Qiu Yage, Yu Ling, Ge Xin, Sun Yawen, Wang Yao, Wu Xiaowei, Xu Qun, Zhou Yan, Xu Jianrong
Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Department of Neurology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.
Front Aging Neurosci. 2021 Feb 18;13:605900. doi: 10.3389/fnagi.2021.605900. eCollection 2021.
Loss of white matter (WM) integrity contributes to subcortical vascular mild cognitive impairment (svMCI). Diffusion tensor imaging (DTI) has revealed damage beyond the area of WM hyperintensity (WMH) including in normal-appearing WM (NAWM); however, the functional significance of this observation is unclear. To answer this question, in this study we investigated the relationship between microstructural changes in the WMH penumbra (WMH-P) and cognitive function in patients with svMCI by regional tract-based analysis. A total of 111 patients with svMCI and 72 patients with subcortical ischemic vascular disease (SIVD) without cognitive impairment (controls) underwent DTI and neuropsychological assessment. WMH burden was determined before computing mean values of fractional anisotropy (FA) and mean diffusivity (MD) within WMHs and WMH-Ps. Pearson's partial correlations were used to assess the relationship between measurements showing significant intergroup differences and composite -scores representing global cognitive function. Multiple linear regression analysis was carried out to determine the best model for predicting composite -scores. We found that WMH burden in the genu, body, and splenium of the corpus callosum (GCC, BCC, and SCC respectively); bilateral anterior, superior, and posterior corona radiata; left sagittal stratum was significantly higher in the svMCI group than in the control group ( < 0.05). The WMH burden of the GCC, BCC, SCC, and bilateral anterior corona radiata was negatively correlated with composite -scores. Among diffusion parameters showing significant differences across the 10 WM regions, mean FA values of WMH and WMH-P of the BCC were correlated with composite -scores in svMCI patients. The results of the multiple linear regression analysis showed that the FA of WMH-P of the BCC and WMH burden of the SCC and GCC were independent predictors of composite -score, with the FA of WMH-P of the BCC making the largest contribution. These findings indicate that disruption of the CC microstructure-especially the WMH-P of the BCC-may contribute to the cognitive deficits associated with SIVD.
白质（WM）完整性的丧失会导致皮质下血管性轻度认知障碍（svMCI）。扩散张量成像（DTI）显示，除了WM高信号（WMH）区域（包括正常外观的白质（NAWM））之外，还存在损伤；然而，这一观察结果的功能意义尚不清楚。为了回答这个问题，在本研究中，我们通过基于区域束的分析，研究了svMCI患者WMH半暗带（WMH-P）的微观结构变化与认知功能之间的关系。共有111例svMCI患者和72例无认知障碍的皮质下缺血性血管病（SIVD）患者（对照组）接受了DTI和神经心理学评估。在计算WMH和WMH-P内的分数各向异性（FA）和平均扩散率（MD）的平均值之前，先确定WMH负担。采用Pearson偏相关分析来评估显示出显著组间差异的测量值与代表整体认知功能的综合评分之间的关系。进行多元线性回归分析以确定预测综合评分的最佳模型。我们发现，svMCI组胼胝体膝部、体部和压部（分别为GCC、BCC和SCC）；双侧前、上和后放射冠；左侧矢状层的WMH负担显著高于对照组（<0.05）。GCC、BCC、SCC和双侧前放射冠的WMH负担与综合评分呈负相关。在10个WM区域显示出显著差异的扩散参数中，BCC的WMH和WMH-P的平均FA值与svMCI患者的综合评分相关。多元线性回归分析结果显示，BCC的WMH-P的FA以及SCC和GCC的WMH负担是综合评分的独立预测因素，其中BCC的WMH-P的FA贡献最大。这些发现表明，胼胝体微观结构的破坏，尤其是BCC的WMH-P，可能导致与SIVD相关的认知缺陷。
