蜗神经发育不良患者的听力学特征分析

Auditory Characteristics in Patients with Cochlear Nerve Deficiency

目的探讨蜗神经发育不良(cochlear nerve deficiency,CND)患者的听力学特征。方法以30例(54耳)(男14例,女16例,年龄6月~29岁,平均4.9岁)内听道斜矢状位磁共振成像示蜗神经发育不良的患者为研究对象,回顾性分析患者的纯音测听或行为测听、声导抗、耳声发射、听性脑干反应(ABR)、听性稳态反应等听力学检测结果及颞骨高分辨CT(HRCT)结果,分析蜗神经发育异常者的听力学特征。结果 30例54耳蜗神经发育不良患者中,双侧24例(80%),单侧6例(20%),其中蜗神经缺如33耳,蜗神经细小21耳。54耳中,共有25耳(46.29%)伴内耳畸形,而单侧蜗神经发育不良者的对侧6耳中,50%(3耳)伴内耳畸形。纯音测听或行为测听和听性稳态反应结果均提示蜗神经发育不良患耳呈重度-极重度听力损失,且蜗神经缺如耳较蜗神经细小耳的听力损失程度更重。11耳(20.37%,11/54)蜗神经发育不良耳可在80~100 dB nHL高强度声刺激下引出听性脑干反应;6例双侧蜗神经发育不良者(20.0%,6/30)中7耳(1例双耳,5例单耳)全部频率或部分频率引出DPOAE,但其中5耳未引出ABR,2耳分别于100和90 dB nHL刺激声强下引出ABR。结论蜗神经发育不良患者常表现为重度-极重度听力损失,近一半伴内耳畸形,部分患耳可引出DPOAE,而ABR严重异常或缺失。

Objective To investigate the auditory characteristics of patients with cochlear nerve deficiency. Methods We enrolled 30 patients(54 ears) with cochlear nerve deficiency with 14 boys and 16 girls. They ranged from 6 months to 29 years old with a mean of 4.9 years old. They had undergone cochlear nerve HRMRI in this study. Audiological tests, including pure tone audiometry and behavioral audiometry,acoustic impedance, DPOAE, ABR, ASSR and HRCT, were retrospectively analyzed. This study also analyzed the auditory characteristics of patients with cochlear nerve deficiency. Results Of the 30 patients(54 ears) with cochlear nerve deficiency, 24 patients(80%) were affected bilaterally and 6 patients(20%) were unilateral, 33 ears were aplasia and 21 ears hypoplasia. The patients with cochlear nerve deficiency showed severe-to-profound hearing loss using pure tone audiometry and behavioral audiometry and ASSR. Those with aplasia tended to have worse hearing loss than those with hypoplasia, 20.1% ears with cochlear nerve deficiency showed the ABR responses at higher levels of acoustic stimulation. Out of the 30 patients,6(20%) patients had an audiometric profile of auditory neuropathy. In 46.3% ears, inner ear malformations were detected in the ear with cochlear nerve deficiency. Conclusion The patients with CND usually had severe-to-profound hearing losses and half of affected patients had inner ear malformations in the involved ear. Some of them had an audiometric profile of auditory neuropathy.