Klugah-Brown Benjamin, Luo Cheng, Peng Rui, He Hui, Li Jianfu, Dong Li, Yao Dezhong
The Clinical Hospital of Chengdu Brain Science Institute, MOE Key Lab for Neuroinformation, Center for Information in Medicine, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, School of Life Science and Technology, University of Electronic Science and Technology of China, No. 4, Section 2, North Jianshe Road, Chengdu, People's Republic of China.
BMC Neurol. 2019 Apr 25;19(1):70. doi: 10.1186/s12883-019-1300-z.
Albeit the few resting-state fMRI neuroimaging studies in frontal lobe epilepsy (FLE) patients, these studies focused on functional connectivity. The aim of this current study was to examine the effective connectivity based on voxel-based morphometry in FLE patients.
Resting-state structural and functional magnetic resonance imaging (fMRI) data were acquired from 19 FLE patients and 19 age and gender-matched healthy controls using the 3.0 Tesla magnetic resonance imaging (3.0 T MRI). The investigations were done by acquiring the structural information through voxel-based morphometry, then based on the seed obtained, Granger causality analysis was used to evaluate the causal flow of the designated seed to and from other significant voxels.
Our results showed altered structural and effective connectivity. Compared with healthy controls, FLE patients showed reduced grey matter volume in bilateral putamen and right caudate as well as altered causality with increased, and decreased causal outflow from the right caudate (seed region) to inferior frontal gyrus-triangular, from bilateral putamen (seed regions) to right middle frontal gyrus and frontal gyrus medial-orbital representing the frontal executive areas, respectively. Also, significantly increased and decreased inflow from left calcarine to right caudate and from cerebellum_6 and vermis_6 to bilateral putamen, respectively. Moreover, we found that the causal alterations to and from the seed regions (from vermis_6 to right putamen and from left putamen to right middle frontal gyrus) negatively correlated with clinical scores (duration of epilepsy).
The findings point to the impairment within the executive and motor-controlled system including the cerebellum, frontal, caudate and putamen regions in FLE patients. These results would therefore enhance our understanding of structural and effective mechanisms in FLE.
尽管针对额叶癫痫（FLE）患者进行的静息态功能磁共振成像神经影像学研究较少，但这些研究主要聚焦于功能连接。本研究的目的是基于体素形态学分析来检查FLE患者的有效连接。
使用3.0特斯拉磁共振成像（3.0 T MRI），从19例FLE患者以及19名年龄和性别匹配的健康对照者获取静息态结构和功能磁共振成像（fMRI）数据。通过体素形态学分析获取结构信息，然后基于所得种子点，采用格兰杰因果分析来评估指定种子点与其他显著体素之间的因果流向。
我们的结果显示结构和有效连接发生了改变。与健康对照者相比，FLE患者双侧壳核和右侧尾状核的灰质体积减少，并且因果关系发生改变，右侧尾状核（种子区域）至额下回三角区的因果流出增加，双侧壳核（种子区域）至右侧额中回和额眶内侧回（分别代表额叶执行区域）的因果流出减少。此外，左侧距状裂至右侧尾状核以及小脑_6和蚓部_6至双侧壳核的流入分别显著增加和减少。而且，我们发现种子区域的因果改变（从蚓部_6至右侧壳核以及从左侧壳核至右侧额中回）与临床评分（癫痫持续时间）呈负相关。
研究结果表明FLE患者的执行和运动控制系统（包括小脑、额叶、尾状核和壳核区域）存在损伤。因此，这些结果将增进我们对FLE结构和有效机制的理解。
