Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Department of Neurology, Christian Doppler Klinik, Paracelsus Medical University, Salzburg, Austria; Karl Landsteiner Institut für Neurorehabilitation und Raumfahrtneurologie, Salzburg, Austria.
Department of Neurorehabilitation, Hospital of Vipiteno, Vipiteno, Italy; Research Unit for Neurorehabilitation South Tyrol, Bolzano, Italy.
Brain Res Bull. 2018 Jun;140:258-269. doi: 10.1016/j.brainresbull.2018.05.016. Epub 2018 May 24.
Transcranial magnetic stimulation (TMS) may represent a valuable tool for investigating important neurophysiological and pathophysiological aspects of myoclonus. Moreover, repetitive TMS (rTMS) can influence neural activity. In this review we performed a systematic search of all studies using TMS in order to explore cortical excitability/plasticity and rTMS for the treatment of myoclonus due to different aetiologies. We identified and reviewed 40 articles matching the inclusion criteria; 415 patients were included in these studies. The reviewed TMS studies have detected abnormalities in motor cortex excitability and sensorimotor plasticity. The most consistent finding is a decrease in intracortical inhibition. Short-interval intracortical inhibition (SICI) is reduced in myoclonic epilepsies. Unlike the juvenile and the benign myoclonus epilepsy, long-interval intracortical inhibition, interhemispheric inhibition and sensorimotor integration were altered in patients with progressive myoclonic epilepsies. In patients with myoclonus-dystonia the results are partly conflicting. Cortical membrane excitability was impaired while parameters assessing cortical synaptic activity were normal in DYT11 gene carriers. In other studies normal SICI suggests that the GABAergic cortical circuits are largely intact and that the mechanisms of myoclonus-dystonia are different from those for cortical myoclonus and other dystonic disorders. In conclusion, different TMS study protocols have provided new insights into sensorimotor plasticity and cortical excitability of the different forms of myoclonus, and have shed some light on the pathophysiology of this movement disorder. Well-defined motor cortical excitability patterns can be identified in the different disorders characterized by myoclonus, even if preliminary findings should be confirmed in future studies in larger cohorts of patients. Repetitive TMS might have therapeutic potential at least in some patients with myoclonus, similar to that reported in other neurological and psychiatric disorders.
经颅磁刺激（TMS）可能是研究肌阵挛重要神经生理和病理生理方面的一种有价值的工具。此外，重复经颅磁刺激（rTMS）可以影响神经活动。在本综述中，我们进行了一项系统的搜索，以探讨不同病因导致的肌阵挛的皮质兴奋性/可塑性和 rTMS 的治疗作用。我们共确定并回顾了 40 篇符合纳入标准的文章，这些研究共纳入 415 例患者。综述的 TMS 研究检测到运动皮质兴奋性和感觉运动可塑性异常。最一致的发现是皮质内抑制减少。短间隔皮质内抑制（SICI）在肌阵挛性癫痫中降低。与青少年和良性肌阵挛性癫痫不同，进展性肌阵挛性癫痫患者的长间隔皮质内抑制、半球间抑制和感觉运动整合发生改变。肌阵挛-肌张力障碍患者的结果则部分存在冲突。皮质膜兴奋性受损，而评估皮质突触活动的参数正常。在 DYT11 基因携带者中，皮质兴奋性受损，而评估皮质突触活动的参数正常。在其他研究中，正常的 SICI 表明 GABA 能皮质回路基本完整，肌阵挛-肌张力障碍的机制与皮质肌阵挛和其他肌张力障碍疾病不同。总之，不同的 TMS 研究方案为不同形式的肌阵挛的感觉运动可塑性和皮质兴奋性提供了新的见解，并为这种运动障碍的病理生理学提供了一些线索。即使在未来更大样本量的患者研究中，也应确认初步结果，不同以肌阵挛为特征的疾病中可以识别出明确的运动皮质兴奋性模式。rTMS 至少在一些肌阵挛患者中具有治疗潜力，这与其他神经和精神疾病中的报道相似。
