【摘要】 目的使用静息态功能磁共振成像(rs-fMRI)观察认知正常和存在轻度认知障碍(MCI)的脑白质疏松(LA)患者的静息态脑网络(RSNs),进一步使用格兰杰因果分析法(GCA)分析网络之间的功能连接,并与正常人进行比较。方法选取年龄40～80岁的LA-MCI患者34例,LA认知正常患者15例,正常人33例。行rs-fMRI扫描,独立成分分析法分离功能脑网络,两样本t检验比较各组间脑网络活动性。GCA分析相关RSNs之间的功能连接关系。结果共得到8个RSNs:默认网络、运动网络、内侧视觉网络、外侧视觉网络、右侧记忆网络、左侧记忆网络、听觉网络和执行网络,三组间不同脑区激活程度不同。三组内部不同脑网络间功能连接模式存在一定差异。结论 LA患者脑网络成分随着疾病进展而变化,RSNs早期出现网络成分变化及激活程度下降;随着认知障碍程度增加,激活程度进行性下降,并出现脑网络之间连接方向和连接强度的变化和重建。更多还原

【Abstract】 Objective To compare the difference in resting state networks among leukoaraiosis(LA) patients with or without mild cognitive impairment, and healthy controls, as well as the functional connectivity under Granger causality analysis(GCA).Methods Subjects aged 40 to 80 years, including 34 LA-MCI patients, 15 LA patients with normal cognition and 33 healthy controls, accepted resting-state functional magnetic resonance imaging. Independent component analysis was used to separate functional brain networks, and difference of activation was determined with two sample ttest. GCA was used to analyze effective connectivity of these functional networks.Results Eight resting state networks were obtained, including default mode network, motor network, medial visual network, lateral visual network, right-memory network, left-memory network, auditory network and executive network. Activation was different among three groups. Effective connectivity of RSNs was also different among three groups.Conclusion Components of the resting state networks keep changing as LA progressing. Activation decreases as patients’ cognition impaired. The direction and strength of connections remodel.更多还原