MRI定量观察阿尔茨海默病患者全脑皮质表面积

目的 观察阿尔茨海默病(AD)患者全脑皮质表面积改变。 方法 对25例AD患者(AD组)和30名健康志愿(对照组)者行全脑3.0T MR检查,应用三维磁化准备快速梯度回波序列和高分辨扫描技术采集三维解剖数据,采用Freesurfer软件分析所得大脑精细立体结构像。 结果 AD组全脑皮质表面积呈现双向变化:双侧额中回尾侧、额上回、中央前回、颞下回、颞中回、颞上回、颞横回、海马、海马旁回、岛叶皮层表面积较对照组增大,双侧顶下小叶、顶上小叶、扣带回狭部、后扣带回、前扣带回嘴侧皮层表面积较对照组减小,差异均有统计学意义(P均<0.05)。 结论 AD患者大脑多个部位存在皮层表面积改变,前额叶、颞叶、海马及海马旁回以代偿扩张为主,后顶叶和扣带回以萎缩为主,提示AD具有特定的脑皮质形态结构改变和发病机制。

Quantitative MRI observation of whole brain cortical surface areas in Alzheimer disease

Objective To investigate the change of whole brain cortical areas in Alzheimer disease (AD) patients. Methods Twenty-five AD patients and 30 age, gender and education matched normal control subjects underwent MRI of the whole brain using 3.0T MR system. Subtile three-dimensional brain images were obtained using MPRAGE sequence and high resolution scanning technique, and were processed and analyzed with Freesurfer software. Results Compared with controls, the changes of cortical areas in AD were bidirectional. Increased bilateral cortical area was seen in caudal middle frontal gyrus, rostral superior frontal gyrus, precentral gyrus, inferior, middle, superior and transverse temporal gyrus, hippocampus, parahippocampal gyrus and insula (P<0.05), while decreased bilateral cortical area was seen in superior and inferior parietal lobe, isthmus, posterior and anterior cingulate gyrus (P<0.05). Conclusion Changes of multiple cortical surface areas existed in AD patients. The prefrontal lobe, temporal lobe, hippocampus and parahippocampal gyrus mainly manifested as compensatory enlargement, while the posterior parietal and cingulate gyrus mainly manifested as atrophy, suggesting that AD has special cortex morphous changes and pathogenesis.