复合肌肉动作电位记录及在部分性运动传导阻滞诊断中的应用  

Compound muscle action potentials recordings and diagnostic criteria of partial conduction block

作　　者：汪仁斌[1] 刘兴洲[2] 毛坤[1] 孙少杰[1] 焦劲松[1] 王国相[1] 

机构地区：[1]中日友好医院神经内科,北京100029 [2]北京三博脑科医院神经科,北京100045

出　　处：《中日友好医院学报》2005年第3期140-142,共3页Journal of China-Japan Friendship Hospital

摘　　要：目的:测试正常国人不同神经节段的复合肌肉动作电位(CMAP)相对波幅的正常变异,结合多灶性运动神经病的CMAP衰减特征,探讨运动神经传导阻滞的诊断标准。方法:用表面电极常规方法记录正中神经、尺神经多节段复合肌肉动作电位,正常组共169条,多灶性运动神经病26条,分析波幅、面积和时限等参数。结果:正常人不同神经节段间CMAP衰减(%)具有较大变异:尺神经肘下-腕4.7±4.7%,肘上-肘下3.6±3.5%,肘上-腕8.2±6.3%,腋-腕13.3±7.9%;正中神经肘下-腕4.4±3.0%,肘上-肘下1.8±4.3%,肘上-腕6.1±5.6%,腋-腕8.8±7.1%。病变组不同神经节段的波幅衰减更明显,与正常组相比差异显著(P<0.01)。结论:在部分性运动神经传导阻滞的诊断中,不同的神经节段应采用不同的诊断标准,大于实测波幅衰减的x+2.58SD可诊断为可能部分性运动传导阻滞;考虑到时间离散的影响因素,建议将CMAP波幅衰减大于相应神经节段95%正常上限值诊断为肯定的部分性运动神经传导阻滞。Objective:To study characteristics of amplitude decay over different nerve segments between normal subjects and multifocal motor neuropathy(MMN),and establish diagnostic criteria for the partial conduction block.Methods:CMAPs were recorded with supramaximal stimulation through surface electrodes in 169 nerves at different nerve segments of normal subjects and the results were compared with that of 26 nerves of MMN.The regular motor and sensory conduction velocity were simultaneously evaluated.Results:Amplitude decay of the CMAP varied considerably at different nerve segments in normal subjects,the extent of the variation were 4.7%±4.7%,3.6%±3.5%,8.2%±6.3%,13.3%±7.9% for the ulnar nerve at the segment of below elbow to wrist,across elbow,above elbow to wrist and axilla to wrist,respectively;4.4%±3.0%,1.8%±4.3%,6.1%±5.6%,8.8%±7.1% for the median nerve at the segment of below elbow to wrist,across elbow,above elbow to wrist and axilla to wrist,respectively.The amplitude decay in neuropathic groups had significant differences as compared with that of normal subjects (P<0.01).Conclusion:Electrodiagnostic criteria for partial conduction block should be considered individually for different nerve and nerve segments.The normal mean plus 2.58SD of CMAP amplitude decay over a specific segment can be suggested as a probable partial conduction block in diagnosis.For differentiating conduction block from temporal dispersion,the 95% normal upper limits of CMAP decay over different nerve segments is recommended for a definite partial conduction block.

关 键 词：复合肌肉动作电位 传导阻滞 波幅衰减 多灶性运动神经病 

分 类 号：R745[医药卫生—神经病学与精神病学]