平山病的临床与神经电生理学特点分析

目的：分析平山病的临床与神经电生理学特点，以提高对平山病的诊断水平。方法：对21例确诊为平山病的患者进行运动和感觉传导速度、肌电图（EMG）、F波及交感皮肤反应（SSR）等神经电生理学检查。结果：对126条神经进行检测，神经传导速度（NCV）测定总异常率为16．7％（21／126），主要表现为远端运动潜伏期（DML）延长及复合肌肉动作电位（CMAP）波幅下降，感觉神经传导速度均正常。F波平均最小潜伏期为（28．70±3．10）ms，平均出现率为47．70％，总异常率为76．2％。患者患侧上肢及对侧上肢远端肌（不包括肱桡肌）EMG呈神经原性改变者分别为1000及90．5％，主要异常表现为出现自发电位运动单位电位（MUP）时限延长、波幅增宽、多相波增多及募集相等异常。上肢远端肌EMG异常率为91．5％，明显高于上肢近端肌的8．0％及下肢肌的3．5％。结论：平山病可出现神经电生理上的亚临床改变，神经电生理检查对其有较高的诊断价值。

Clinical and Electroneurophysiological characteristics of Hirayama disease

Objective： To promote the understanding and diagnostic acuity of Hirayama disease （HD） by analizing the clinical electroneurophysiological characteristics of HD. Methods： Electroneuro physiological studies were performed in 21 patients with HP on the clinical ground including motor con duction velocity（MCV）, sensory conduction velocity（ SCV）, electromyography（ EMG）, F-wave and sympatlxetic skin response（SSR）. Results： The abnormality rate of the NCV in 126 examined nerves was 16.7% （21/126）, predominantly in the motor nerves, characterized by the delay of distal motor latency （DML） and the lower of the compound muscle action potential （CMAP）amplitude. The sensory conduction velocity（SCV）study showed no abnormality. The mean minimal latency of F-wave in median nerves was 28.70! 3. 10 ms with the mean persistence rate of 47. 7%. The total abnormality of NCV was 76.2%. The neurogenic abnormalities on EMG were deected in extremity muscles, with exception of brachioradial muscle of upper limbs. In all the 33 patients damage was found on the illness-side and 90.5% on the contralateral side, including spontaneous potentials, motor unit potentials（MUPs） changes（ the increase of latency, the augment of the amplitude, the increase of the polyphasic waves, and the pattern of the recruitment）. EMG abnormality rate of distal muscles 91.5% was significantly higher than that of the proximal muscles of upper limbs 8.0% and also muscles of lower limbs 3.5%. Conclusion.. Electroneurophysiological changes may be detected in some patients with subclinical Hirayama disease,of which the electrophysiological test is valuable in establishing early diagnosis.