中文摘要：

目的采肘扩散张量成像探索Ⅱ型糖尿病患者脑部早期潜在隐匿性损伤。方法对16例Ⅱ型糖尿病患者及16名健康志愿者进行脑部扩散张量成像及脑部结构像扫捕，对全脑平均ADC图及各向异性分数（FA）冈进行基于体素的全脑分析。统计学方法采用协方差分析（年龄为协变量）。结果Ⅱ型糖尿病患者双侧距状回，有侧颞上回、额中回、前扣带回及中扣带回、枕下回，及左侧舌回、额叶岛盖部、梭状回和海马旁回（体素数目为176～3125，P值均〈0．01）的局部脑部灰质及右侧颞中回、舌回、额中回、距状回和顶上回白质，及左侧额叶岛盖白质（体素数目为200～781，P值均〈0．01）平均ADC值较对照组显著增高。全脑FA值分析提示Ⅱ型糖尿病患者较正常对照脑部灰质FA值减低区域主要位于左侧丘脑、双侧尾状核及右侧楔叶皮层（体素数目为210～1402，P值均〈0．01）；脑部白质FA值减低区域主要位于右侧楔叶白质及胼胝体体部（体素数目分别为206、253，P值均〈0．01）。结论Ⅱ型糖尿病患者脑部早期隐匿性的变化可表现为双侧大脑局部脑实质ADC值增高及FA值的减低，基于体素的DTI可以作为Ⅱ型糖尿病患者早期隐匿性脑部损害评估的有效丁具。

英文摘要：

Objective To evaluate early occult brain damage by diffusion tensor imaging in patients with type II diabetes mellitus. Methods High resolution three-dimensional T1-weighted fast spoiled gradient recalled echo MRI images and diffusion tensor imaging were obtained from 16 patients with type II diabetes mellitus （T2DM） and 16 normal controls （NC）. Average apparent diffusion coefficient （ADC） map and fractional anisotropy （FA） map were calculated and analyzed with voxel-based analysis. Analysis of eovarianee was performed to compare ADC and FA between T2DM and NC. Results Increased ADC values of gray matter were demonstrated in right superior temporal gyrus, middle frontal gyrus, anterior eingulate gyms, middle cingulate gyms, inferior occipital gyms, and left lingual gyrus, operculum orbitale, fusiform gyms and parahippocampal gyms in T2DM （voxel numbers in clusters were 176--3125,P 〈 0.01 ）. And increased ADC values of white matter were demonstrated in the regions of right middle temporal lobe, linual lobe, middle frontal lobe, calcarine gyms, superior parietal lobe, and left operculum orbitale in T2DM patients compared with NC （ voxel numbers in clusters were 200--781, P 〈 0. 01 ）. Decreased FA values of gray matter were mainly located in left thalamus, bilateral caudate nuclei and right cuneus in T2DM（voxel numbers in clusters were 210--1402,P 〈 0. 01 ）. Decreased FA values of white matter were demonstrated in the regions of right cuneus and the body of corpus callosum in T2DM （ voxel numbers in clusters were 206,253 ,P 〈 0. 01 ）. Conclusions The occult brain damage is demonstrated as increased ADC values and decreased FA values in regional brain parenchyma in type II diabetes mellitus. Voxel-based analysis of diffusion tensor indices may be a simple and effective tool for the evaluation of occult brain damage in type II diabetes mellitus.