Shih Yao-Chia, Lin Fa-Hsuan, Liou Horng-Huei, Tseng Wen-Yih Isaac
Institute of Biomedical Engineering, National Taiwan University, Taipei, Taiwan.
Institute of Medical Device and Imaging, College of Medicine, National Taiwan University, Taipei, Taiwan.
Brain Connect. 2021 Aug;11(6):457-470. doi: 10.1089/brain.2020.0835. Epub 2021 Apr 5.
Temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) is a common intractable epilepsy. To seek neural correlates of seizure recurrence, this study investigated aberrant intrinsic effective connectivity (iEC) in TLE with unilateral MTS and their associations with seizure frequency. Thirty patients with unilateral MTS (left/right MTS = 14/16) and 37 age-matched healthy controls underwent resting-state functional magnetic resonance imaging (rsfMRI) on a 3-Tesla magnetic resonance imaging (MRI) system. The structural equation modeling was employed to estimate the iEC of the three candidate epilepsy models, including the Papez circuit, hippocampal-diencephalic-cingulate (HDC) model, and simplified HDC model. After comparing the performance of model fitting, the best model was selected to compare iEC among the study groups. The linear regression analysis was performed to associate abnormal iEC with seizure frequency. The simplified HDC model was the best model to estimate iEC across the three study groups ( < 0.05), and it composed of the 26 interconnected pathway between the mesial temporal lobe, thalamus, and cingulate cortices. The linear regression analysis revealed a significant relationship between the shared iEC alterations in both patient groups and seizure frequency (adjusted- = 0.350; = 0.037), including the three paths of mammillary body (MB) → bilateral anterior thalamic nuclei (left: standardized -value = 0.580, = 0.013; right: standardized -value = -0.711, = 0.006) and right hippocampus → MB (standardized -value = 0.541, = 0.045). Our findings provide new insights into neurophysiological significance relevant to seizure recurrence. Aberrant iEC on the neural paths connected to the MB can be a potential imaging marker, aiding the therapeutic management in TLE with unilateral MTS. Impact statement Within the simplified hippocampal-diencephalic-cingulate model, we identified that altered intrinsic effective connectivity (iEC) on the three paths connecting to the mammillary body was common in temporal lobe epilepsy (TLE) with left and right mesial temporal sclerosis (MTS) and was associated with seizure frequency. Therefore, these common iEC alterations could be a potential imaging marker, aiding the therapeutic management in patients with TLE with unilateral MTS.
伴有内侧颞叶硬化（MTS）的颞叶癫痫（TLE）是一种常见的难治性癫痫。为了探寻癫痫复发的神经关联，本研究调查了单侧MTS的TLE患者中异常的内在有效连接性（iEC）及其与癫痫发作频率的关联。30例单侧MTS患者（左侧/右侧MTS = 14/16）和37名年龄匹配的健康对照在3特斯拉磁共振成像（MRI）系统上接受静息态功能磁共振成像（rsfMRI）检查。采用结构方程模型来估计三种候选癫痫模型的iEC，包括帕佩兹环路、海马 - 间脑 - 扣带回（HDC）模型和简化的HDC模型。在比较模型拟合性能后，选择最佳模型来比较各研究组之间的iEC。进行线性回归分析以将异常的iEC与癫痫发作频率相关联。简化的HDC模型是估计三个研究组iEC的最佳模型（<0.05），它由内侧颞叶、丘脑和扣带回皮质之间的26条相互连接的通路组成。线性回归分析显示，两个患者组中共同的iEC改变与癫痫发作频率之间存在显著关系（调整后 = 0.350； = 0.037），包括乳头体（MB）→双侧丘脑前核的三条通路（左侧：标准化 - 值 = 0.580， = 0.013；右侧：标准化 - 值 = -0.711， = 0.006）以及右侧海马→MB（标准化 - 值 = 0.541， = 0.045）。我们的研究结果为与癫痫复发相关的神经生理意义提供了新的见解。与MB相连的神经通路上的异常iEC可能是一种潜在的影像学标志物，有助于单侧MTS的TLE的治疗管理。影响声明 在简化的海马 - 间脑 - 扣带回模型中，我们发现连接到乳头体的三条通路上的内在有效连接性（iEC）改变在伴有左右内侧颞叶硬化（MTS）的颞叶癫痫（TLE）中很常见，并且与癫痫发作频率相关。因此，这些常见的iEC改变可能是一种潜在的影像学标志物，有助于单侧MTS的TLE患者的治疗管理。
