Bonilha Leonardo, Tabesh Ali, Dabbs Kevin, Hsu David A, Stafstrom Carl E, Hermann Bruce P, Lin Jack J
Department of Neurosciences, Division of Neurology, Medical University of South Carolina, Charleston, South Carolina.
Hum Brain Mapp. 2014 Aug;35(8):3661-72. doi: 10.1002/hbm.22428. Epub 2014 Jan 22.
Recent neuroimaging and behavioral studies have revealed that children with new onset epilepsy already exhibit brain structural abnormalities and cognitive impairment. How the organization of large-scale brain structural networks is altered near the time of seizure onset and whether network changes are related to cognitive performances remain unclear. Recent studies also suggest that regional brain volume covariance reflects synchronized brain developmental changes. Here, we test the hypothesis that epilepsy during early-life is associated with abnormalities in brain network organization and cognition. We used graph theory to study structural brain networks based on regional volume covariance in 39 children with new-onset seizures and 28 healthy controls. Children with new-onset epilepsy showed a suboptimal topological structural organization with enhanced network segregation and reduced global integration compared with controls. At the regional level, structural reorganization was evident with redistributed nodes from the posterior to more anterior head regions. The epileptic brain network was more vulnerable to targeted but not random attacks. Finally, a subgroup of children with epilepsy, namely those with lower IQ and poorer executive function, had a reduced balance between network segregation and integration. Taken together, the findings suggest that the neurodevelopmental impact of new onset childhood epilepsies alters large-scale brain networks, resulting in greater vulnerability to network failure and cognitive impairment.
近期的神经影像学和行为学研究表明,新发癫痫患儿已表现出脑结构异常和认知障碍。癫痫发作开始时附近大规模脑结构网络的组织如何改变,以及网络变化是否与认知表现相关仍不清楚。近期研究还表明,区域脑体积协方差反映了同步的脑发育变化。在此,我们检验这样一个假设:早期癫痫与脑网络组织和认知异常有关。我们使用图论,基于39名新发癫痫患儿和28名健康对照的区域体积协方差来研究脑结构网络。与对照组相比,新发癫痫患儿表现出拓扑结构组织欠佳,网络分离增强而全局整合减弱。在区域水平上,结构重组明显,节点从后头部区域重新分布到更靠前的头部区域。癫痫脑网络更容易受到有针对性而非随机攻击的影响。最后,癫痫患儿的一个亚组,即智商较低和执行功能较差的患儿,在网络分离和整合之间的平衡降低。综上所述,研究结果表明,新发儿童癫痫的神经发育影响会改变大规模脑网络,导致对网络故障和认知障碍的易感性增加。