脑卒中后偏瘫手运动功能恢复的功能性磁共振成像研究

The fMRI study of motor recovery of the hemiplegic hand after stroke

目的应用功能磁共振成像(fMRI)技术探索脑卒中后运动功能恢复的脑代偿形式和机制。方法选择25例脑卒中患者作为患者组,其中男16例,女9例;年龄28～75岁,平均54.1岁;进行fMRI检查时间最短为发病2周,最长为60个月。同时选择15例正常人作为对照组进行fMRI检查,其中男11例,女4例,年龄35～69岁,平均48.6岁。结果对照组双侧手分别运动时,均在对侧SM1区产生激活,12例右手运动时激活同侧SMl区(12/15),6例左手运动时激活同侧SMI区(6/7)。SMl激活区呈斑片状或不规则状高信号。各非主要运动区亦有一定比例的激活。患者组均在对侧SM1区产生激活,同侧SM1区则有22例产生激活,激活体积多数以对侧较大,LI值为正值。右侧患手对侧SM1激活平均体积及LI值与正常组相近,同侧SM1平均激活体积大于正常组,LI值小于正常组,差异有统计学意义(P<0.05)。左侧患手的双侧SM1平均激活体积及LI值与正常组比较,差异均无统计学意义。PM、SMA、CMA激活的出现率有不同程度增高,以对侧明显。结论脑卒中后处于康复进程中者,患手对侧SM1体积已恢复到正常水平,同侧SM1仍有代偿现象。双侧的PM、SMA和CMA也有代偿表现。

Objective To explore the compensatory mechanisms of brain in the recovery of stroke patients. Methods fMRI examination was performed on 15 healthy persons including 11 men and 4 women （mean age 48.6 years; range 36 ～69 years）, and 25 stroke patients including 16 men and 9 women （mean age 54.1 years; range 28 ～75 years）. The fMRI was performed from 2 weeks to 60 months after onset of stroke. Results In the normal group, the activations were seen in all contralateral SM1 with both hand movement, in 12 （ 12/15 ） ipsilateral SM1 with right hand movement, in 6 （6/7） ipsilateral SM1 with left hand movement. The SM1 activations appear as spotlike or irregular shape with high signal intensity. The activations were also seen in non-primary motor cortices. In the patient group, the activations were seen in all contralateral SMI and 22 ipsilateral SM1 of 25 paretic hand movement. The volume of activation was larger in contralateral SMI than that in ipsilateral SM1 in most cases. LI values were positive. The average volume of contralateral SM1 activation caused by right paretic hand movement was similar to that of normal right hand movement, but larger in ipsilateral SM1 activation with significant statistical difference. The LI value was smaller than that of the normal group and had also significant statistical difference. There are no statistical differences in the average volumes in the contralaleral, the ipsilateral SM1 activation, in the LI value caused by left paretic hand movement and by normal left hand movement. The occurring rates of activation increased in PM, SMA, CMA in comparing right or left paretic hand movement to normal hand movement, especially in the ipsilateral side. Conclusion For stroke patients, the contralateral SM1 volume of paretic hand reached to normal level. There were still compensatory activations in ipsilateral SM1. The compensatory activations were also seen in both sides of PM, SMA and CMA.