Functional and Structural Networks Decoupling in GTCS and Its Reorganization by Drugs

Abstract

Objective:The present study aims to investigate the potential disturbance of functional and structural large-scale networks in drug-naive patients with generalized tonic-clonic seizures (GTCS) and the effects of drugs-receiving.Methods:In this study, 41 patients with GTCS, including 21 drug-naive patients and 20 patients with antiepileptic drugs (AEDs), and 29 healthy controls were recruited to construct large-scale brain networks based on the resting-state functional magnetic resonance imaging (fMRI) and diffusion tensor image (DTI). The structural and functional connectivity and the coupling between structure and function were further investigated to identify the network features that responded to drugs.Results:Drug-naive patients showed extensively enhanced functional and structural connections compared with controls. Especially, abnormally enhanced connections between the default mode network (DMN) and the frontal parietal network (FPN) were observed. Besides, drug-receiving patients showed similar functional connection strength to that of the control group. However, drug-receiving and drug-naive patients demonstrated similar alterations in the structural network. Moreover, the structural and functional coupling was decreased in connections within DMN and DMN with other networks, and drug-receiving could reverse the decrease.Significance:These findings identified the pattern alteration of structural and functional connectivity in GTCS patients. AEDs treatment benefit for the seizures might originate from the effects of the functional network rather than the structural network. However, it can improve the abnormal brain network by affecting the coupling relationship. The coupling of structural and functional connectivity might be used to evaluate the efficacy of AEDs.