91例肌萎缩侧索硬化症的F波和神经传导研究

目的探讨肌萎缩侧索硬化症(ALS)F波和神经传导改变的特点.方法所有患者均采用常规方法测定感觉神经传导速度(SCV)、运动末端潜伏期(distal motor latency,DML)和F波,后者的测定包括潜伏期和/或传导速度及出现率.分析了DML和复合肌肉动作电位(compound muscle action potential,CMAP)波幅、F波出现率与肌力的关系.结果在91例ALS患者中,仅有3例SCV异常;正中神经、尺神经及胫后神经DML延长者分别占16.7%、13.8%、7.1%,CMAP波幅下降者分别占50.0%、44.6%、28.6%;5.0%患者F波传导速度异常,48例患者F波出现率下降,其中19例出现率为0.肌力下降者DML、CMAP波幅及F波出现率改变明显.结论ALS患者可出现DML延长和CMAP波幅降低,二者比较后者的改变更显著;F波传导速度相对正常而出现率下降明显;DML、CMAP波幅及F波出现率的异常与肌力明显相关(P均＜0.01).

F-wave and Nerve Conduction Studies in 91 Patients with Amyotrophic Lateral Sclerosis

Objective To investigate the features of F-wave and nerve conduction in patients with amy-otrophic lateral sclerosis (ALS). Methods Standard sensory and motor nerve conduction were performed in median nerve.ulnar nerve and tibial nerve in 91 patients with ALS. F-wave was studied in median nerve. Parameters studies included sensory conduction velocity and amplitude, distal motor latency (DML) and compound muscle action potential (CMAP) amplitude, F-wave velocity and frequency. The relations of muscle strength with DML, CMAP amplitude and F-wave frequency were also analyzed in median nerve. Results Delayed DML of median nerve, ulnar nerve and tibial nerve were found in 16. 6%, 13. 9% ,7. 2% patients respectively, and the decreased CMAP amplitudes were found in 50. 0%,44. 7%,28. 6% patients respectively; Decreased F-wave velocity was found in 6.6% patients, decreased F-wave frequency was found in 60% patients. Only 3 cases had abnormal sensory conduction. The abnormality of DML, CMAP amplitude and frequency of median nerve were more severe in weaker muscles. Conclusions Delayed DML and decreased amplitude of CMAP are found in ALS patients. The amplitude of CMAP is a sensitive parameter related to the severe of ALS. F-wave velocity is relatively normal while F-wave frequency significantly decreases in ALS. The abnormal of DML, CMAP amplitude and F-wave frequency are correlated with muscle strength.