Department of Neurology, Manchester Centre for Clinical Neurosciences, Salford, UK.
Division of Neuroscience and Experimental Psychology, Faculty of Biology, Medicine, and Health, School of Biological Sciences, University of Manchester, Manchester, UK.
Epilepsia. 2021 Feb;62(2):492-503. doi: 10.1111/epi.16811. Epub 2021 Jan 26.
The study aim was to compare interictal encephalographic (EEG) functional network topology between people with well-controlled idiopathic generalized epilepsy (WC-IGE) and drug-resistant IGE (DR-IGE).
Nineteen participants with WC-IGE, 18 with DR-IGE, and 20 controls underwent a resting state, 64-channel EEG. An artifact-free epoch was bandpass filtered into the frequency range of high and low extended alpha. Weighted functional connectivity matrices were calculated. Mean degree, degree distribution variance, characteristic path length (L), clustering coefficient, small world index (SWI), and betweenness centrality were measured. A Kruskal-Wallis H-test assessed effects across groups. Where significant differences were found, Bonferroni-corrected Mann-Whitney pairwise comparisons were calculated.
In the low alpha band (6-9 Hz), there was a significant difference in L at the three-group level (p < .0001). This was lower in controls than both WC-IGE and DR-IGE (p < .0001 for both), with no difference in L between WC-IGE and DR-IGE. Mean degree (p = .031), degree distribution variance (p = .032), and SWI (p = .023) differed across the three groups in the high alpha band (10-12 Hz). Mean degree and degree distribution variance were lower in WC-IGE than controls (p = .029 for both), and SWI was higher in WC-IGE compared with controls (p = .038), with no differences in other pairwise comparisons.
IGE network topology is more regular in the low alpha frequency band, potentially reflecting a more vulnerable structure. WC-IGE network topology is different from controls in the high alpha band. This may reflect drug-induced network changes that have stabilized the WC-IGE network by rendering it less likely to synchronize. These results are of potential importance in advancing the understanding of mechanisms of epilepsy drug resistance and as a possible basis for a biomarker of DR-IGE.
本研究旨在比较控制良好的特发性全面性癫痫（WC-IGE）和耐药性 IGE（DR-IGE）患者的发作间期脑电图（EEG）功能网络拓扑结构。
19 名 WC-IGE 患者、18 名 DR-IGE 患者和 20 名对照者接受了静息状态下的 64 通道 EEG 检查。去除伪迹后，将无伪迹的时段带通滤波到高扩展阿尔法和低扩展阿尔法频段。计算加权功能连接矩阵。测量平均节点度、节点度分布方差、特征路径长度（L）、聚类系数、小世界指数（SWI）和介数中心性。Kruskal-Wallis H 检验评估组间效应。发现显著差异时，采用 Bonferroni 校正的 Mann-Whitney 两两比较进行计算。
在低阿尔法频段（6-9 Hz），三组间 L 存在显著差异（p <.0001）。与 WC-IGE 和 DR-IGE 相比，对照组的 L 均显著降低（p <.0001，两者均如此），而 WC-IGE 和 DR-IGE 之间的 L 无差异。在高阿尔法频段（10-12 Hz），三组间的平均节点度（p =.031）、节点度分布方差（p =.032）和小世界指数（SWI）（p =.023）均存在差异。与对照组相比，WC-IGE 的平均节点度和节点度分布方差均较低（p =.029，两者均如此），而 SWI 则较高（p =.038），其他两两比较无差异。
IGE 网络拓扑结构在低阿尔法频段更为规则，这可能反映出结构更为脆弱。WC-IGE 的网络拓扑结构与对照组在高阿尔法频段不同。这可能反映了药物引起的网络变化，通过降低 WC-IGE 网络的同步可能性，使其更稳定。这些结果对于深入了解癫痫耐药的机制以及作为 DR-IGE 的生物标志物具有潜在的重要性。
