肌萎缩侧索硬化症的重复电刺激研究

Repetitive nerve stimulation in amyotrophic lateral sclerosis

目的研究肌萎缩侧索硬化症(ALS)患者近端神经低频重复电刺激复合肌肉动作电位波幅递减的特点及其相关影响因素。方法应用常规低频重复电刺激(RNS)方法,分别刺激近端腋神经和副神经,前瞻性研究了87例ALS患者低频RNS复合肌肉三角肌和斜方肌动作电位波幅递减特点,以及和相关影响因素的关系,同时将其中RNS波幅递减阳性患者与同期39例重症肌无力患者的低频RNS波幅递减情况进行比较。结果 1ALS组三角肌和斜方肌RNS波幅递减阳性率分别为43.7%和49.4%,斜方肌阳性率高于三角肌。2ALS组三角肌和斜方肌RNS波幅递减与性别、起病年龄、病程、ALSFRS-r评分和疾病进展率无关。3ALS组三角肌和斜方肌RNS波幅递减与症状波动之间明显相关,症状波动者RNS波幅递减明显。4重症肌无力组三角肌和斜方肌RNS波幅递减幅度明显高于ALS组。结论 ALS患者近端肌肉RNS波幅递减现象并不少见,不能作为排除ALS的标准。斜方肌RNS波幅递减阳性率高于三角肌。重症肌无力患者RNS波幅递减幅度明显高于ALS患者,临床上对ALS患者伴无力症状波动且RNS波幅递减阳性者,应慎重诊断。

Objective To evaluate the features and related factors of decremental response in amyotrophic lateral sclerosis （ALS） patients to low-frequency repetitive nerve stimulation （RNS） in proximal nerves. Methods We performed RNS studies in proximal axillary and accessory nerves with recording in deltoid and trapezius mus- cle respectively in 87 ALS patients. Decremental compound muscle action potential （CMAP） and related factors were analyzed prospectively, and abnormal group of decremental response in ALS patients was compared with 39 pa- tients with myasthenia gravis. Results ① Abnormal decremental responses were found in 43.7% and 49.4% of ALS patients with deltoid and trapezius muscle recording respectively. They were found more frequent in trapezius muscle than those of deltoid muscle. ② There was no relationship of decremental response with gender, age, onset or course of disease, ALSFRS-r scores, or rate of disease progression in ALS patients. ③ There was significant rela- tionship between decremental response and fluctuating muscle weakness. Decremental responses decreased more ob- viously in ALS patients with fluctuating muscle weakness than in those with nonfluctuating muscle weakness. ④Dec- remental responses were greater in patients with myasthenia gravis than that in ALS patients. Conclusion Decre- mental response with proximal muscle recording is not an uncommon feature in ALS patients;therefore, it should not be treated as a criterium to rule out ALS. Abnormal decremental response of trapezius muscle is found more fre- quent than that of deltoid muscle. Decremental response range in patients with myasthenia gravis is significantly lar- ger than that in ALS patients. One should be more careful when diagnosing ALS patients with fluctuating muscle weakness and abnormal decremental response.