运动想象训练促进脑卒中患者上肢运动功能恢复的功能磁共振研究

摘要 目的：利用功能磁共振（fMRI）研究脑卒中患者运动想象训练后上肢功能重组潜在的脑重塑机制，为临床脑卒中患者的康复治疗提供一定的理论基础。 方法：选择9例脑卒中偏瘫患者，进行运动想象训练每周5次，每次约30min，共4周，并进行常规康复训练。应用Fugl-Meyer上肢运动功能量表（FMA-UL）分别在治疗前和治疗后4周评估患者的上肢运动功能。在4周康复干预前后对患者进行患手被动握拳任务下的fMRI检查，采用组块设计，利用SPM8软件进行数据处理，采用感兴趣区（ROI）的个体化分析，统计各ROI区的脑皮质激活情况，比较干预前后对侧感觉运动区（cSMC）的激活变化，分析脑卒中患者的脑重塑模式。 结果：4周运动想象干预后脑卒中患者的FM-UL评分从（22.44±11.59）分提高到（39.78±14.03）分（P=0.011）。比较干预前后两次fMRI检查脑皮质SMC区的激活情况，发现9例脑卒中患者的功能恢复呈现出两种不同的皮质重塑模式：一种模式为募集激活，即大部分患者第二次fMRI检查，患手被动任务下cSMC的激活增加（有6例患者）；另一种模式是集中激活，即小部分患者第二次fMRI检查，患手被动任务下cSMC的激活虽然是减少的，但其偏侧指数（LI-SMC）却是显著增加的（有3例患者）。 结论：运动想象训练可改善脑卒中患者的上肢运动功能，经过4周干预后脑卒中患者存在损伤同侧SMC区的募集激活和集中激活两种脑重塑模式，随着患者上肢功能的恢复，脑重塑机制逐渐倾向于损伤侧SMC的激活。

The effects of motor imagery training on upper-extremity functional reorganization in stroke patients: a fMRI study

Abstract Objective: To measure the efficacy of motor imagery training (MIT) in improving stroke patients' upper-extremity functional outcomes and to find the possible cortical reorganization patterns associated with the improvement of motor function with functional magnetic resonance imaging (fMRI) response during a passive hand task. Method: Nine stroke patients with stable, pure and motor deficits were enrolled. All patients received motor imagery training for 4 weeks (30 minutes a day, 5 days a week) and conventional rehabilitation therapy. Functional evaluation was assessed by the upper extremity of Fugl-Meyer assessment (FMA-UL) before treatment and 4 weeks after treatment. fMRI was also administered to assess cortical activation changes in regions of interest (ROIs) that included the primary and secondary motor and sensory areas while the patients executed a passive fist clutch task at the two time points before and after 4-week interventions. Result: After the interventions, FM-UL scores of the 9 stroke patients dramatically increased (22.44±11.59 vs 39.78±14.03, P=0.011). There were two types of cortical reorganization patterns existed in the patients. One pattern consisted of persistent growth in activation in contralateral sensorimotor cortex(cSMC) for most patients (6 patients), and the other pattern consisted of focusing of activation in cSMC with increasing of the laterality index of SMC (LI-SMC) for a small portion of patients (3 patients). Conclusion: This study indicated that, for the stroke patients with upper-extremity impairments, a 4-week regimen of motor imagery training resulted in functional improvement in upper-extremity. These interventions may elicit plastic changes; i.e., the possible two cortical reorganization patterns in the brain: increasing recruitment and focusing recruitment in cSMC. When the patients improved their functions, they mainly chose the cortical reorganization which was dominated by the activation in cSMC.