Objective To analyze the clinical feature of executive function impairment in subcortical ischemic cerebrovascular disease(SIVD) and to investigate the correlation between executive function and cerebral white matter lesions(WML) and white matter microstructure change. Furthermore,to explore the related factors of white matter with executive function in SIVD patients. Methods Twenty-four SIVD patients and fourteen normal control subjects(NC) were evaluated with stroop colour words test(CWT), trail making test(TMT) and block design test(BDT) to assess the executive function. Twenty-four patients were divided into vascular dementia ( VD, n = 12)and vascular cognitive impairment no dementia ( VCIND, n= 12) groups. Age-related white matter change rating scale (ARWMCrs) was used to measure and located the WML by cranial MRI scanning. DTI images were acquired qualitatively. Fractional anisotropy ( FA ) and mean diffusivity (MD) of normal-appearing white matter(NAWM) in splenium of the corpus callosum, frontal, parietal, temporal and occipital lobes were determined. Correlation analysis was used to investigate the relationship between executive function and DTI parameters. Results ( 1 ) Compared with those of NC group, the score of VD patients were decreased in each targets of neuropsychological tests. The scores of VCIND patients were less than those of healthy controls in CDT and BDT tests and the time of TMT was longer. The difference between two groups was statistically significant (P ＜ 0. 05 ). (2) The scores of WML were ( 12. 820 ± 3.573 ) and ( 10. 500 ± 2. 953 ) in VD and VCIND groups ( P ＜0. 05 ). The MD values of splenium of corpus callosum were increased in two groups ( P ＜ 0. 05 ). Decreased FA values of NAWM on the frontal, right temporal, parietal and right occipital lobes were demonstrated in VD patients, as well as of the left frontal and parietal in VCIND patients. There was significant difference compared with those of NC group ( P ＜0. 05 ). ( 3 ) The MRI and DTI parameters related with executive function in SIVD patients were FA values of NAWM in left frontal lobe,both temporal lobes and right parietal lobe and MD values of splenium of corpus callosum( P ＜ 0. 05 ). Conclusions ( 1 ) The executive function impairment in patients with SIVD could be associated with the degree of WML. (2) The select microstructural white matter lesions in patients with SIVD could be showed with DTI, which are normal in cranial MRL (3) The decreased FA and increased MD of several white matter regions are associated with CWT, TMT and BDT in SIVD group. It suggests that microstructural white matter impairment might be used for evaluating executive function decline.%目的 探讨皮质下缺血性脑血管病(SIVD)执行功能损害、MRI脑白质病变和DTI脑白质的微结构变化及其临床相关因素.方法 应用Stroop色词测验(CWT)、连线测验(TMT) 和积木测试(BDT)评价24例SIVD患者和14例认知正常老年人的执行功能,其中SIVD患者分为痴呆(VD)组12例,认知障碍无痴呆(VCIND)组12例;依据年龄相关白质改变的评分方法(ARWMCrs) 测量常规MRI上白质病变程度,同时应用DTI分别测定额、颞、顶、枕叶及胼胝体压部白质正常区的各向异性分数(FA)和平均扩散率(MD)值,分析各影像学测量指标与执行功能的相关性.结果 (1)与健康对照组比较,VD组执行功能三项测验均显著减退,VCIND组BDJ评分降低,TMT时间延长,差异有统计学意义(P<0.05);(2)与对照组相比较,VD、VCIND组白质病变评分增高,分别为12.820±3.573、10.500±2.953(P＜0.05);胼胝体压部MD值均升高,具有统计学差异(P＜0.05);VD患者双额叶、右颞叶、右枕叶、双顶叶及胼胝体压部FA值下降(P＜0.05);VCIND组左额叶、双顶叶白质FA值下降(P＜0.05);(3)与SIVD患者执行功能相关的影像学指标有:左额叶、双颞叶、右顶叶白质正常区FA值、胼胝体压部MD值(P＜0.05).结论 (1)SIVD患者存在执行功能障碍,与其脑白质病变程度可能有关;(2)DTI可以显示SIVD患者常规MRI无法显示的脑白质选择性微结构损害;(3)SIVD患者的多个脑白质区FA及MD与CWT、TMT和BDT存在相关性,提示白质微结构的损害可能反映执行功能的下降.
展开▼
