tDCS同步偏瘫上肢FES对脑卒中后功能恢复的多模态肌电与神经成像技术研究

How to improve the function of hemiplegia upper extremity is an urgent problem to be solved at present. Functional magnetic resonance imaging(fMRI) related research has shown that functional electrical stimulation(FES) can activate the function of brain regions associated with functional recovery of hemiplegia upper extremity. Transcranial direct-current stimulation(tDCS) can enhance the cortex activation and regulate functional connectivity(FC) for different brain network. Based on the findings, we propose tDCS in combination with FES as a new method of rehabilitation to improve the recovery of the upper extremity. Patients with upper extremity dysfunction during stroke recovery were randomly divided into tDCS+FES group, tDCS+sham FES group, and sham tDCS+FES group. The patients were treated by 4-week combined therapy intervention. Scale and surface electromyography(sEMG) assessment were used to evaluate upper extremity function. Motor evoked potential (MEP) and diffusion tensor imaging(DTI) were used to detect the structural and functional plasticity changes in corticospinal tract. The resting state fMRI(rsfMRI) was used to analyzed FC in the brain network and Magnetic resonance spectroscopy(MRS) was performed to detect cortical neurotransmitter levels so as to clarify the dynamics of overall excitability of the brain network. Multimodal neuroimaging and electromyography illustrate the mechanism of combined therapy and provide an effective treatment model for the central and peripheral nervous system in stroke rehabilitation.

脑卒中后偏瘫上肢功能恢复是脑卒中康复的难题。我们前期研究发现，作用于肢体的功能性电刺激（FES）能改善患者偏瘫肢体功能，并能激活与偏瘫上肢功能恢复相关脑区；后续研究发现，经颅直流电刺激（tDCS）能调节上述脑区之间的功能连接（FC）。据此，我们假设tDCS联合肢体FES会进一步促进脑卒中偏瘫上肢功能恢复。本研究拟采用tDCS同步FES治疗脑卒中恢复期上肢偏瘫患者，将患者随机分为tDCS+FES组、tDCS+FES安慰刺激组、tDCS安慰刺激+FES组，联合治疗4周；治疗前后采用临床量表及表面肌电评估上肢功能，通过运动诱发电位、脑网络影像学检测明确大脑皮质结构及功能可塑性变化，阐明相关脑区激活、脑网络FC强度及皮层神经递质水平之间的内在联系和动态变化规律；基于多模态肌电与神经成像技术探讨tDCS同步FES改善脑卒中偏瘫上肢功能的神经机制，为脑卒中偏瘫上肢康复提供一种中枢+外周的高效治疗模式。

功能性电刺激（FES）能够改善肢体运动功能，主要通过外周刺激促进皮质可塑性变化；若联合一种直接兴奋大脑皮质的康复治疗技术，是否能够增强传统康复治疗技术的康复效果？经颅直流电刺激(tDCS）能够直接调节皮质功能状态，且几乎不引起不良反应；文献报道及我们前期的研究均显示：tDCS能够激活运动相关脑区，调节运动皮质与其他大脑皮质之间的功能连接。基于此，tDCS联合FES是否能够通过直接和间接两个途径调节皮质可塑性，影响康复的最终疗效，值得进一步研究。本研究拟采用tDCS同步FES治疗脑卒中上肢偏瘫患者。随机分为tDCS+FES组、tDCS+FES安慰刺激组、tDCS安慰刺激+FES组。临床量表及表面肌电评估明确上肢功能改善情况；磁刺激MEP等指标、静息态fMRI明确tDCS同步FES改善偏瘫上肢功能的多模态脑网络机制。.研究结果示：tDCS+FES组、tDCS+FES安慰刺激组、tDCS安慰刺激+FES组治疗后Fugl-Meyer评分(FMA) 和改良巴氏指数 (MBI)评分均明显提高，tDCS联合FES治疗在更短的时间内即达到了改善上肢功能的治疗效果。这可能和tDCS联合FES治疗能够更好的改善偏瘫肢体异常协同收缩模式有关。基于神经成像技术的脑可塑性机制研究进一步显示，治疗前后低频波动振幅（ALFF）对比，额上回、额中回、运动前皮层、中央前回、辅助运动区、顶上回ALFF显著增加；局部一致性（ReHo）对比，治疗后额中回、中央前回的局部一致性显著增加。本项目提示了tDCS与FES联合治疗是一种可改善脑卒中患者偏瘫上肢功能的有效模式，并为该联合治疗模式提供了脑网络影像学依据。