Department of CT/MRI, Institute of Rehabilitation and Imaging of Brain Function, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, 637000, China.
Department of Medical Imaging, Southwest Medical University, Luzhou, 646000, Luzhou, China.
Acta Neurol Belg. 2021 Dec;121(6):1435-1447. doi: 10.1007/s13760-020-01322-5. Epub 2020 Mar 13.
Previous diffusion tensor imaging (DTI) studies have reported that both mild cognitive impairment (MCI) and Alzheimer's disease (AD) revealed microstructural changes [fractional anisotropy (FA)]. However, these results were not conclusive. The purpose of this meta-analysis was to identify the consistent FA alterations and the differences between MCI and AD. Case-control studies investigating MCI and AD using FA were searched in the online databases. The quantitative FA value of cognition-related brain regions was extracted and the standardized mean difference (SMD) with 95% confidence interval (CI) was calculated using fixed or random effect models. Twenty six studies with a total of 1,021 patients were included in this meta-analysis. Significantly decreased FA in patients with AD were identified in the left frontal lobe, corpus callosum (CC), fornix, hippocampus (HP), cingulate gyrus (CG), cingulate bundle (CB), uncinate fasciculus (UF), superior longitudinal fasciculus(SLF), the inferior fronto-occipital fascicles (IFOF), and the inferior longitudinal fasciculus(ILF) relative to MCI in this meta-analysis. This study provides objective and quantitative evidence that AD is associated with FA alteration within left frontal lobe, CC, FX, HP, CG, CB, and UF may suggest the key regions of the process from MCI to AD.
先前的弥散张量成像（DTI）研究报告称，轻度认知障碍（MCI）和阿尔茨海默病（AD）都显示出微观结构变化[各向异性分数（FA）]。然而，这些结果并不确定。本荟萃分析的目的是确定 MCI 和 AD 之间一致的 FA 改变和差异。在在线数据库中搜索了使用 FA 研究 MCI 和 AD 的病例对照研究。提取与认知相关脑区的定量 FA 值，并使用固定或随机效应模型计算标准化均数差（SMD）及其 95%置信区间（CI）。本荟萃分析共纳入 26 项研究，共 1021 例患者。与 MCI 相比，AD 患者的左侧额叶、胼胝体（CC）、穹窿、海马（HP）、扣带回（CG）、扣带束（CB）、钩束（UF）、上纵束（SLF）、下额枕束（IFOF）和下纵束（ILF）的 FA 明显降低。本研究提供了客观和定量的证据，表明 AD 与左额叶、CC、FX、HP、CG、CB 和 UF 内的 FA 改变有关，这可能提示了从 MCI 到 AD 的过程中的关键区域。
