Brain glucose metabolism network and connectivity in patients with somatoform disorders / 中华核医学与分子影像杂志

ABSTRACT

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.