Cai Luhui, Liang Yanli, Huang Huanjian, Zhou Xia, Zheng Jinou
Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
Department of Neurology, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, China.
Neuroimage Clin. 2020;25:102189. doi: 10.1016/j.nicl.2020.102189. Epub 2020 Jan 23.
Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis showing severe neuropsychiatric symptoms is the most common type of autoimmune encephalitis. However, the corresponding standard clinical magnetic resonance imaging (MRI) presents normal or atypical in the majority of patients with anti-NMDAR encephalitis. Here, this study aimed to investigate the alterations in brain functional activity in patients with anti-NMDAR encephalitis and whether these alterations contributed to cognition and mood disorders.
Seventeen patients with anti-NMDAR encephalitis and eighteen gender, age and education-matched healthy controls were recruited. All participants underwent neuropsychological tests (including Montreal Cognitive Assessment (MoCA), Hamilton Anxiety Scale (HAMA), and Hamilton Depression Scale (HAMD)) and resting-state functional MRI. MRI data was firstly analyzed by amplitude of low-frequency fluctuation (ALFF), and brain regions with altered ALFF between groups were selected as regions of interest for the further functional connectivity (FC) analysis. Correlation analyses were performed to investigate the associations between brain dysfunction and neuropsychological performance.
Relative to the healthy controls, patients with anti-NMDAR encephalitis performed inferiorly in the MoCA score, and showed anxiety and depression disorders with higher HAMA and HAMD scores (all p < 0.05). In the brain functional activity analysis, the patients showed decreased ALFF values in the bilateral posterior cingulate gyrus, left precuneus, and bilateral cerebellum (false- discovery- rate corrected, p < 0.05). Furthermore, relative to the control group, the patients showed significantly increased FC between the left posterior cingulate cortex (PCC) and the bilateral lingual gyrus, right calcarine, right cuneus, also between the right PCC and the right fusiform gyrus, bilateral lingual gyrus, left calcarine, left cuneus, and right posterior central gyrus (false- discovery- rate corrected, p < 0.05). FC strength between the left posterior cingulate gyrus and right cuneus, and between the right posterior cingulate gyrus and left cuneus were both positively correlated with MoCA memory scores (r = 0.485, p = 0.048; r = 0.550, p = 0.022).
The present study highlight that decreased spontaneous neural activities and abnormal FC exhibited in the patients with anti-NMDAR encephalitis, which may participate in the process of cognition and emotion deficits. These results may help to elucidate the clinical radiological contradictions in anti-NMDAR encephalitis and contribute to deeper understanding of the pathophysiological mechanism of the disease.
表现出严重神经精神症状的抗N-甲基-D-天冬氨酸受体（NMDAR）脑炎是最常见的自身免疫性脑炎类型。然而，在大多数抗NMDAR脑炎患者中，相应的标准临床磁共振成像（MRI）表现正常或不典型。在此，本研究旨在调查抗NMDAR脑炎患者脑功能活动的改变，以及这些改变是否导致认知和情绪障碍。
招募了17例抗NMDAR脑炎患者和18名性别、年龄和教育程度匹配的健康对照者。所有参与者均接受神经心理学测试（包括蒙特利尔认知评估（MoCA）、汉密尔顿焦虑量表（HAMA）和汉密尔顿抑郁量表（HAMD））以及静息态功能MRI检查。首先通过低频振幅（ALFF）分析MRI数据，将两组间ALFF值发生改变的脑区选为感兴趣区进行进一步的功能连接（FC）分析。进行相关性分析以研究脑功能障碍与神经心理学表现之间的关联。
与健康对照者相比，抗NMDAR脑炎患者的MoCA评分较低，且HAMA和HAMD评分较高，表现出焦虑和抑郁障碍（均p<0.05）。在脑功能活动分析中，患者双侧后扣带回、左侧楔前叶和双侧小脑的ALFF值降低（错误发现率校正，p<0.05）。此外，与对照组相比，患者左侧后扣带回皮质（PCC）与双侧舌回、右侧距状裂、右侧楔叶之间，以及右侧PCC与右侧梭状回、双侧舌回、左侧距状裂、左侧楔叶和右侧中央后回之间的FC显著增加（错误发现率校正，p<0.05）。左侧后扣带回与右侧楔叶之间以及右侧后扣带回与左侧楔叶之间的FC强度均与MoCA记忆评分呈正相关（r=0.485，p=0.048；r=0.550，p=0.022）。
本研究强调抗NMDAR脑炎患者存在自发神经活动降低和FC异常，这可能参与了认知和情感缺陷的过程。这些结果可能有助于阐明抗NMDAR脑炎的临床影像学矛盾，并有助于更深入地了解该疾病的病理生理机制。
