作用于小脑的低频rTMS对后循环缺血卒中患者的下肢运动功能及皮层兴奋性的影响

目的探究作用于小脑的重复经颅磁刺激（rTMS）对后循环缺血性卒中（PCS）患者下肢运动功能的临床疗效和大脑皮层兴奋性变化，并初步探讨其作用机制。 方法收集宜昌市第一人民医院康复医学科自2019年1月至12月收治的27例PCS患者，按照随机数字表法分为治疗组（13例）与对照组（14例）。2组患者均接受常规物理治疗，治疗组再此基础上给予rTMS治疗，刺激部位为健侧小脑（体表定位为枕骨粗隆旁开3 cm、下移1 cm处），重复频率为1 Hz，80%静息运动阈值（RMT），刺激数为1600个，每天1次，连续4周；对照组的刺激参数与治疗组一样，但仅有声音提示。分别在治疗前、治疗4周后采用Fugl-Meyer运动量表（FMA）、Fugl-Meyer平衡量表（FMBS）和威斯康星步态量表（WGS）对患者进行功能评估，同时检测患者的RMT、皮层运动诱发电位（MEP）波幅的变化，并将运动功能改善与皮层兴奋性的变化进行相关性分析。 结果治疗4周后，2组患者的FMA、FMBS及WGS评分均有不同程度的提高，RMT降低、MEP波幅增高（P<0.05）；与对照组相比，治疗组RMT和MEP波幅的改变更明显（P<0.05）。进一步研究发现，FMBS的改善程度与RMT的变化呈负相关（P<0.05）。 结论作用于小脑的低频rTMS能有效改善后循环卒中患者的下肢运动功能，其机制可能与其增加了大脑的皮层兴奋性有关。

Effect of cerebellar low frequency rTMS on lower lamb motor function and cortical excitability in patients with posterior circulation stroke

ObjectiveTo observe the effects of repetitive transcranial magnetic stimulation (rTMS) on lower extremity motor function and cerebral cortex excitability in patients with posterior circulation stroke(PCS), and to explore its mechanism. MethodsTwenty-seven stroke patients with PCS, admitted to Rehabilitation Medicine Department of The First People’s Hospital of Yichang from January to December 2019, were randomly divided into treatment group (n=13) and control group (n=14). Patients in both groups received routine physiotherapy, and the patients in the treatment group were treated with rTMS. The stimulation site was the contralateral cerebellum (the body surface was located at the site of 3 cm adjacent to the trochanter of the occipital bone and moved downward to 1 cm), the repetition rate was 80% resting motor threshold (RMT), and the number of stimuli was 1600, once a day for 4 consecutive weeks. The stimulation parameters of the control group were the same as those of the treatment group, but only sound cues. Fugl-Meyer motor scale (FMA), Fugl-Meyer balance scale (FMBS) and Wisconsin gait scale (WGS) walking function were used to evaluate the function of the patients before and 4 weeks after treatment. At the same time, the changes of RMT and cortical motor evoked potential (MEP) amplitude were measured, and the correlation between the improvement of motor function and cortical excitability was analyzed. ResultsAfter 4 weeks of treatment, the scores of FMA, FMBS and WGS increased, RMT decreased and MEP amplitude increased in the two groups (P<0.05), and the changes of RMT and MEP amplitudes in the treatment group were more obvious than those in the control group (P<0.05). The negative correlation between the improvement of FMBS and the change of RMT (P<0.05). ConclusionLow frequency rTMS acting on the cerebellum can effectively improve the balance function of patients with PCS, and its mechanism may be that it increases the cortical excitability of the brain.