静息态fMRI观察轻、中度阿尔茨海默病患者脑区功能连接异常

目的 探讨轻、中度阿尔茨海默病（AD）患者全脑功能连接改变及差异。方法 对轻、中度AD患者（轻、中度AD组，各25例）及25名健康体检者（对照组，25名）行静息态fMRI。计算全脑116个脑区的功能连接，以单因素方差分析3组功能连接的差异，采用双样本t检验比较2组间功能连接对的差异。结果 与轻度AD组比较，中度AD组小脑内部及后扣带回与颞叶海马等的功能连接减低，双侧海马间、后扣带回与内侧眶部额上回等脑区功能连接增加。与对照组比较，轻度AD组双侧海马间、小脑蚓部间功能连接增加，后扣带回与颞部海马、眶部额中回及背外侧额上回等脑区功能连接减低；中度AD组表现为小脑内部以及后扣带回与颞部海马、眶部额中回等脑区功能连接减低，后扣带回与内侧眶部额上回以及双侧海马等脑区功能连接增加（P均< 0.05）。结论 中度与轻度AD患者脑功能连接异常存在差异，包括小脑内、双侧海马间连接异常，后扣带回连接减低以及微弱代偿。

Resting-state fMRI observation of abnormal brain functional connectivity in patients with mild andmoderate Alzheimer disease

Objective To explore the changes and differences of brain functional connectivity in patients with mild or moderate clinical Alzheimer disease (AD). Methods Totally 25 patients with mild AD (mild AD group), 25 with moderate AD (moderate AD group) and 25 normal controls (NC group) were enrolled and underwent resting-state fMRI (rs-fMRI). The whole brain cortex was divided into 116 regions, and the functional connection of each brain region was calculated. One-way ANOVA was used to analyze the differences of brain functional connectivity among the three groups. Two sample t-tests were then performed for each two pairs of groups when there was a significant difference. Results Compared with mild AD group, moderate AD group illustrated decreased functional connectivity within the cerebellum, etc. and the posterior cingulated cortex (PCC) connection with hippocampus, etc., and increased functional connectivity between bilateral hippocampus, as well as between PCC and mid-orbital of frontal gyrus, etc.. Compared with NC group, mild AD group illustrated increased functional connectivity in bilateral hippocampus and within the cerebellum vermis, decreased functional connectivity between PCC and the hippocampus, the middle frontal gyrus and the dorsolateral superior frontal gyrus, etc.. Moderate AD group illustrated functional connectivity decreased within the cerebellum, between PCC and hippocampus, the frontal gynecological area, etc., while the functional connectivity increased in the bilateral hippocampus, between PCC and mid-orbital of frontal gyrus, etc. (all P<0.05). Conclusion There are differences in brain functional connectivity between patients with moderate and mild AD, including abnormal connections in the cerebellum and bilateral hippocampus, reduced connections in the posterior cingulate gyrus and weak compensation.