Purpose: Childhood absence epilepsy (CAE) is associated with functional changes in specific brain regions and connections. However, little is known about the topological properties of the functional brain connectome in drug naive CAE.
Methods: We adopted the resting-state EEG-fMRI and graph theoretic approach to investigate both local and global brain functional network properties of drug naive CAE during interictal resting state compared with healthy control. In addition, we computed the partial correlation coefficient to estimate the correlation between the functional network metrics and the measured disease duration or the age at seizure onset.
Results: The functional connectome in drug naive CAE showed decreased small-worldness and normalized clustering coefficient at the global level. At the nodal level, decreased nodal centralities were mainly in bilateral prefrontal-thalamocortical circuit and increased nodal centralities mainly in left hippocampus and right middle temporal gyrus (p < 0.05). In addition, the duration of the epilepsy was significantly correlated with the nodal efficiency in left middle frontal gyrus (r = -0.627, p = 0.012).
Conclusion: The pretreatment topological disruptions of whole-brain networks exist in drug naive patients with CAE and the functional impairment mainly involve the prefrontal-thalamocortical circuit. These findings in the homogeneous group of CAE indicate that the aberrant topological organization of functional brain network is an intrinsic feature of CAE and provide topologic insights into understanding the pathophysiological mechanisms of CAE.
Keywords: Childhood absence epilepsy; EEG-fMRI; Graph theory; Small-worldness.
Copyright © 2022. Published by Elsevier B.V.