Epilepsia open
Stability of the Epileptogenic Index across seizures and the effects of sleep and withdrawal of anti-seizure medications
By Bar-On M, Ben-Eliezer N, Fallik N and 5 others.
Abstract
Objective
Epileptogenic Index (EI) is a promising index to evaluate the epileptogenicity of the brain tissue and is useful in planning epilepsy surgery. We aimed to evaluate whether EI maps are consistent across seizures within patients and whether EI-derived measures are affected by the vigilance state and anti-seizure medication (ASM) dose.
Methods
We analyzed 127 stereoelectroencephalography (SEEG) seizures from 19 patients. EI was calculated in all seizures. Within-patient EI consistency was assessed using pairwise Spearman correlations between seizure-specific EI maps. To assess the effects of vigilance and ASM on EI consistency, we calculated a contact-level p_weighted EI score that combines the frequency of suprathreshold EI involvement and mean EI magnitude, separately across vigilance states and in a subset of patients with different ASM states.