听觉神经病

Auditory neuropathy

目的 探讨听觉神经病的临床特点、听力学及电生理特征。方法 总结了 17例听觉神经病患者的病史、纯音及语言听力、镫骨肌反射、听性脑干反应 (auditorybrainstemresponse ,ABR)、耳蜗电图、鼓岬电刺激试验、耳声发射及对侧声抑制试验的特点。结果 该病多在青春期后起病 ,女性较多发 ,表现为渐进性双耳对称性听力下降 ,纯音听力以低频损失为主 ,语言接受阈升高 ,分辨率下降 ,镫骨肌反射及ABR引不出或阈值明显升高与纯音听力不成比例 ,耳蜗微音器电位正常 ,听神经动作电位引不出 ,耳声发射波幅高、时程长且不为对侧声刺激所抑制。结论 听觉神经病的诊断应在除外各种已知原因的感音神经性聋后 ,根据其纯音听力与客观测听的不一致及电生理学上的耳蜗活动与中枢系统反应分离的特征作出 ,对该病的认识尚需进一步深入。

Objective To study the clinical feature and audiological and electrophysiological characteristics of auditory neuropathy Methods The history, audiometry, stapedial reflex, electrocochleogram, auditory brainstem response, promontory stimulation tests, otoacoustic emissions(OAE) and its contralateral supression tests were studied in 17 cases of auditory neuropathy Results The patients were predominently female teenagers with a history of gradual onset of bilateral hearing loss, pure tone audiometry revealed symmetric ascending audiograms with moderate hearing loss at frequencies below 1 kHz, but relatively normal hearing at 2 kHz and above. Speech reception thresholds were between 40 to 85 dB HL, discrimination score was from 29% to 68% Stapedial reflex, auditory brainstem response and compound action potentials were absent or threshold elevated disproportionately to the pure tone threshold. All of the patients had normal cochlear microphonics and robust spontaneously and transiently evoked otoacoustic emissions (SOAE and TEOAE), the TEOAE showed no contralateral suppression effects as seen in normal subjects Conclusion The diagnosis of the disease depends on the discrepancies between subjective and objective hearing and pre neural and neural responses The crossed olivocochlear bundle function testing in terms of contralateral acoustic stimulation induced otoacoustic emission reduction is specific for differential diagnosis There is a need for more awareness of the disease among otolaryngologists and neurologists