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：近30年来，非侵入性刺激（noninvasive stimulation）已被广泛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：本批判性综述阐明了此类技术应用于运动障碍的理论依据，并基于迄今为止已开展的主要临床试验总结了最佳临床证据。方法：由全国代表性专家团队对相关文献进行全面梳理，以分析驱动运动障碍领域经颅磁刺激（transcranial magnetic stimulation, TMS）与经颅直流电刺激（transcranial direct current stimulation, tDCS）临床决策的关键因素。针对每种疾病阐述了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，TMS或可有效改善帕金森病（Parkinson’s disease, PD）患者的运动症状与抑郁症状。其在其他运动障碍中的治疗效果尚不明确。TMS可能对局灶性手部肌张力障碍、原发性震颤及小脑性共济失调具有治疗效果。此外，TMS在减轻抽动秽语综合征（Tourette syndrome）的抽动症状方面大概率无效。最后，tDCS或可有效改善帕金森病患者的步态。结论：尽管优化常规临床实践中提升阳性结局的刺激范式仍有待明确，但现有证据支持将非侵入性刺激应用于特定运动障碍的部分症状。同样，最佳刺激范式与应答者特征仍需在采用标准化治疗与评估范式的大型临床试验中开展研究，此类试验亦可明确是否可实现真正的长期获益。