基于DTI探讨脑小血管病患者脑白质微结构损伤与认知功能障碍的相关性

目的应用DTI技术探讨脑小血管病(c SVD)患者常规扫描表现正常白质(NAWM)区微结构改变,及其与认识功能障碍的相关性。方法对23例c SVD患者及13例条件相匹配的正常志愿者进行常规MRI及DTI序列检查并完成Mo CA评分,后处理测量双侧额叶、顶叶、半卵圆中心、胼胝体膝部及压部NAWM区的FA值及ADC值,比较c SVD组与对照组间的差异,并进一步分析c SVD组FA值及ADC值与Mo CA评分的相关性。结果 c SVD组双侧额顶叶FA值较对照组减低,ADC值升高,双侧半卵圆中心FA值较对照组减低,其余两组间区别无统计学差异。c SVD患者双侧额叶FA值下降最明显(右侧(0.354±0.051)vs(0.398±0.027),P=0.0 1,左侧(0.3 6 5±0.0 5 3)v s0.405±0.035,P=0.00)。双侧额叶白质的FA值与Mo CA评分呈正相关(右侧额叶:r=0.43,P=0.01;左侧额叶:r=0.50,P=0.02),ADC值与Mo CA评分呈负相关,(右侧额叶:r=-0.40,P=0.03;左侧额叶:r=-0.37,P=0.00);其余部位FA值及ADC值与Mo CA评分无统计学意义的相关性。结论 DTI能反映c SVD患者早期隐匿性脑白质损伤,额叶白质DTI指标改变一定程度可反映认知功能受损程度。

The Study of Correlation Between Diffusion Tensor Imaging and Cognitive Impairment in Cerebral Small Vessel Disease

Objective To explore the occult damage of normal appearing white matter (NAWM) in patients with small vessel disease(cSVD) by using diffusion tensor imaging (DTI)technology, and its relationship with cognitive impairment.Methods Twenty-three patients with cSVD and thirteen matched volunteers all received conventional MR scanning, DTI and montperllier cognitive function scale (MoCA) examination. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were measured symmetrically and compared among the two groups. Pearsoncorrelation analysis was used to determine the correlation between the FA,ADC and MoCA score in cSVD group. Results FA value on bilateral frontal and apical NAWM in cSVD group were lower than control group, and ADC value were higher than control group.The decreased FA value on bilateral centrum semiovale was demonstrated in cSVD group. FA value on bilateral frontal lobe decreased obviously, right (0.354±0.051)vs(0.398±0.027), P=0.01, left (0.365±0.053)vs(0.405±0.035),P=0.00).In cSVD group, the FA value of bilateral frontal NAWM were positively correlated with MoCA score (right: r=0.43, P=0.01, left: r=0.50, P=0.02), and the ADC value of bilateral frontal NAWM were negatively correlated with MoCA score(right: r=-0.40, P=0.03, left: r=-0.37, P=0.00).Conclusion The occult damage of normal appearing white matter (NAWM) can be detected using DTI. And DTI can reflect the severity of cognitive impairment in patients with cSVD.