人工耳蜗植入前电诱发听觉脑干反应测试及其意义

Detection of the electric brain stem auditory response before cochlear implantation and its significance

目的 分析人工耳蜗植入患者电极植入前电诱发听觉脑干反应（electric auditory brainstem response,EABR）的测试结果并初步探讨其意义.方法 选择2008年2月至2014年12月在北京协和医院接受澳大利亚Cochlear Nucleus 24R多通道人工耳蜗植入手术的187例耳蜗结构正常患者,其中男105例、女82例;植入侧无残余听力152例,有残余听力35例.患者全身麻醉下行常规人工耳蜗植入手术,在电极植入前采用自主研制的电刺激器、美国Bio-logic听觉诱发电位仅及Cochlear人工耳蜗调试软件进行EABR测试.测量并分析EABR波形,各波潜伏期和波间期,V波波幅、阈值及V波输入/输出（I/O）曲线斜率.采用SPSS19.0统计软件进行统计学分析.结果 EABR的Ⅱ、Ⅲ、Ⅳ、Ⅴ波与声诱发ABR相似,不同年龄波形分化不一,男女无明显性别差异.187例耳蜗结构正常患者均记录到EABR的Ⅴ波,引出率达100％;50 μs脉宽电脉冲刺激下,Ⅴ波平均阈值（156.37±21.44）电流级（CL）,平均动态范围（36.33 ±8.63）CL.阈上20 CL电刺激时,Ⅱ波、Ⅲ波、V波的平均潜伏期分别为（1.54±0.12）ms、（2.06±0.23） ms、（4.14±0.25） ms,Ⅲ-Ⅴ间期为（2.08±0.24） ms,Ⅴ波平均波幅为（0.35±0.07）μⅤ.术后1个月开机,187例患者均有不同程度的听性反应,开机平均最大舒适阈值（C值）为（163.55±27.43） CL,与EABR阈值有显著相关性（r=0.915,P=0.013）.无残余听力组（35例,年龄和性别与有残余听力组相匹配）EABR阈值为（163.82±16.21）CL、Ⅴ波I/O曲线斜率为0.035 227±0.013 918,有残余听力组阈值为（148.41±15.38） CL、I/O曲线斜率为0.041 364±0.013 623,两组配对t检验,差异均具有统计学差异（t值分别为15.838和4.328,P值均〈0.05）.结论 本研究EABR检测方法结果可靠,引出率高.电极植入前通过EABR检测可以评估患者电听觉能力,为筛选人工耳蜗植入适应证提供帮助.

Objective Analysis of the outcome of the electric brain stem auditory response （EABR） before cochlear implantation （CI） and the mapping parameters after CI in 187 cases,to explore the significance of EABR before CI.Methods From February,2008 to December,2014,EABR were performed in 187 patients with normal cochlear structures before CI with Nucleus 24R multi-channel cochlear.Including 105 cases of male,82 cases of female;152 cases of no residual hearing,35 cases of residual hearing.Self-design electrical stimulator and US Bio-logic auditory evoked potential were taken,EABR were performed under general anesthesia before CI,recording EABR waveforms,measuring the latency of Ⅱ,Ⅲ,Ⅳ,Ⅴ wave and the Ⅲ-Ⅴ interval,Ⅴ-wave amplitude,Ⅴ-wave threshold and I/O curve slope.Data were analysis by SPSS19.0.Results EABR waveforms were recorded in all 187 patients.The Ⅱ,Ⅲ,Ⅳ,Ⅴ waves are similar with the acoustic evoked ABR,the waveforms differentiation were different in ages,but no significant difference in gender.At 50 μs pulse electrical stimulation,the average threshold of V-wave was （156.37 ± 21.44） CL,the average dynamic range was （36.33-± 8.63） CL.20 CL above the threshold,average latency of wave Ⅱ,Ⅲ,Ⅴ was （1.54 ± 0.12） ms,（2.06 ± 0.23） ms and （4.14 ± 0.25） ms,the Ⅲ-Ⅴ interval was （2.08 ± 0.24） ms,the average amplitude of Ⅴ-wave was （0.35-0.07） μⅤ.One month later,the 187 patients achieved different degrees of hearing,the average C value of mapping was （163.55 ± 27.43）CL,significantly correlated with EABR threshold（r =0.915,P =0.013）.The EABR threshold in 35 cases of no residual hearing value was （163.82 ± 16.21）CL and V-wave I/O curve slope was 0.035 227 ± 0.013 918,and the threshold was （148.41 ± 15.38）CL,the slope was 0.041 364 ±0.013 623 in paired group of 35 residual hearing patients,there was a statistically significant difference between two groups（t =15.838 and 4.328,P 〈 0.05）.Conclusions The EABR detection method is reliable,extraction rate is high.EABR can be used to evaluate the auditory pathway before inserting electrode,which could provide the help for the screening operative indications of CI.