Static and dynamic functional connectivity of unruptured arteriovenous malformations-related epilepsy: A...

To investigate the static and dynamic network alteration during the interictal phase in patients with epileptic unruptured arteriovenous malformation (AVM).

This study employed the seed-to-seed functional connectivity (FC) and the Hidden Markov Model (HMM) to analyze resting-state functional MRI (rsfMRI) data from 24 AVM patients at a single neurosurgery center and 23 control subjects from public datasets. The HMM successfully identified brain states related to AVM subgroups, which were further evaluated using intra- and inter-network-level FC analysis and graph theory.

Compared to the healthy controls, significant enhancement of static FC between the bilateral superior occipital gyrus and left inferior parietal lobule-angular gyrus was found in epileptic AVMs. Meanwhile, in the dynamic FC analyses, we identified distinct brain states linked to epileptic and asymptomatic AVMs, marked by characteristic FC alteration at the intra- and inter-network level. Notably, significantly decreased integration and increased intra-network connection of the visual network were observed in states related to epileptic AVMs.

Epileptic AVMs have unique dynamic network interactions during interictal phase. These patients exhibited a propensity for rapid transitions and frequent visits to a functionally less efficient state, marked by significantly decreased integration of visual network. This study contributes to our understanding of AVM-related epilepsy pathophysiology and may help to further identify potential diagnostic or treatment targets.