Recent studies found that a loss of motor function following corticospinal tract (CST) damage can, to some extent, be restored. Few studies, however, examine how space-occupying lesions in the brain motor area may affect the contralateral CTS structure and function. We performed a simulation of intracranial space-occupying lesions in the brain motor area by implanting of balloons into the brains of the two healthy macaques. Diffusion tensor imaging (DTI) was performed on the macaques' brains four times to measure the FA values of the contralateral CST operative area. The results showed that on the day of balloon implantation, the FA values had no obvious effect, but with time the effect increased, becoming increasingly apparent one week after removing the balloons. Experimental results demonstrated that this model was both feasible and reliable. After the simulated space-occupying lesions occurred in the brain motor area, DTI showed a compensatory response of the contralateral CTS, which remained for a short period of time even after the lesions were removed. This result suggests that the contralateral CST may then also contribute to recovery of limb function.
因皮质脊髓束 (corticospinal tract, CST) 损伤而造成的运动功能丧失可得到一定恢复, 但关于大脑运动区占位性病变对健侧CST结构功能影响的研究却相对较少。该研究采用两只健康猕猴行球囊置入术建立大脑运动区占位性病变模型, 行4次磁共振弥散张量成像 (diffusion tensor imaging, DTI) 扫描, 检测手术区对侧CST的FA值 (“各向异性”值), 发现球囊置入术后当天, 对侧CST的FA值无明显变化, 但随时间的延长升高, 球囊取出术后一周更为明显。实验表明该模型可行、可靠, 从DTI观察到病变健侧CST出现代偿, 即使占位解除短期内这一作用仍明显, 提示健侧CST共同参与瘫痪肢体功能的恢复。
Keywords: Corticospinal tract; Diffusion tensor imaging; Macaque; Simulation model of intracranial space-occupying lesions.