2型糖尿病患者脑部静息态的功能磁共振成像

Resting-state brain functional magnetic resonance imaging in patients with type 2 diabetes mellitus

目的采用静息态脑功能成像探索2型糖尿病患者早期脑部功能损伤。方法对18名2型糖尿病患者及18名健康志愿者进行脑部静息态功能成像及脑部结构像扫描,计算全脑局部一致性(regional homogeneity,ReHo)、低频振幅(amplitude of low frequency fluctuation,ALFF)及双侧海马、后扣带回的功能连接。统计学方法采用成组t检验。结果 2型糖尿病患者较正常对照ReHo减低脑区主要位于右侧丘脑、海马、嗅皮质及左侧壳核,ALFF减低脑区主要位于左侧额中回及右侧缘上回、枕中回。2型糖尿病患者较正常对照海马功能连接主要表现双侧海马之间功能连接的减低,但与其他脑区之间无显著功能连接减低区域;双侧后扣带回与其他脑区之间未见显著功能连接减低区域。结论 2型糖尿病患者早期脑部静息态脑功能主要表现为局部脑区ReHo及ALFF的减低,双侧海马之间功能连接的减低,双侧后扣带回功能连接无显著改变。

Objective To evaluate early occult brain functional damage in patients with type 2 diabetes meUitus using resting-state functional magnetic resonance imaging （MRI）. Methods High-resolution three-dimensional Tl-weighted fast spoiled gradient recalled echo MRI and resting-state functional MRI images were obtained from 18 patients with type 2 diabetes meUitus and 18 normal control subjects. Regional homogeneity （ReHo） map, amplitude of low-frequency fluctuation （ALFF） map, and functional connectivity map of the bilateral hippocampus and posterior cingulate gyrus were calculated and voxel-based analysis was performed using two-sample t-test. Results In type 2 diabetic patients, decreased ReHo was deteted in the right thalamus, hippocampus, olfactory cortex and left putamen as compared with the normal controls. The decreased ALFF was found mainly in the left middle frontal gyrus, right supramarginal gyms and middle occipital gyrus in the diabetic patients. The patients showed reduced functional connectivity between the bilateral hippocampus but not between the bilateral posterior gyrus and the other brain regions. Conclusion The occult brain damage is featured by decreased ReHo and ALFF in multiple brain regions and reduced functional connectivity between the bilateral hippocampus in type 2 diabetic patients.