运动区占位性病变患者皮质功能重组的功能磁共振成像研究

An fMRI study of the motor cortex reorganization in patients with space-occupying lesions

目的:采用功能磁共振成像(fMRI)技术研究脑运动皮质区占位性病变患者手功能区的重组状况,分析其相应的病理生理变化。方法:选择12例临床症状较轻的运动皮质区占位性病变患者,采用组块设计的方法,双手分别行静止对指任务,在GEsigna1.5T磁共振成像仪下行数据采集,SPM99进行数据后处理,结果采用单样本分析。结果:所有患者患侧脑激活区与健侧相比存在一种或多种差异,表现在:①患侧激活脑区移位,但无主运动区(M1)激活减弱(10例)。包括患侧M1区移位4例,患侧M1区和辅助运动区(SMA)均移位4例,SMA区移位2例;②患侧手指(病变对侧)动作任务时,SMA区激活较健侧任务时增强(4例)或减弱(2例);③患侧M1区激活减弱(1例)。结论:本组患者运动皮质的功能重组有两种表现形式:患侧脑区的移位代偿、患侧主运动区辅助运动区间代偿。fMRI可直观地观察功能区的分布,对指导神经外科手术具有重要的临床意义。

Objective: To study the cortex reorganization using fMRI and analyze its relevant pathophysiology of the patients with space-occupying lesions situated in motor area. Methods: Data was obtained from twelve patients with little or without motor deficit using BOLD-fMRI technique at GE-signa 1.5 T MRI system.A block-paradigm was applied with the both side fingers holding still or oppositing respectively.Data processing was carried out using SPM99.Result was analyzed with Single-subject model. Results: Compared to the unaffected side motor cortex activation,the affected side cortex activation exhibited at least one kind of difference in all the patients, which showed:①Functional displacement presented in ten patients but without weakening of the affected M1(four cases in the affected M1, four in both affected M1 and SMA,and two in SMA)②Activation of SMA was stronger (four patients) or weaker(two patients)when the affected contralateral fingers opposition than when the ipsilateral fingers movement.③Functional activation within the affected M1 was decreased(one patient). Conclusion: The result suggests that two pattens of motor cortex reorganization present in patients with space-occupying lesions situated in motor area:the affected side activation displace but exist compensation,and there is compensation between the affected M1 and SMA. FMRI can exhibit the activation of motor cortex straight and has potential as a tool to direct the neurosurgery.