健侧顶叶皮层参与卒中急性期脑功能重组:fMRI研究

目的利用功能性磁共振成像(fMRI)技术探讨缺血性卒中急性期的脑功能重组特点。资料与方法采用被动单指运动任务，对4例急性皮质下梗死患者和4名正常人进行fMRI研究，比较正常人与卒中患者之问以及每个卒中患者之问fMRI结果的异同。结果正常人被动单指运动激活对侧感觉运动皮层(SMC)、后顶叶皮层(PPC)和双侧辅助运动区(SMA)。卒中患者健手运动fMRI结果基本同正常人；患手运动时，除1例同(健)侧SMC、SMA、前运动皮层(PMC)激活外，4例均呈现出同侧PPC的激活。结论首次应用fMRI技术采用恒定的被动刺激探讨卒中急性期患者运动恢复的神经机制，结果显示了正常人和脑卒中患者之间fMRI结果的显著差异，反映了卒中急性期脑功能的重组情况，也为卒中急性期健侧半球PPC中介运动恢复提供了新的实验依据。

Evidence for Involvement of Unaffected Parietal Cortex in Brain Reorganization from Acute Stroke: A fMRI Study

Objective To investigate brain reorganization after acute ischemic stroke using functional MRI (fMRI).Materials and Methods 4 patients with unilateral acute subcortical infarction and four normal subjects were scanned during passive index finger movement within 14 days after stroke. Results of brain activations were compared between normal and patient subjects.Results In normal subjects, activation in contralateral sensorimotor cortex (SMC), posterior parietal cortex (PPC) and bilateral supplementary area (SMA) were observed during passive movements. While similar results were recorded in patients during unaffected hand movement. Ipsilateral PPC in all 4 patients were activated during the paretic hand movements, and ipsilateral SMC, SMA and premotor cortex (PMC) in only one patient.Conclusion For the first time, we explored mechanism of motor recovery in acute ischemic stroke using fMRI through prolonged constant passive stimulation. The results of our study showed significant difference in fMRI between normal subjects and patients which reflected brain reorganization from acute stroke. This article offered novel experimental evidence for the role of PPC in unaffected hemisphere in motor recovery following acute stroke.