Zmniejszenie synchronizacji w paśmie beta w spoczynkowych sieciach EEG jako wskaźnik odpowiedzi na okskarbazepin w ogniskowej epilepsji: badanie długookresowe

OBJECTIVES: Using wPLI-based phase synchronization, this study examined changes in EEG functional connectivity in patients with focal epilepsy before and after oxcarbazepine (OXC) monotherapy, with an emphasis on beta-band networks and treatment response. METHODS: Twenty-seven ASM-naive patients with focal epilepsy underwent resting-state 19-channel scalp EEG before OXC monotherapy and again after treatment, with 7-41 months between the two EEG recordings. Patients were classified by one-year clinical outcome as seizure-free (SF; n = 12) or non-seizure-free (NSF; n = 15). wPLI connectivity matrices were computed for δ-γ bands, and network-based statistics (NBS) was used for within-group and between-group comparisons. The exploratory post hoc strength of the NBS-identified beta subnetwork was summarized, and ANCOVA was performed controlling for baseline connectivity. RESULTS: NBS did not reveal significant global pre-post connectivity changes within either group (FWE-corrected p > 0.05). Post-treatment, SF patients showed significantly lower beta-band wPLI than NSF patients on edges F3-P8 and P4-P8 (NBS, p < 0.001). Beta subnetwork strength decreased after treatment in SF patients (p = 0.003) but not in NSF patients, and the reduction was larger in SF patients (p = 0.031). Baseline-adjusted ANCOVA confirmed a significant group effect (p < 0.001). CONCLUSIONS: Seizure-free patients receiving OXC exhibited selective beta-band desynchronization in long-range connections centered on P8. Beta-band subnetwork strength may serve as an exploratory EEG network marker for evaluating OXC treatment response in focal epilepsy.