基于结构与静息态功能MRI神经网络分析对肝性脑病发作后持续性神经认知功能损害的机制研究

项目名称： 基于结构与静息态功能MRI神经网络分析对肝性脑病发作后持续性神经认知功能损害的机制研究

项目编号： No.81501450

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 陈华俊

作者单位： 南京医科大学

项目金额： 18万元

中文摘要： 肝性脑病（HE）是肝硬化常见并发症，及时诊治可使HE临床症状缓解、消失。但最新研究表明HE发作后患者会出现轻微而持续性神经认知功能损害，集中表现为执行控制能力及学习能力下降，并预示HE复发风险，关系到疾病的防治。而目前关于这些认知损害产生的特征性脑神经机制尚未清楚，无法为临床诊治提供有力证据。我们预实验发现HE发作后患者存在脑结构与功能网络拓扑学属性改变，有可能是认知损害的重要机制之一。在预实验及既往对HE患者脑部MRI研究的基础上，本课题以肝硬化患者为对象，基于DTI与静息态fMRI分别构建全脑结构、功能网络，应用图论分析，对比有HE发作史者、无HE发作史者、以及健康者脑网络拓扑学属性，检测全局网络效率的改变并定位相关异常脑区，分析脑网络异常与HE后认知障碍相关性，以从新的视角探寻HE后持续性认知损害的机制，有助于阐明HE演变规律，发掘潜在影像学标志，为HE诊治及预防提供新的理论依据。

中文关键词： 肝性脑病；认知障碍；弥散张量成像；静息态；磁共振成像

英文摘要： Hepatic encephalopathy (HE) is a frequent complication in cirrhotic patients. Recent studies demonstrate the persistence of cognitive impairments even after resolution of HE, such as deficits in learning and control-executive function, which predict higher risk of HE recurrence. However, it remains unknown about mechanisms underlying these cognitive impairments so far. Our primary finding is that patients with previous HE episode develop aberrant brain topological characteristics, which may be associated with the persistent cognitive impairments. Therefore, this study will involve 30 cirrhotic patients with previous HE, 30 cirrhotic patients without previous HE, and 30 age- and sex-matched healthy controls. The cognitive assessments, DTI and resting-state fMRI are administrated to each subject. Brain white-matter structural connection is depicted with DTI data; while functional connectivity is measured by temporal correlation based on resting-state fMRI data. Graph theory-based analyses are performed to characterize global and nodal properties of brain networks, which then are compared across three groups. The correlation analyses are also performed to examine the relationship between altered brain network properties and cognitive impairments. This study will improve our understanding about mechanisms underlying persistent cognitive deficits after HE, which would be useful in identifying potent biomarkers for treatment and secondary prophylaxis of HE.

英文关键词： Hepatic encephalopathy;Cognitive impairment;Diffusion tensor imaging;Resting state;Magnetic resonance imaging