Use of non-invasive stimulation in movement disorders: a critical review

Abstract Background: Noninvasive stimulation has been widely used in the past 30 years to study and treat a large number of neurological diseases, including movement disorders. Objective: In this critical review, we illustrate the rationale for use of these techniques in movement disorders and summarize the best medical evidence based on the main clinical trials performed to date. Methods: A nationally representative group of experts performed a comprehensive review of the literature in order to analyze the key clinical decision-making factors driving transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) in movement disorders. Classes of evidence and recommendations were described for each disease. Results: Despite unavoidable heterogeneities and low effect size, TMS is likely to be effective for treating motor symptoms and depression in Parkinson’s disease (PD). The efficacy in other movement disorders is unclear. TMS is possibly effective for focal hand dystonia, essential tremor and cerebellar ataxia. Additionally, it is likely to be ineffective in reducing tics in Tourette syndrome. Lastly, tDCS is likely to be effective in improving gait in PD. Conclusions: There is encouraging evidence for the use of noninvasive stimulation on a subset of symptoms in selected movement disorders, although the means to optimize protocols for improving positive outcomes in routine clinical practice remain undetermined. Similarly, the best stimulation paradigms and responder profile need to be investigated in large clinical trials with established therapeutic and assessment paradigms that could also allow genuine long-term benefits to be determined.

摘要：
背景：无创神经调控技术在过去30年间被广泛应用于研究与治疗包括运动障碍在内的多种神经系统疾病。
目的：本批判性综述旨在阐明此类技术应用于运动障碍疾病的理论依据，并基于迄今已开展的主要临床试验总结最优临床证据。
方法：由具有全国代表性的专家团队对相关文献进行全面系统梳理，以分析驱动经颅磁刺激（transcranial magnetic stimulation, TMS）与经颅直流电刺激（transcranial direct current stimulation, tDCS）在运动障碍疾病中应用的关键临床决策因素，并针对每种疾病明确证据等级与推荐意见。
结果：尽管存在不可避免的异质性与较小的效应量，经颅磁刺激（TMS）在改善帕金森病（Parkinson’s disease, PD）患者的运动症状与抑郁症状方面或具有有效性。其在其他运动障碍疾病中的疗效尚不明确。经颅磁刺激对局限性手部肌张力障碍、特发性震颤与小脑共济失调可能具有一定疗效。此外，经颅磁刺激在改善抽动秽语综合征的抽动症状方面大概率无效。最后，经颅直流电刺激（tDCS）或可有效改善帕金森病患者的步态障碍。
结论：尽管目前仍未明确可在常规临床实践中优化方案以提升正向疗效的具体手段，但现有证据表明无创神经调控技术在特定运动障碍疾病的部分症状中具有应用前景。同样，最佳刺激范式与应答者特征仍需通过采用标准化治疗与评估范式的大型临床试验开展进一步研究，此类试验亦需验证其长期治疗收益的真实性。