Nakuci Johan, McGuire Matthew, Schweser Ferdinand, Poulsen David, Muldoon Sarah F
Neuroscience Program, University at Buffalo, SUNY, Buffalo, New York, USA.
Department of Neurosurgery, University at Buffalo, SUNY, Buffalo, New York, USA.
Brain Connect. 2022 Nov;12(9):799-811. doi: 10.1089/brain.2021.0168. Epub 2022 May 5.
Traumatic brain injury (TBI) damages white matter tracts, disrupting brain network structure and communication. There exists a wide heterogeneity in the pattern of structural damage associated with injury, as well as a large heterogeneity in behavioral outcomes. However, little is known about the relationship between changes in network connectivity and clinical outcomes. We utilize the rat lateral fluid-percussion injury model of severe TBI to study differences in brain connectivity in 8 animals that received the insult and 11 animals that received only a craniectomy. Diffusion tensor imaging is performed 5 weeks after the injury and network theory is used to investigate changes in white matter connectivity. We find that (1) global network measures are not able to distinguish between healthy and injured animals; (2) injury induced alterations predominantly exist in a subset of connections (subnetworks) distributed throughout the brain; and (3) injured animals can be divided into subgroups based on changes in network motifs-measures of local structural connectivity. In addition, alterations in predicted functional connectivity indicate that the subgroups have different propensities to synchronize brain activity, which could relate to the heterogeneity of clinical outcomes. These results suggest that network measures can be used to quantify progressive changes in brain connectivity due to injury and differentiate among subpopulations with similar injuries, but different pathological trajectories.
创伤性脑损伤（TBI）会损害白质束，破坏脑网络结构和通信。与损伤相关的结构损伤模式存在广泛的异质性，行为结果也存在很大的异质性。然而，关于网络连通性变化与临床结果之间的关系却知之甚少。我们利用大鼠重度TBI的侧方流体冲击损伤模型，研究了8只遭受损伤的动物和11只仅接受颅骨切除术的动物在脑连通性方面的差异。在损伤后5周进行扩散张量成像，并使用网络理论研究白质连通性的变化。我们发现：（1）全局网络测量无法区分健康动物和受伤动物；（2）损伤引起的改变主要存在于分布在整个大脑中的一部分连接（子网）中；（3）受伤动物可以根据网络基序（局部结构连通性的测量）的变化分为亚组。此外，预测功能连通性的改变表明，这些亚组具有不同的同步脑活动倾向，这可能与临床结果的异质性有关。这些结果表明，网络测量可用于量化因损伤导致的脑连通性的渐进变化，并区分具有相似损伤但病理轨迹不同的亚群。
