2型糖尿病患者大脑皮层变薄及胰岛素治疗恢复效应观察

Study of cortical thinning in the patients with type 2 diabetes mellitus and the recovering effect of theinsuline therapy

目的利用全脑皮层厚度分析技术分析2型糖尿病患者皮层厚度的变化以及胰岛素治疗对大脑皮层厚度的作用。方法对11名健康志愿者及11例2型糖尿病患者在基线（胰岛素治疗前）及随访水平（胰岛素治疗1年后）进行三维脑结构像扫描，并采用最近距离法计算皮层厚度图，并利用自动感兴趣法计算各脑区平均皮层厚度。统计学方法采用配对t检验。结果2型糖尿病患者双侧大脑及全脑平均平层厚度均小于对照组（P〈0．05）；胰岛素治疗1年后，右侧大脑及全脑平均皮层厚度均大于随访前平均皮层厚度（P〈0．05），左侧大脑平均皮层厚度差异无统计学意义（P〉0．05）。各脑区平均皮层厚度分析提示2型糖尿病患者随访水平平均皮层厚度增加区域主要位于左侧内侧额叶眶回、双侧额叶岛盖部、右侧缘上回、右侧枕外侧回、左侧距状回、右侧梭状回、双侧颞下回、颞中回、左侧前扣带回尾侧、双侧内嗅皮层、左侧海马旁回、右侧岛叶及右侧前扣带回吻侧。结论2型糖尿病患者大脑皮层较正常人显著变薄，胰岛素治疗可使其皮层厚度广泛增厚，具体机制有待于进一步研究。

Objective To explore the cortical thickness changes in the patients with type 2 diabetes mellitus and the effects of the insuline therapy on the brain using whole brain cortical thickness mapping. Methods High resolution three-dimensional Tl-weighted fast spoiled gradient recalled echo MRI images were obtained from 11 normal controls and 11 patients with type II diabetes at baseline level （before insulin therapy） and follow-up level （ after insulin therapy for 1 year）. The whole brain cortical thickness map was calculated by the closest point methods. The cortical thickness of each brain region was calculated using the automatic region of interest. The paired t test was performed for the mean cortical thickness. Results The mean cortical thickness of bilateral hemisphere and whole brain was decreased in the patients with type 2 diabetes mellitus compared with normal controls （P 〈 0. 05）. After insuline therapy 1 year, the mean cortical thickness of right hemisphere and whole brain at follow-up was significantly increased compared with that at baseline （P 〈 0. 05 ）, and the mean cortial thickness of left hemisphere showed no significant difference between baseline and follow-up （P 〉 0. 05）. Mean cortical thickness over each brain region demonstratd that increased cortical thickness were mainly located in the left medial orbitofrontal gyms, bilateral pars opercularis, right supramarginal gyrus, right lateral occipital gyrus, left calcarine gyrus, right fusiform gyrus, bilateral inferior temporal gyri, middle temporal gyri, left caudal anterior cingulate, bilateral entorhinal cortex, left parabippocampal cortex, right insular lobe and right rostral anterior cingulate. Conclusion Cortical thinning was investigated in the patients with type 2 diabetes mellitus compared with normal controls, and wide cortical thickening was demonstrated after insuline therapy for 1 years. The precise mechanism should be further explored.