DTI及DTT在评价急性大脑中动脉供血区脑梗死患者预后中的应用

Application of DTI and DTT in the evaluation of prognosis in patients with acute middle cerebral artery infarction

目的利用核磁共振弥散张量成像(DTI)及白质纤维束成像(DTT)技术评价急性大脑中动脉供血区脑梗死患者皮质脊髓束(CST)损伤程度与预后的关系。方法对20例急性大脑中动脉供血区脑梗死的患者行常规1.5T DTI和DTT检查,此检查均在发病72h内进行。测量梗死灶区与对侧镜像区、梗死灶边缘区、双侧大脑脚的FA值及ADC值。据CST受损程度分为3级。对20例患者分别行美国国立卫生研究院卒中评分(NIHSS)及简式Fug-Meye运动功能评分(FMS)。将CST分级与发病3个月时NIHSS及FMS评分进行相关性分析,评价CST损伤程度与患者临床预后的相关性。结果梗死灶FA值及ADC值较健侧均有不同程度下降,差异均具有统计学意义(P<0.001),表明急性期缺血缺氧已造成病灶组织不同程度的损伤。CST受损程度与运动功能障碍分级成高度负相关性(r=-0.843,P<0.001),即CST受损越严重,运动功能分级越低,运动功能障碍程度越重,预后越差。CST受损程度与神经功能恢复情况成高度正相关性(r=0.819,P<0.001),即CST受损越严重,神经功能评分越低,神经功能预后越差。结论 DTI及DTT为定量分析急性大脑中动脉供血区病灶组织及CST损伤程度提供了途径,为早期准确判断临床预后及指导临床治疗提供了可靠依据。

Objective To investigate the correlation between different damage degrees of CST and prognosis in patients with acute middle cerebral artery infarction by using MR diffusion tensor imaging（DTI） and diffusion tensor tractography（DTT）. Methods Twenty patients with middle cerebral artery infarction were prospectively examined with 1.5T diffusion tensor imaging and diffusion tensor tractography within a 72-hour mean interval onset. The fractional anisotropy（FA） and the apparent diffusion coefficient（ADC） in ischemic lesion and the oppsite area in nonaffected hemisphere, the fringe area of infarcts, cerebral peduncle were measured. According to the extent of CST destruction, the affacted CST was divided into three grades The twenty patients were graded by NIHSS and FMS. Spearman correlation analysis was applied to reveal the relationships between the extent of CST destruction and clinical prognosis. Results FA and ADC values notably decreased in infraction lesions verses non-affected hemisphere（P〈0.001）, which revealed that the tissue in infarction lesions had been damaged in different extent. Negative correlation was found between the extent of CST destruction and motor dysfunction grading according to FMS（r=-0.843, P〈0.001）, which revealed that the more serious CST was damaged, the lower motor dysfunction grading, the heavier degree of motor impairment, the worse prognosis. Positive correlation was found between the extent of CST destruction and recovery of neurological function according to NIHSS（r=0.819, P〈0.001）, which revealed that the more serious CST was damaged, the lower neurological function score, the worse prognosis of neurological function. Conclusion DTI and DTT provide a way for the quantitative analysis of acute middle cerebral artery territory lesions and the degree of CST damage, and provide reliable basis for early accurately judge the clinical prognosis and guide clinical treatment.