Abstract:

Objective  To evaluate the changes of resting-state network connection of leukoaraiosis (LA) patients with or without mild cognitive impairment (MCI) by using functional magnetic resonance imaging (fMRI) and to explore the value of resting-state fMRI in the early diagnosis of LA.  Methods  A total of 49 LA patients were divided into 2 groups: LA with MCI (LA-MCI, N = 34) and LA with non-MCI (LA-NMCI, N = 15) based on Clinical Dementia Rating Scale (CDR). Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), Hamilton Depression Rating Scale-17 Items (HAMD-17) and Hamilton Anxiety Rating Scale-14 Items (HAMA-14) were used to evaluate cognitive function, depression and anxiety symptoms of all patients and 33 normal controls. Resting-state fMRI was used to explore the brain network functional connection.  Results  The age of LA-MCI patients were significantly older than that of normal controls (P = 0.003). The MMSE (P = 0.001, 0.000) and MoCA (P = 0.001, 0.000) scores in LA-MCI group were significantly higher than those in LA-NMCI group and control group. There was decreased functional connection of nuclei within the salience network in LA-MCI group compared with normal control group. Besides, the connection between salience network and default mode network (DMN) was enhanced, while connection between salience network and central executive network (CEN) was weakened. In LA-NMCI group, there was decreased functional connection of nuclei within the salience network compared with normal control group. Besides, the connection between salience network and DMN was enhanced, while the connection between salience network and CEN was weakened.  Conclusions  There was significant difference in resting-state fMRI brain network functional connection between normal controls and LA patients with or without MCI. Presumably it could account for the pathophysiological mechanism of LA-related cognitive impairment to some extent.

Key words: Leukoaraiosis, Cognition disorders, Magnetic resonance imaging

摘要：

目的 采用fMRI研究脑白质疏松症伴或不伴轻度认知损害患者静息态脑网络功能连接，探讨静息态fMRI 对脑白质疏松症的早期诊断价值。方法 共49 例脑白质疏松症患者根据临床痴呆评价量表评分分为脑白质疏松症伴轻度认知损害组（LA-MCI组，34 例）和脑白质疏松症不伴轻度认知损害组（LA-NMCI 组，15 例），采用简易智能状态检查量表、蒙特利尔认知评价量表、汉密尔顿抑郁量表17 项和汉密尔顿焦虑量表14 项评价认知功能、抑郁和焦虑症状，静息态fMRI 研究脑网络功能连接。结果 LA-MCI组患者年龄大于正常对照组（P = 0.003），MMSE（P = 0.001，0.000）和MoCA（P = 0.001，0.000）评分高于LA-NMCI 组和正常对照组。与正常对照组相比，LA-MCI 组患者突显网络内部核团功能连接减弱，突显网络对脑默认网络核团的功能连接呈增强趋势、对中央执行网络的功能连接呈减弱趋势；LA-NMCI组患者突显网络内部核团功能连接减弱，突显网络对脑默认网络核团的功能连接呈增强趋势、对中央执行网络核团的功能连接呈减弱趋势。结论 脑白质疏松症伴或不伴轻度认知损害患者静息态激活脑区与正常人群存在差异，可以在一定程度上解释脑白质疏松症伴认知功能障碍的病理生理学机制。

关键词: 脑白质疏松症, 认知障碍, 磁共振成像