运用功能磁共振成像探讨中央沟区肿瘤对运动皮层功能的影响

 【目的】运用功能磁共振成像（fMRI）的方法探索中央沟区肿瘤对运动皮层的影响。【方法】46例颅内中央沟区肿瘤完成了常规和fMRI检查，包括转移瘤10例、胶质瘤19例、脑膜瘤8例、动静脉畸形3例、血管瘤4例、蛛网膜囊肿2例。15例正常人共完成22次手运动删RI作为对照组。删RI扫描采用平面回波成像加快速梯度回波序列，手运动任务采用组块设计方法，五指对掌开合，频率为1～2Hz。【结果】肿瘤距同侧SMl1em以内对SMl的影响比距1em以上者明显。肿瘤同侧SMl激活率低，但对侧SM1及其他非主要运动区激活出现率差别不大。距同侧SM12cm内的恶性肿瘤对SM1影响比良性肿瘤明显。SM1激活率低．且对侧SMA、CMA激活率升高。与正常组的比较亦显示出距SM12em内的恶性肿瘤对SM1激活影响明显，SM1激活率明显减低。【结论】中央沟区肿瘤对运动皮层区的影响主要取决于肿瘤距同侧SM1的距离和肿瘤的良恶性，其影响以同侧SMI激活减低为主，恶性肿瘤可见对侧SMA、CMA激活代偿增加。

Affection of Tumors Near Central Sulcus on Motor Cortex: Functional MRI Study

Objective To explore affection of tumors near the central sulcus on motor cortex by functional magnetic resonance imaging(MRI).Methods Forty-six patients with brain tumor near the central sulcus were examinated by routine and functional MRI.Among them,10 were metastases,19 were gliomas,8 were meningiomas,3 were arterial-venal malformation(AVM),4 were hemangiomas,and 2 were arachnoid cysts.Total 22 hand movement functional MRI in 15 healthy peoples were performed as comparing group.The functional MRI was performed using FFE-EPI sequence.The block design was used in this study.The task was given with five fingers open and close in a rate of 1-2 HZ.Results The affection to the sensorimotor cortex(SM1) was more obvious for tumors within 1 cm from ipsilateral SM1 than over 1 cm from ipsilateral SM1.The occurring rate of activation in ipsilateral SM1 was lower,but there was not obvious difference in occurring rates of activation in contralateral SM1 and other non-primary motor cortex.The affection to the SM1 was more obvious for malignant tumors than for benign tumors within 2 cm from ipsilateral SM1,in which the occurring rate of activation in ipsilateral SM1 was lower,but the occurring rate of activation was raised in the contralateral supplementary motor area(SMA) and cingulated motor area(CMA).The obvious affection to the SM1 was also shown in malignant tumors within 2 cm from ipsilateral SM1 comparing the normal group,the occurring rate of activation in ipsilateral SM1 decreased.Conclusion The affection to motor cortex for tumors near the central sulcus depend mainly on the distance between tumor and ipsilateral SM1 and property of tumors.The affection mainly includes decrease of ipsilateral SM1 activation and complemental increase of contralateral SMA and CMA activations in malignant tumors.