肌萎缩侧索硬化患者205例的神经传导特点分析

Nerve conduction studies in 205 patients with amyotrophic lateral sclerosis

目的 分析肌萎缩侧索硬化（ALS）患者的神经传导和F波特点,并探讨其与肌力、病程和首发部位等之间的关系.方法 收集于1997年1月至2008年5月期间我院门诊或病房收治的ALS患者205例,均采用常规肌电图检查,测定其运动神经传导、F波以及感觉神经传导（SCV）.结果 在205例ALS患者中,仅有3例SCV异常,正中神经、尺神经及胫后神经末端潜伏期（DML）延长者分别占24.9%（48/193）、15.3%（25/163）、21.2%（7/33）,复合肌肉动作电位（CMAP）波幅下降者分别占57.0%（110/193）、49.7%（81/163）、39.4%（13/33）;68.9%（122/177）患者F波出现率下降,其中31.1%（55/177）F波出现率为0,肌力下降者DML、CMAP波幅及F波出现率改变明显.肢体起病组正中神经CMAP波幅下降[81.5%（53/65）]和F波异常率[70.9%（44/62）出现率下降,45.1%（28/62）出现率为0]较延髓部起病者[32.4%（11/34）;F波38.2%（13/34）出现率下降,14.7%（5/34）出现率为0]更明显,两组比较差异有统计学意义（x2=23.629、9.753、9.029,均P〈0.01）;DML异常两组间差异无统计学意义.Logistic回归分析显示CMAP波幅的降低与上肢远端肌力、首发部位、病程显著相关,F波出现率的降低与上肢远端肌力、首发部位相关.结论 ALS患者可出现DML延长和CMAP波幅降低（后者改变更显著）,F波出现率明显下降而传导速度相对正常;DML、CMAP波幅及F波出现率的异常与肌力明显相关.首发部位为肢体和（或）上肢远端肌力下降者CMAP波幅及F波异常率更明显.

Objective To investigate the F-wave and nerve conduction in patients with amyotrophic lateral sclerosis （ALS） and explore the correlation between these parameters and muscle strength, disease duration and onset site.Methods The data of outpatients and inpatients diagnosed with ALS were collected in Peking Union Medical College Hospital from January 1997 to May 2008.Standard sensory and motor nerve conduction study of the median nerve, ulnar nerve and tibial nerve was performed in 205 patients with ALS.F-wave velocity and frequency was measured in median nerve.Parameters for analyses included sensory conduction velocity and amplitude, distal motor latency （DML）, and compound muscle action potential （CMAP） amplitude.Correlation between muscle strength and DML, CMAP amplitude or F-wave frequency were also explored.Results Delayed DML of the median nerve, ulnar nerve and tibial nerve were found in 24.9% （48/193）, 15.3% （25/163）, 21.2% （7/33） of patients respectively.Decreased CMAP amplitudes were found in 57.0% （110/193）, 49.7% （81/163）, 39.4% （13/33） of patients respectively.Decreased F-wave frequency of the median nerve was found in 68.9% （122/177） of patients.The abnormality of DML,CMAP amplitude and F-wave frequency of median nerve were increased in weaker muscles.Decreased median nerve CMAP amplitude （81.5% （53/65）） and F-wave abnormality （decreased persistence 70.9%（44/62）, absent responses 45.1% （28/62）） in spinal onset groups were significantly higher than those in bulbar onset groups （CMAP 32.4% （11/34）; F-wave： decreased persistence 38.2% （13/34）, absent responses 14.7% （5/34）; x2 = 23.629, 9.753, 9.029,all P 〈0.01）.Compared with the bulbar onset group,the abnormality of DML in spinal onset group was higher, but not reach statistical significance.Logistic regression revealed a strong direct association between decreased CMAP amplitudes and upperextremity muscles strength, disease duration and onset symptom.Abnormality of F-wave frequency was associated with upper-extremity muscles strength and onset symptom.Conclusions Delayed DML and decreased amplitude of CMAP are found in ALS patients.CMAP amplitude is a sensitive parameter related to the severity of ALS.F-wave velocity is relatively normal while F-wave frequency of the median nerve is correlated with muscle strength.Decreasing CMAP amplitude and F-wave frequency are correlated strongly with muscle weakening,disease duration and symptom onset over limbs.