中文摘要：

目的 探讨轻度认知损害者（MCI）和阿尔茨海默病（AD）患者多模态磁共振成像特征与认知功能的关系.方法 共纳入9例遗忘型MCI,15例轻度AD及11例正常对照,以简明精神状况检查（MMSE）和认知功能筛查测验（CASI）评估总体认知功能,对高分辨率结构像进行基于体素形态学分析（VBM）,测量扩散张量成像（DTI）图像、各脑区白质各向异性比值（FA）和平均表观弥散系数（ADC）,分析脑结构萎缩及白质DTI指标与认知评分的相关性.结果 MMSE和CASI评分与颞、额、顶、扣带回、海马旁回等结构灰质体积改变呈正相关（P〈0.001）,MMSE和CASI总分与颞、顶叶以及海马旁回的FA值呈正相关,与ADC值呈负相关（P〈0.05）.结论 MCI和AD患者认知功能与颞、顶、海马旁回等脑区萎缩及白质微观结构损伤密切相关,多模态影像技术可作为认知损害脑机制研究的重要技术手段.

英文摘要：

Objective To investigate the association of multi-modality neuroimaging features and cognitive function in mild cognitive impairment （MCI） and Alzheimer＇s disease （AD）.Methods Nine individuals with amnestic MCI （aMCI）, fifteen patients with mild probable AD, and eleven age-controlled cognitively normal controls （NC） were recruited.All participants were administered with mini-mental status examination （MMSE） and Cognitive assessment screening instrument （CASI） to assess general cognitive function.Optimized voxel-based morphometry （ VBM ） was used for the analysis with 3-D high resolution anatomical images.Values of fractional anisotropy （FA） and mean apparent diffusivity coefficient （ADC） were measured from different brain regions on diffusion-tensor images （ DTI） .The relationship between structural atrophy and DTI-based measurements in the selected brain regions was examined.Results The scores of MMSE and CASI were correlated with the volumetric changes in such areas as temporal, frontal and parietal lobes, and cingulate gyrus and hippocampal gyrus （P 〈0.001）.The scores of MMSE and CASI were positively correlated with FA values, and negatively with ADC values in the white-matter-affected regions including temporal, frontal, parietal lobes, cingulate gyrus, and parahippocampal gyrus （P 〈 0.05）.Conclusions Cognitive decline was associated with atrophy and white matter microstructural alterations in temporal, frontal, parietal lobes, cingulate gyrus, and parahippocampal gyrus in MCI and AD. Multi-modality imaging technique may be important in elucidating the brain mechanism of cognitive impairment.