卒中早期手指被动运动的脑功能磁共振成像研究

Functional MRI of finger passive flexion-extension movement at the early stage of stroke

目的应用扩散张量成像及BOLDfMRI技术观察卒中早期手指被动运动时大脑半球相关区域血氧水平的变化情况。方法采用1.5TMR成像系统对6名早期卒中患者进行BOLDfMRI及扩散张量成像,采用手指被动屈伸运动作为fMRI的刺激任务。结果在锥体束中断时,卒中早期健手运动时激活双侧SMC区,患手运动可激活对侧半球后顶叶皮层及同侧SMC区;锥体束较完整时健手运动时激活对侧SMC区,患手运动激活双侧SMC区、双侧后顶叶皮层。结论卒中早期可能发生运动功能通路的重构,但锥体束不同损伤情况下运动功能恢复可能存在不同的机制。DTI与fMRI联合应用将是监测和研究脑卒中后恢复的有用工具。

Objective To observe the cerebral activation during finger passive flexiomextension movement by using diffu sion tensor imaging （DTI） and functional MRI （fMRI） at the early stage of stroke. Methods Six stroke patients were examined by DTI and fMRI at 1.5 T, and fMRI was performed using a finger passive flexion-extension movement paradigm. Results fMRI showed that the bilateral primary sensorimotor cortex （SMC） were activated by passive movements of the unaffected hand, the ipsilateral SMC and contralateral posterior parietal cortex were activated by movements of the affected hand when the pyramidal tract disrupted. Conversely, the bilateral SMC were activated by passive movements of the unaffected hand, only the contralateral SMC and posterior parietal cortex were activated by passive movements of the affected hand when the pyramidal tract was not damage. Conclusion Motor pathways reorganization occurs with motor recovery at the early stage of stroke, and there may be different patterns of cortex reorganization with the different extent of pyramidal tract damage. Combined DTI and fMRI is useful for monitoring the motor recovery after stroke.