血压正常2型糖尿病患者大脑微结构改变的VBM及TBSS研究

Brain microstructure alteration in type 2 diabetes mellitus without hypertension by VBM and TBSS analysis

目的:基于纤维束示踪空间统计分析(TBSS)研究大脑扩散张量成像(DTI)图像,观察血压正常2型糖尿病(T2DM)患者脑白质微结构的改变,并探讨双侧大脑半球间的脑白质改变方法:本研究纳入20名血压正常的T2DM患者及20名年龄、性别匹配的正常对照。采用3.0T磁共振扫描仪采集大脑结构像和DTI数据,应用基于体素的形态学分析(VBM)和TBSS方法比较两组受试者间的大脑体积,白质各向异性分数(FA)和平均扩散系数(MD)值的差异,以及两组受试者左右侧大脑半球DTI参数比值的差异。结果:与正常对照相比,血压正常的T2DM患者大脑体积未见显著减小(P>0.05);大脑白质完整性广泛受损,尤以胼胝体膝部、左侧内囊前肢、辐射冠前上部、扣带束及上额-枕束为著;右侧上辐射冠、后辐射冠、扣带束及上纵束FA值和MD值均有改变(P<0.05);双侧大脑半球上辐射冠MD值升高,以左侧升高更为显著(P<0.05)。结论:血压正常的T2DM患者双侧大脑半球白质微结构广泛损伤,尤以左侧为著,TBSS分析有助于早期检出上述改变。

Objective;To investigate the cerebral microstructure alteration in type 2 diabetes mellitus（T2DM）patients without hypertension using tract-based spatial statistics（TBSS） and to investigate asymmetry in bilateral hemisphere.Methods：Twenty T2 DM patients without hypertension and 20 age-,sex-matched healthy controls were recruited in this study.Structural image and DTI data were acquired by using 3.OT MR scanner.Voxel-based morphometry（VBM） and TBSS analysis were used to investigate the changes of brain volume,white matter FA and MD values in T2 DM patients compared with those in control group,and to investigate the difference of DTI ratio between left and right hemisphere.Results：Compared with healthy controls,there was no significant decrease of brain volume in T2 DM patients without hypertension（P〉0.05）.However,significant changes of FA and MD value were found in genu of corpus callosum,left anterior limb of internal capsule,anterior and superior corona radiate,cingulum and superior frontooccipital fasciculus（P〈0.05）.There was significant increase of MD value in bilateral superior corona radiate,especially in left hemisphere（P〈0.05）.Conclusion;Widespread white matter microstructure disruptions were found in T2 DM patients without hypertension,especially in the left hemisphere.TBSS analysis was helpful in early detection of the white matter microstructure alterations in T2 DM patients without hypertension.