Department of Neurology, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea.
Department of Health Science and Technology, Inje University, Gimhae, Korea.
Acta Neurol Scand. 2018 Apr;137(4):425-431. doi: 10.1111/ane.12899. Epub 2018 Jan 17.
Increasing evidence has suggested that epilepsy is a network disease. Graph theory is a mathematical tool that allows for the analysis and quantification of the brain network. We aimed to evaluate the influences of duration of epilepsy on the topological organization of brain network in focal epilepsy patients with normal MRI using the graph theoretical analysis based on diffusion tenor imaging.
We prospectively enrolled 66 patients with focal epilepsy (18/66 patients were newly diagnosed) and 84 healthy subjects. All of the patients with epilepsy had normal MRI on visual inspection. All of the subjects underwent diffusion tensor imaging that was analyzed using graph theory to obtain network measures.
The measures of characteristic path length and small-worldness in the patients with focal epilepsy were significantly decreased, even after multiple corrections (P < .01). Moreover, the measures including mean clustering coefficient and global efficiency in the patients with epilepsy had strong tendency to decrease compared to those in healthy subjects (P = .0153 and P = .0138, respectively). When comparing the measures among the patients with newly diagnosed/chronic epilepsy and healthy subjects using ANOVA, the characteristic path length (P = .006), small-worldness (P = .032), and global efficiency (P = .004) were significantly different. In addition, the duration of epilepsy was negatively correlated with global efficiency (r = -.249, P = .0454).
We newly found a progressive topological disorganization of the brain network in focal epilepsy. In addition, we demonstrated disrupted topological organization in focal epilepsy, shifting toward a more random state.
越来越多的证据表明癫痫是一种网络疾病。图论是一种数学工具，可用于分析和量化大脑网络。我们旨在使用基于弥散张量成像的图论分析，评估癫痫持续时间对正常 MRI 的局灶性癫痫患者脑网络拓扑组织的影响。
我们前瞻性地招募了 66 名局灶性癫痫患者（18/66 名患者为新诊断）和 84 名健康受试者。所有癫痫患者的 MRI 均通过视觉检查正常。所有受试者均接受弥散张量成像，使用图论进行分析以获得网络指标。
局灶性癫痫患者的特征路径长度和小世界性的指标明显降低，即使经过多次校正（P<.01）。此外，与健康受试者相比，癫痫患者的平均聚类系数和全局效率等指标有强烈下降的趋势（P=.0153 和 P=.0138）。使用方差分析比较新诊断/慢性癫痫患者与健康受试者的各项指标，特征路径长度（P=.006）、小世界性（P=.032）和全局效率（P=.004）有显著差异。此外，癫痫持续时间与全局效率呈负相关（r=-.249，P=.0454）。
我们新发现局灶性癫痫患者脑网络存在进行性拓扑结构紊乱。此外，我们证明局灶性癫痫存在拓扑组织紊乱，向更随机的状态转变。
