基于DTI的视神经脊髓炎谱系疾病患者脑结构网络的拓扑属性改变研究

Changes in topological properties of brain structural network in patients with neuromyelitis optica spectrum disorder based on diffusion tensor imaging

目的 探讨视神经脊髓炎谱系疾病（NMOSD）患者脑结构网络的拓扑属性特点. 方法 对中山大学附属第三医院神经内科自2014年9月至2017年10月收治的41例NMOSD患者（患者组）及40例年龄、性别相匹配的健康志愿者（对照组）进行弥散张量成像（DTI）扫描,采用确定性纤维跟踪技术构建脑白质结构加权网络,进而计算基于复杂图论分析的脑结构网络拓扑属性,使用非参数置换检验对2组脑结构网络的总体参数及节点属性参数进行对比分析. 结果 2组受试者的脑结构网络均具有小世界属性.患者组脑结构网络较对照组全局效率明显减小,最短路径长度明显增加,差异均有统计学意义（P=0.002,P=0.002,FDR校正）;患者组与对照组脑结构网络的聚类系数、平均最短路径长度、小世界属性值、平均聚类系数、局部效率差异均无统计学意义（P=0.780,P=0.496,P=0.279,P=0.269,P=0.050,FDR校正）.与对照组比较,患者组脑结构网络节点效率在额叶（双侧中央前回、右眶部额中回、右岛盖部额下回、右中央沟盖、双侧内侧和旁扣带回）、顶叶（右后扣带回、右顶上回、左顶下缘角回、右角回、右楔前叶）、颞叶（双侧海马、右海马旁回）、枕叶（左楔叶、左枕上回、双侧枕中回、左枕下回）及皮质下区域（右尾状核、右丘脑）明显降低,差异均有统计学意义（P＜0.05,FDR校正）. 结论 NMOSD患者脑结构网络存在连接异常.

Objective To explore the topological properties of the brain structural network in patients with neuromyelitis optica spectrum disorder （NMOSD）.Methods Diffusion tensor imaging was performed in 41 NMOSD patients （patient group） and 40 age-and sex-matched healthy volunteers （control group） who were admitted to the Department of Neurology,The Third Affiliated Hospital to Sun Yat-sen University from September 2014 to October 2017.The deterministic fiber tracking techniques were used to construct the white matter structural weighted network.Topological properties of the brain structural network were then calculated based on complex graph theory analysis.The 2 groups were compared in terms of global and local parameters of the brain structural network using statistical methods.Results The brain structural networks in both groups exhibited small world properties.Compared with the control group,the global efficiency of the brain structural network in the patient group was significantly decreased and the shortest path length significantly increased （P=0.002,P=0.002,FDR correction）.There were no statistically significant differences between the brain structural networks of the 2 groups in terms of clustering coefficient,the shortest path length on average,value of small world property,average clustering coefficient or local efficiency （P=0.780,P=0.496,P=0.279,P=0.269,P=0.050,FDR correction）.Compared with the control group,the nodal efficiency of the brain structural network of the patient group was significantly decreased in the frontal lobe （bilateral precentral gyrus,middle frontal gyrus of the right orbital part,inferior frontal gyrus of the right opercular part,right rolandic operculum,bilateral median cingulate and paracingulate gyri）,parietal lobe （right posterior cingulate gyrus,right superior parietal gyrus,left inferior parietal of angular gyri,right angle gyrus,and right precuneus）,temporal lobe （bilateral hippocampus and right parahippocampal gyrus）,occipital lobe （left cuneus,left superior occipital gyms,bilateral middle occipital gyrus,and left inferior occipital gyrus） and subcortical region （right caudate nucleus and right thalamus） （P＜0.05,FDR correction）.Conclusion There is abnormal connection in brain structural network in NMOSD patients.