DTI和DTT评估脑缺血性卒中所致运动功能损伤康复的研究

Study of DTI and DTT on Impairment of Cortical Spinal Tract in Patients with Cerebral Ischemia

目的利用磁共振扩散张量成像(DTI)及扩散张量纤维束成像(DTT)评价脑缺血性卒中所致皮质脊髓束(CST)损伤程度及与运动功能的关系。资料与方法对15例急性期大脑中动脉供血区缺血性脑卒中患者行常规MRI、DTI和DTT检查,对数据进行离线后处理,采用dTV.II软件处理,获得各向异性分数(FA)图及方向编码彩色图,并重组双侧CST3D纤维束图。对梗死区及健侧相应区域白质进行FA测量。采用Brunnstorm标准判断脑卒中患者患手肌力。结果脑卒中患者梗死区FA值显著低于健侧,两侧相比差异有统计学意义(t=-6.3333,P<0.0000)。病变侧CST表现为受压、变形、移位和中断,CST损伤程度与患手肌力级别经检验呈显著负相关关系(rs=-0.97361,P<0.0001),CST的损伤情况与运动功能的恢复有良好的相关。结论CST损伤严重程度与运动功能的恢复相关,DTI和DTT对观察CST的损害程度、预测恢复程度、指导临床康复治疗具有重要的价值。

Objective To study the diffusion anisotropic features of white matter fibers of cerebral ischemic patients by using MR diffusion tensor imaging （DTI）and diffusion tensor tractography （DTT）, and evaluate the relationship between the impairment degree of cortical spinal tract（CST） and muscular strength. Materials and Methods 15 patients with acute cerebral ischemic stroke received MR, DTI and DTr. For imaging processing, the software of DTV-Ⅱ was used, fractional anisotropy maps, directionally encoded color maps and 3D tractography of bilateral CST of all patients were obtained. Fractional anisotropy were measured and compared between infarction lesions and corresponding contralateral normal regions. Hand motor function ability was evaluated with Brunstorm criteria. Results In stroke patients, the FA value in infarct area of white matter was significant lower than that in normal hemisphere （ paired test, t = - 6. 3333, P 〈 0.0000）. DTI and DTT showed that the CST was compression, displacement, translocation, and break. The configuration of the CST was closely negative correlated with motor recovery （ spearmen test, rs = - 0. 97361, P 〈 0. 0001 ）. Conclusion In acute cerebral ischemic stroke, the impairment severity of CST is related to muscle strength, therefore, DTI and DTT have important value in clinical management and prognosis.