Odergren T, Tollbäck A, Borg J
Department of Neurology, Karolinska Hospital, Stockholm, Sweden.
Electroencephalogr Clin Neurophysiol. 1994 Oct;93(5):325-9. doi: 10.1016/0168-5597(94)90119-8.
Electromyographic (EMG) single motor unit potentials (MUPs) of the sternomastoid muscles (STM) were made before and after repeated treatment with botulinum type A toxin (Bx) for cervical dystonia. Post-treatment examinations were 6-25 weeks after the latest injection, when symptoms and EMG interference pattern had recurred and signs of denervation were scarce. Concentric needle EMG records of 200 motor unit potentials in 10 patients showed reduced durations and areas after treatment (P < 0.05). Increased polyphasia or satellite potentials were not observed. Macro-EMG records of 110 MUPs in 6 patients showed reduced amplitudes and areas in the injected STM when compared to the untreated side (P < 0.05). Fibre density was within the same range (1.0-1.2). The results indicate that the pattern of the terminal innervation is mainly restored even after repeated Bx treatments, but the number or size of active muscle fibres within the motor unit is reduced. The clinical relapse could be due to recovery of the original nerve terminals, or to nerve sprouts closely imitating the blocked terminal nerve twigs or both.
对颈肌张力障碍患者，在反复注射A型肉毒毒素（Bx）治疗前后，分别记录其胸锁乳突肌（STM）的肌电图（EMG）单运动单位电位（MUPs）。治疗后检查在最近一次注射后6 - 25周进行，此时症状和EMG干扰图形已复发，且失神经支配迹象较少。对10例患者的200个运动单位电位进行同心针EMG记录，结果显示治疗后电位持续时间和面积减小（P < 0.05）。未观察到多相波或卫星电位增加。对6例患者的110个MUPs进行宏肌电图记录，结果显示与未治疗侧相比，注射侧STM的电位幅度和面积减小（P < 0.05）。肌纤维密度在相同范围内（1.0 - 1.2）。结果表明，即使反复进行Bx治疗，终末神经支配模式仍主要得以恢复，但运动单位内活性肌纤维的数量或大小减少。临床复发可能是由于原始神经末梢的恢复，或由于神经芽紧密模仿被阻断的终末神经分支，或两者兼而有之。
