Ahn Young Hwan, You Sung H, Randolph Marilys, Kim Seong Ho, Ahn Sang Ho, Byun Woo Mok, Yang Dong Suk, Jang Sung Ho
Department of Neurosurgery, School of Medicine, Ajou University, Suwon, Republic of Korea.
NeuroRehabilitation. 2006;21(3):233-7.
Combined functional MRI (fMRI) and diffusion tensor tractography (DTT) imaging provides a powerful vehicle for the investigation of motor recovery mechanisms. Using this combined method, we investigated the motor recovery mechanism in patients with pontine infarct.
We evaluated six healthy control subjects and two patients with pontine infarct at 6 months from onset. fMRI was performed at 1.5 T with timed hand grasp-release movements. For DTT, we used each of the 32 noncollinear diffusion-sensitizing gradients. Three-dimensional reconstructions of the fiber tracts were obtained with FA <0.3, angle >45 degrees as termination criteria.
fMRI data revealed activation only in the contralateral primary sensorimotor cortex during movement of either hand. DTI findings from controls and the unaffected hemisphere of the patients showed that the corticospinal tract descended through the known corticospinal tract pathway. However, the tracts of the affected hemisphere in the patients were observed to pass along peri-infarct areas (patient 1: lateral, patient 2: posterior) in the pons.
It seems that the peri-infarct areas compensate for corticospinal tract damage at the pons; this may be one mechanism of motor recovery for patients with pontine infarct.
功能磁共振成像（fMRI）与弥散张量纤维束成像（DTT）相结合，为研究运动恢复机制提供了有力手段。运用这种联合方法，我们对脑桥梗死患者的运动恢复机制进行了研究。
我们评估了6名健康对照者和2例脑桥梗死患者，均为起病6个月时。fMRI在1.5T条件下进行，采用定时的手部抓握-松开动作。对于DTT，我们使用了32个非共线弥散敏感梯度中的每一个。以FA<0.3、角度>45度作为终止标准，获得纤维束的三维重建图像。
fMRI数据显示，在任何一只手运动时，仅对侧初级感觉运动皮层有激活。对照组以及患者未受影响半球的DTI结果显示，皮质脊髓束通过已知的皮质脊髓束路径下行。然而，观察到患者受影响半球的纤维束沿脑桥梗死灶周围区域走行（患者1：外侧，患者2：后侧）。
梗死灶周围区域似乎可代偿脑桥处皮质脊髓束的损伤；这可能是脑桥梗死患者运动恢复的一种机制。
