轻度认知障碍患者功能脑网络模块分离研究

Modularity Segregation of the Brain Functional Networks in Mild Cognitive Impairment

目的 探索功能脑网络模块分离在轻度认知障碍(MCI)患者中的改变及其应用价值。资料与方法 2018年8月—2021年6月于广州市第一人民医院体检中心招募28例MCI患者和15例健康对照者,对所有受试者采集静息态功能磁共振图像,利用GRETNA软件对数据进行预处理及功能网络构建,然后利用图论分析方法在网络稀疏度为0.2时,计算模块化指数、节点参与系数及平均参与系数,比较组间差异,并采用Bonferroni多重比较校正方法对结果进行校正。结果 与健康对照组比较,MCI组的模块化指数较低(t=-2.30,P=0.03),平均参与系数差异无统计学意义(t=1.495,P=0.14);MCI组左侧补充运动区、右侧枕上回、左侧中央旁小叶、左侧丘脑、右侧颞横回及右侧颞上回脑区的节点参与系数均高于健康对照组(t=2.29、2.73、2.57、2.40、2.64、2.07,P均<0.05)。结论 MCI患者的模块分离程度较健康对照者减低,主要累及视觉、听觉和躯体感觉运动脑区,这可能成为MCI活体功能影像图谱的潜在生物标志物。

Purpose To investigate the changes and application values of modular segregation of functional brain network in patients with mild cognitive impairment(MCI).Materials and Methods From August 2018 to June 2021,a sample of 28 MCI patients and 15 normal controls was included from the physical examination center of Guangzhou First People's Hospital.The resting-state functional MRI data of all subjects in the two groups were collected,then the functional MRI data were preprocessed.The GRETNA software was applied to construct the large-scale brain networks and calculate graph theoretical metrics at the sparsity threshold of 0.2.The parameters contained the modularity of a network,participation coefficient,and average participation coefficient.The statistical comparisons of theses parameters were performed,and Bonferroni multiple comparisons were used to correct the results.Results The modularity of the network had a significant reduction relative to normal control group(t=-2.30,P=0.03).The average participation coefficient had no significant difference between the two groups(t=1.495,P=0.14).However,the participation coefficient of the left supplements motor area,the right superior occipital gyrus,the left paracentral lobule,the left thalamus,the right heschl gyrus,the right superior temporal gyrus in the MCI group were significantly higher than those in the normal control group(t=2.29,2.73,2.57,2.40,2.64,2.07,all P<0.05).Conclusion The modular segregation in the MCI patients is declined relative to that in the normal control group,mainly involved visual,auditory and motor brain areas,which may become a potential biomarker for functional image atlas in vivo of MCI.