基于VBM-Dartel方法对阿兹海默症和轻度认知功能障碍患者的脑组织结构分析

Analysis of Structural Organization of the Human Brain for Alzheimer's Disease and Mild Cognitive Impairment: A Voxel-based Morphometric Study Using DARTEL

目的:利用MRI图像研究轻度认知功能障碍(MCI)、轻度阿尔茨海默病(AD)患者和健康对照组(HC)两两组间灰质和白质体积改变的特点。方法:利用DARTEL算法对14例AD患者(AD组)、21例MCI患者(MCI组)及23例健康对照组(HC组)的MRI图像(数据均来于于ADNI数据库)进行预处理,再对MCI组、AD组和HC组的全脑灰质和白质体积进行基于体素的统计学比较分析。结果:灰质变化:与HC组比较,AD组的双侧海马、海马旁回、杏仁核、丘脑、颞中回、尾状核及右侧岛叶、梭状回、前扣带皮层、舌回、内嗅皮层、左侧豆状壳核和顶下小叶等结构灰质体积萎缩。MCI组右侧海马、海马旁回、杏仁核、楔前叶、额上回、双侧额中回和豆状壳核等结构的灰质体积萎缩。AD组相较于MCI组在右侧海马、丘脑、楔叶的灰质体积萎缩。白质变化:与HC组比较,AD组双侧Extra-Nuclear、Sub-Gyral、胼胝体、前扣带回和右侧海马旁回白质体积萎缩。MCI组双侧海马旁回、右侧丘脑、Extra-Nuclear和左侧梭状回白质体积萎缩。AD组相较于MCI组在双侧Sub-Gyral、右侧前扣带回、左侧中央后回白质体积萎缩。结论:基于体素的MRI形态学测量能够客观揭示MCI和AD早期阶段的脑灰质和白质结构萎缩,对于AD的早期诊断和监测MCI向AD的转变提供了很好的依据和方法。

Objective: To study the pattern of volume changes of the whole brain’s gray matter and whiter matter within three groups:Healthy controls, the patients with Alzheimer’s desease (AD), Mild cognitive impairment (MCI). Methods: Fourteen patients with AD, twenty-one patients with MCI and twenty-three normal ageing volun-teers as control subjects from ADNI database are enrolled in the study. Gray volume and White volume difference of the whole brain were assessed using DARTEL method to make voxel-based morphometric comparison within three groups. Results: Changes of gray matter: The volume of bilateral hippocampus, parahippocampal gyrus, amygdala, thalamus, temporal_Mid, caudate, and right insula, fusiform, anterior cingulate cortex, lingual,entorhinal cortex, and left putamen, inferior parietal, etc. in the AD patient group is significantly smaller than that in the control group. The volume of right hippocampus, parahippocampal gyrus, amygdala, precuneus, inferior frontal gyrus, and bilateral middle frontal gyrus, putamen, etc. in the MCI patient group is significantly smaller than that in control group. The volume of right hippocampus , thalamus, Cuneus, etc. in the AD patient group is significantly smaller than that in MCI patient group.Changes of white matter:The volume of bilateral extra-nuclear, sub-gyral, corpus callosum, ante-rior cingulate cortex, and right parahippocampal gyrus, etc. is smaller in the AD patient group is significantly small-er than that in the control group. The volume of right parahippocampal gyrus, thalamus, Extra-Nuclear, and left fusiform, etc. in the MCI patient group is significantly smaller than that in control group. The volume of bilateral sub-gyral, right anterior cingulated, left postcentral etc. in the AD patient group is significantly smaller than that in MCI patient group.Conclusions: VBM can reveal widespread volumetric reduction of gray matter and white matter in AD and MCI with the advantage of objectivity. It is helpful in the early diagnosis of AD and is helpful to monitor the convertion from MCI to probable AD.