局部注射A型肉毒毒素在远隔部位的单纤维肌电图测定

目的研究局部注射美国产与国产Ａ型肉毒毒素（Ｂｏｔｏｘ与ＣＢＴＸ－Ａ）对远隔部位神经肌肉接头的影响。方法在７００余例自愿接受Ｂｏｔｏｘ或ＣＢＴＸ－Ａ注射治疗的患者中,选择条件匹配、积极配合且随访便利的４０例患者,分别在局部注射Ａ型内毒毒素（ＢＴＸ－Ａ）前及注射后２～３周、５～８周和４～５月（第２次注射前）,在伸指总肌或胜前肌进行单纤维肌电图（ＳＦＥＭＧ）检测,共检测１１９次。结果上下肢肌肉的ｊｉｔｔｅｒ　增加均在注射后２～３周最为明显,５～８周有所改善,４～５月时趋于正常;注射后２～３周的平均连续波间差（ＭＣＤ）改变与剂量呈正相关;纤维密度（ＦＤ）的变化则较为延迟或同时出现,４～５月时尚未恢复。Ｂｏｔｏｘ组与ＣＢＴＸ－Ａ组的ＳＦＥＭＧ变化差异无显著性意义。结论局部注射治疗剂量的ＢＴＸ－Ａ对远隔部位神经肌肉接头的功能确有临床下影响,毒素通过血液循环全身性分布的机制可能起主要作用;注射剂量直接影响远隔效应的轻重;注射后４～５月ｊｉｔｔｅｒ才趋于恢复,可作为重复治疗间期的参考,以避免出现严重并发症。

Remote effects of local injection of botulinum toxin type A

To assess the seventy and temporal profile of remote effects of botulinum toxintype A, BTX-A (Botox from Allergan Inc, USA and CBTX-A made by Lanzhou BiologicalProducts Institute,China) injected locally on neuromuscular junction. Methods Patients had enrolled in a prospective study for their movement disorders, 18 cases with Botox and 22 cases withCBTX-A were studied. Single fiber electromyography (SFEMG) in the extensor digitorum communis muscle or tibialis anterior muscle was performed before and 2 ~ 3 weeks, 5 ~ 8 weeks, 4~5 months after injection of Botox or CBTX-A. Results It was measured totally 119 times. Significant increase of jitter was demonstrated 2-3 weeks after injections in both groups and MCDwas in direct prOPortion to dose of injections. Fiber density value increased at the same time orlater and lasted until 4~ 5 months after injections. Conclusions Subclinical effects on neuro-muscular transmission of remote uninjected muscles after injections of Botox and CBTX-A aredemonstrated, which indicates that the toxin spread distantly from the site of injection. SFEMGis valuable for studying the pathogenesis of the remote effects of BTX-A and for avoiding reinjection too frequently.