Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
China National Clinical Research Center for Neurological Diseases, Beijing, China.
Neural Plast. 2020 Oct 24;2020:8886803. doi: 10.1155/2020/8886803. eCollection 2020.
Focal brain lesions, such as stroke and tumors, can lead to remote structural alterations across the whole-brain networks. Brain arteriovenous malformations (AVMs), usually presumed to be congenital, often result in tissue degeneration and functional displacement of the perifocal areas, but it remains unclear whether AVMs may produce long-range effects upon the whole-brain white matter organization. In this study, we used diffusion tensor imaging and graph theory methods to investigate the alterations of brain structural networks in 14 patients with AVMs in the presumed Broca's area, compared to 27 normal controls. Weighted brain structural networks were constructed based on deterministic tractography. We compared the topological properties and network connectivity between patients and normal controls. Functional magnetic resonance imaging revealed contralateral reorganization of Broca's area in five (35.7%) patients. Compared to normal controls, the patients exhibited preserved small-worldness of brain structural networks. However, AVM patients exhibited significantly decreased global efficiency ( = 0.004) and clustering coefficient ( = 0.014), along with decreased corresponding nodal properties in some remote brain regions ( < 0.05, family-wise error corrected). Furthermore, structural connectivity was reduced in the right perisylvian regions but enhanced in the perifocal areas ( < 0.05). The vulnerability of the left supramarginal gyrus was significantly increased ( = 0.039, corrected), and the bilateral putamina were added as hubs in the AVM patients. These alterations provide evidence for the long-range effects of AVMs on brain white matter networks. Our preliminary findings contribute extra insights into the understanding of brain plasticity and pathological state in patients with AVMs.
脑局灶性病变，如中风和肿瘤，可导致全脑网络的远程结构改变。脑动静脉畸形（AVM）通常被认为是先天性的，常导致病灶周围区域的组织退化和功能移位，但目前尚不清楚 AVM 是否会对全脑白质组织产生远程影响。在这项研究中，我们使用弥散张量成像和图论方法，比较了 14 例假定在布罗卡区的 AVM 患者与 27 名正常对照者的大脑结构网络变化。基于确定性轨迹追踪构建加权脑结构网络。我们比较了患者和正常对照组之间的拓扑性质和网络连接。功能磁共振成像显示 5 名患者（35.7%）存在对侧布罗卡区的重组。与正常对照组相比，患者的脑结构网络具有保留的小世界特性。然而，AVM 患者表现出明显降低的全局效率（ = 0.004）和聚类系数（ = 0.014），以及一些远程脑区的对应节点属性降低（ < 0.05，经家族性错误校正）。此外，右侧大脑外侧裂周围区域的结构连接减少，病灶周围区域的结构连接增强（ < 0.05）。左侧缘上回的脆弱性显著增加（ = 0.039，经校正），双侧壳核被添加为 AVM 患者的枢纽。这些改变为 AVM 对大脑白质网络的远程影响提供了证据。我们的初步发现为理解 AVM 患者的大脑可塑性和病理状态提供了额外的见解。
