Purpose: The cerebral glymphatic system, particularly the Virchow-Robin Spaces (VRS), plays an important role in waste clearance from the brain. Idiopathic generalized epilepsy (IGE) is a common epilepsy type associated with blood-brain-barrier dysfunction, abnormal exchange of cerebrospinal fluid and interstitial fluid. These disorders may be reflected in the glymphatic system. Therefore, this study investigated the relationships between visible VRS on MRI and seizures, to detect changes in glymphatic function.
Methods: We retrospectively included 32 children with newly diagnosed IGE and 30 controls aged 3-13 years. Visible VRS were identified using a custom-designed automated method. VRS counts and volume were quantified and compared between children with IGE and controls. Meanwhile, Correlations of VRS counts and volume with seizure duration and course after seizure onset were respectively explored via Spearman's coefficient (r).
Results: In this study, visible VRS counts were higher in IGE than control group (VRS_epilepsy, 234.34 ± 113.88 vs. VRS_control, 111.83 ± 52.46; P < 0.001), as similar results were found in VRS volume (VRS_epilepsy, 1377.47 ± 778.79 mm3 vs. VRS_control, 795.153 ± 452.49 mm3; P = 0.001). Visible VRS counts and volume positively correlated with seizure duration (r_counts = 0.638, r_volume = 0.639; P < 0.001) and gradually decreased with time after seizure onset (r_counts = -0.559, r_volume = -0.558; P < 0.001).
Conclusion: Epileptic seizures can induce changes in VRS counts and volume, which were associated with seizure duration and post-onset course. Quantitative metrics of VRS visible on MRI might be potential biomarkers for monitoring glymphatic function.
Keywords: Child; Glymphatic system; Idiopathic generalized epilepsy; Magnetic resonance imaging; Virchow-Robin spaces.
Copyright © 2020 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.