From the Huaxi MR Research Center, Department of Radiology (X.S., D.L., M.W., Lei Li, L.S., X.W., Q.G.), and Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy (H.Z.), West China Hospital of Sichuan University, #37 Guo Xue Xiang, Chengdu, Sichuan 610041, China; Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom (D.L.); Department of Medical Information Engineering, School of Electrical Engineering and Information (F.C.), and Department of Psychology, School of Public Administration (Q.G.), Sichuan University, Chengdu, Sichuan, China; Mental Health Institute, the Second Xiangya Hospital of Central South University, Changsha, Hunan, China (Lingjiang Li); and Department of Musculoskeletal Biology and MRC-Arthritis Research UK Centre for Integrated Research into Musculoskeletal Ageing, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, England (G.J.K.).
Radiology. 2017 Mar;282(3):826-834. doi: 10.1148/radiol.2016160907. Epub 2016 Oct 25.
Purpose To use diffusion-tensor (DT) imaging and graph theory approaches to explore the brain structural connectome in pediatric posttraumatic stress disorder (PTSD). Materials and Methods This study was approved by the relevant research ethics committee, and all participants' parents or guardians provided informed consent. Twenty-four pediatric patients with PTSD and 23 control subjects exposed to trauma but without PTSD were recruited after the 2008 Sichuan earthquake. The structural connectome was constructed by using DT imaging tractography and thresholding the mean fractional anisotropy of 90 brain regions to yield 90 × 90 partial correlation matrixes. Graph theory analysis was used to examine the group-specific topologic properties, and nonparametric permutation tests were used for group comparisons of topologic metrics. Results Both groups exhibited small-world topology. However, patients with PTSD showed an increase in the characteristic path length (P = .0248) and decreases in local efficiency (P = .0498) and global efficiency (P = .0274). Furthermore, patients with PTSD showed reduced nodal centralities, mainly in the default mode, salience, central executive, and visual regions (P < .05, corrected for false-discovery rate). The Clinician-Administered PTSD Scale score was negatively correlated with the nodal efficiency of the left superior parietal gyrus (r = -0.446, P = .043). Conclusion The structural connectome showed a shift toward "regularization," providing a structural basis for functional alterations of pediatric PTSD. These abnormalities suggest that PTSD can be understood by examining the dysfunction of large-scale spatially distributed neural networks. RSNA, 2016.
目的 利用弥散张量（DT）成像和图论方法探索儿童创伤后应激障碍（PTSD）的脑结构连接组。
材料与方法 本研究经相关研究伦理委员会批准，所有参与者的父母或监护人均提供了知情同意书。在 2008 年四川地震后，招募了 24 名患有 PTSD 的儿科患者和 23 名暴露于创伤但无 PTSD 的对照受试者。通过 DT 成像追踪法构建结构连接组，并对 90 个脑区的平均分数各向异性进行阈值处理，得出 90×90 部分相关矩阵。利用图论分析来检测组间特定的拓扑特性，并对拓扑指标进行组间非参数置换检验。
结果 两组均表现出小世界拓扑结构。然而，PTSD 患者的特征路径长度增加（P=0.0248），局部效率（P=0.0498）和全局效率（P=0.0274）降低。此外，PTSD 患者的节点中心度降低，主要集中在默认模式、突显、中央执行和视觉区域（P＜0.05，经假发现率校正）。临床医生管理的 PTSD 量表评分与左侧顶上回的节点效率呈负相关（r=-0.446，P=0.043）。
结论 结构连接组显示出向“规则化”的转变，为儿童 PTSD 的功能改变提供了结构基础。这些异常表明，通过检查大规模空间分布神经网络的功能障碍，可以理解 PTSD。
放射学学会，2016 年。
