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目的 探讨躯体形式障碍(SFD)患者大脑葡萄糖代谢网络的拓扑变化.方法 用2011年10月至2012年12月期间复旦大学附属华山医院的18例SFD患者[男10例、女8例,年龄(39.5±12.0)岁,病程(3.67±3.20)年;SFD组]、21名健康体格检查者[男13名、女8名,年龄(43.9±8.4)岁;对照组]的18F-脱氧葡萄糖(FDG)PET图像,建立静息状态下2组的大脑葡萄糖代谢网络.使用图论的方法计算脑网络的全局参数(标准化聚类系数、标准化最短路径长度、小世界属性和全局效率)和节点参数(聚类系数和介数中心度).2组脑网络参数间的差异采用重复1000次的置换检验进行统计学分析.根据聚类系数和介数中心度定义前20％ (18/90)的节点为脑网络的关键(Hub)节点,分析SFD患者Hub节点的改变.结果 SFD组患者的脑网络和对照组一样具有小世界属性(σ＞1),但标准化聚类系数、小世界属性和全局效率有降低趋势,标准化最短路径长度有增加趋势(P＞0.05).与对照组相比,SFD患者左侧苍白球、左侧杏仁核、左侧楔前叶和右侧角回的介数中心度明显升高(置换检验,P＜0.05),左侧颞中回和右侧枕上回的介数中心度明显降低(置换检验,P＜0.05);双侧苍白球、双侧丘脑和左侧杏仁核的聚类系数明显降低(置换检验,P＜0.05).SFD组发生改变的Hub节点多数(16/24)位于边缘系统.结论 SFD患者的葡萄糖代谢脑网络拓扑性质发生改变,小世界属性和全局效率呈降低的趋势及Hub节点的改变,导致网络信息传递效率有所降低,功能整合和功能分离的平衡被打破,这为躯体化症状的脑功能异常提供了有效的影像学证据.“,”Objective To observe the alteration of brain glucose metabolic network in patients with somatoform disorders (SFD).Methods 18F-fluorodeoxyglucose (FDG) PET images of 18 SFD patients (10 males 8 females;age:(39.5±12.0) years;illness duration:(3.67±3.20) years) and 21 matched healthy controls (13 males,8 females;age:(43.9±8.4) years) in Huashan Hospital of Fudan University from October 2011 to December 2012 were enrolled to construct the brain glucose metabolic networks for 2 groups (SFD group,control group) respectively.Then the global network properties (normalized clustering coefficient,normalized shortest path length,small-worldness and global efficiency) and local parameters (clustering coefficient and betweenness centrality of the node) were calculated using the graph theory.Differences between 2 groups were compared by permutation test with 1000 permutations.The top 20％ (18/90) were classified as Hub nodes based on the results of clustering coefficient and betweenness centrality of the node.Results Small-worldness of SFD patients was similar to that of healthy controls (σ＞ 1).There were decreased tendency in normalized clustering coefficient and global efficiency,and increased tendency in normalized shortest path length in SFD patients,but without significant differences (P＞0.05).Compared to healthy controls,the betweenness centrality of left pallidum,left amygdala,left precuneus and right angular gyrus increased (permutation test,P＜0.05);the betweenness centrality of left middle temporal gyrus,right superior occipital gyrus decreased (permutation test,P＜0.05);the clustering coefficients of bilateral pallidum,bilateral thalamus,and left amygdala decreased (permutation test,P ＜ 0.05).Most changed Hub nodes (16/24) belonged to limbic system.Conclusion The changes of topological properties of brain glucose metabolic network in SFD patients including the decreased tendency of small-worldness and global efficiency,as well as the altered Hub nodes,may provide valid imaging evidences for brain dysfunction of somatization symptoms.