进行性腓骨肌萎缩症1A型电生理研究

Electrophysiological study in Charcot-Marie-Tooth disease type 1A

目的 研究 17p11.2 12基因重复的进行性腓骨肌萎缩 (CMT1A )症 1A型患者电生理特点。方法 应用肌电图仪检测和分析来自 2 1个家系的 2 2例CMT1A患者的电生理特征 ,包括肌电图及运动、感觉神经传导速度。结果 77.3 % ( 17/2 2 )的患者肌电图上出现纤颤、正相电位 ,81.8% ( 18/2 2 )的患者运动单位电位时限延长。CMT1A患者正中运动神经传导速度 (MCV)与无重复的CMT1患者相比差异无显著性意义 (t =1.6 3 ,P >0 .0 5 )。 90 .9% ( 2 0 /2 2 )的患者下肢感觉神经传导速度 (SCV)引不出 ,分别有 13例和 12例患者正中神经和尺神经的SCV引不出。 1例患者所检神经的SCV均在正常范围 ,而他的MCV都明显低于正常 ;1例患者尺神经SCV正常 ,而其MCV <2 0m /s ;还有 1例患者正中神经SCV正常 ,而其MCV只有 38m /s。但 13例正中SCV未引出的患者中 ,对应的MCV仅 1例未测出 ,最快的传导速度高达41.6m/s ;12例尺神经SCV未引出者 ,对应的MCV仅 3例未测出 ,最快的传导速度为 32m /s。结论 该组CMT1A患者电生理特点为大多数患者肌电图呈神经源性损害 ;下肢感觉神经病变重于上肢 ;感觉神经与运动神经不一定同时受累 ,受累的严重程度亦可能不一致 ,存在个体差异。

Objective To study the electrophysiological features in Charcot Marie Tooth (CMT) disease type 1A with duplication on chromosome 17p11.2 12.Methods Electromyography(EMG) as well as motor conduction velocities(MCV) and sensory conduction velocities(SCV) were detected and analyzed in 22 patients coming from 21 unrelated families by electromyography.Results 81.8% of them had prolonged motor unit potential limit.Median MCV showed that there was no significant difference between CMT1A patients and that of CMT1 patients without duplication(t= 1.63 ,P> 0.05 ).Values of SCV for the lower limbs were not obtained in 12 and 13 patients respectively.All values of SCV were in normal range in one patient,but his values of MCV were significantly lower than that of normal ones.In one patient,the value of lunar SCV was normal and his corresponding MCV<20 m/s.In another patient,the value of median SCV was normal and his MCV of median nerve was only 38 m/s. But among 13 patients whose median SCV was undetectable,only one patients′ median MCV was undetectable.The fastest velocity of them was 41.6 m/s.And among 12 patients whose lunar SCV was undetectable,only 3 patients′ lunar MCV was undetectable.The fastest velocity of them was 32 m/s.Conclusion The electrophysiological features of CMT1A patients in this group were that most of them were neurogenic damages.The damages of sensory nerves in the lower limbs were more severe than that in the upper limbs.Sensory nerves and motor nerves were probably not damaged at the same time and the severity may be different in different patients.