不同频率低频重复经颅磁刺激对脑梗死患者上肢功能的影响

The effectiveness of low-frequency transcranial magnetic stimulation for restoring upper limb function after cerebral infarction

目的比较不同频率低频重复经颅磁刺激（rTMS）对脑梗死患者上肢功能的影响。方法50例患者随机分为对照组（10例）、假rTMS组（10例）和rTMS组（30例），rTMS组又按频率分为0．25Hz组、0．5Hz组和0．75Hz组，每组10例。所有患者均给予常规药物治疗和康复训练。假rTMS组另给予假性rTMS治疗；rTMS组则在非受累侧初级运动皮质区（M1区）分别进行不同频率（0．25Hz、0．5Hz、0．75Hz）的rTMS治疗，每周5d，持续4周。分别于治疗前、治疗2周后和治疗4周后对患者进行评定，包括患侧脑区运动诱发电位（MEP）皮质潜伏期、中枢运动传导时间（CMCT）、患侧上肢Fugl—Meyer评分（FMA）、运动力指数（MI）评分和偏瘫上肢功能测试-香港版（FTHUE—HK）评级；将各组所得数据进行统计学分析比较。结果对照组和假rTMS组仅CMCT和FMA在治疗4周后比组内治疗前有明显改善（P〈0．05），2组各时间段各参数间差异均无统计学意义（P〉0．05）。①神经电生理学变化：治疗2周后，0．25Hz组和0．50Hz组的MEP皮质潜伏期较组内治疗前有明显缩短（P〈0．05）且优于同期对照组和同期假rTMS组（P〈0．05）；rTMS组的CMCT亦较组内治疗前明显缩短（P〈0．05），且0．25Hz组和0．50Hz组明显优于同期对照组和同期假rTMS组（P〈0．05）。治疗4周后，各组（除对照组外）MEP皮质潜伏期均优于组内治疗前（P〈0．05）；rTMS组的2项指标均较同期对照组和同期假rTMS组有明显缩短（P〈0．05），且0．25Hz组和0．50Hz组CMCT明显短于0．75Hz组（P〈0．05）。②上肢功能变化：治疗2周后，rTMS组FMA及MI评分均较组内治疗前明显改善（P〈0．05），0．25Hz组和0．50Hz组的FTHUE—HK分级明显优于组内治疗前（P〈0．05），且MI评分明显高于同期对照组和同期假rTMS组（P〈0．05）；治疗4周后，各组FMA和MI评分及rTMS组的FTHUE—HK分级均优于组内治疗前（P〈0．05），0．25Hz组和0．50Hz组的三项指标亦均明显优于同期对照组和同期假rTMS组（P〈0．05），0．75Hz组的MI评分优于对照组和假rTMS组（P〈0．05），0．25Hz组的FTHUE-HK评级亦优于同期0．75Hz组（P〈0．05）。结论非受累侧M1区0．25Hz和0．50Hz的rTMS对提高患侧脑区运动皮质兴奋性和上肢功能的效果最好；0．25Hz的刺激脉冲总数最少，临床治疗可以优先考虑。

Objective To compare the effects of repetitive transcranial magnetic stimulation （rTMS） at various low frequencies on upper limb function after cerebral infarction. Methods Fifty patients were randomly assigned to a control group （10 cases） , a sham rTMS group （10 cases） or an rTMS group which had three sub-groups treated at 0.25 Hz, 0.5 Hz and 0. 75 Hz with 10 cases in each. All of the patients were treated with conventional medical treatment and rehabilitation training. The sham and true rTMS groups received rTMS applied over the M1 area of the unaffected hemisphere, 5 days per week for 4 weeks. Motor evoked potential （MEP） cortical latency, and central motor conduction time （CMCT） were measured and the Fugl- Meyer assessment （FMA）, motricity index （MI） and a Hong Kong functional test for the hemiplegic upper extremity （FTHUE-HK） were evaluated beforehand and at Post 1 after 2 weeks of treatment and Post 2 after 4 weeks of treatment. Results The average CMCT and FMA scores of the control and sham rTMS groups both had improved significantly at Post 2. There was no significant difference in any of the indices between those 2 groups at any time point. At Post 1, the average MEP cortical latencies of the 0.25 Hz and 0.5 Hz subgroups had improved to be significantly better than those of the control and sham rTMS groups. The average CMCTs of the 0.25 Hz and 0.5 Hz rTMS subgroups were significantly shorter after treat- ment, and significantly better than those of the control and sham rTMS groups. At Post 2, the average MEP cortical latency of all groups except the control group showed significant improvement compared with pre-treatment. The 2 indices of the 0.25 Hz and 0.5 Hz subgroups were again significantly shorter than those of the control and sham rTMS groups, and the average CMCTs were significantly better than that of 0.75 Hz subgroup. At Post 1 the average FMA and MI scores of the rTMS subgroups had all improved significantly. In the O. 25 Hz and 0.5 I-Iz subgroups the aver- age MI scores were significantly higher than those of the control and sham rTMS groups. The FTHUE-HK scores of those 2 subgroups had also improved significantly. At Post 2, the average FMA and MI scores of all groups and the FTHUE-HK scores of rTMS group had improved significantly. In the 0. 25 Hz and 0.5 Hz subgroups, all of the indices were significantly better than in the control and sham rTMS groups. The average FTHUE-HK score of the 0.25 Hz subgroup was significantly superior to that of the 0.75 Hz subgroup. In the 0. 75 Hz subgroup the average MI score was significantly higher than in the control and sham rTMS groups. Conclusions rTMS at either 0.25 Hz or 0.5 Hz applied to the unaffected hemisphere provides effective treatment for enhancing the excitability of the motor cortex and the motor function of a paretic upper limb after stroke. Compared with others, the total number of stimulus pulse in 0.25 Hz subgroup was the least, and priority consideration should be given to the frequency of O. 25 Hz when using rTMS in clinical treatment of cerebral infarction.