurements(pure tone,speech discrimination score,acoustic immittance,EOAEs,ABR,CM,MLR) and peripheral neurological tests were conducted and evaluated in 37 patients with AN. Ten patients received CT scan or MRI examination. Results:Pure tone audiometry mostly revealed symmetric ascending audiograms with mild to moderate hearing loss. All patients had type "A" tympanogram and normal CM. Except 5 infants, 32 patients elicited normal EOAEs. Peripheral neurological tests and CT or MRI showed normal findings. Conclusion: The diagnosis of AN in patients should focus on analyzing the audiological and neurophysiological characteristics. Combined use of EOAEs,ABR and CM is recommend.