Authors :
Presenting Author: Feng Gao, MD – Zhejiang University
Feng Gao, MD – Zhejiang University
Runze zhen, PHD – Hangzhou Dianzi University
lu xu, MD – Zhejiang University
jue shen, MD – Zhejiang University
jiuwen cao, PHD – Hangzhou Dianzi University
Rationale:
Infantile epileptic spasms syndrome (IESS) represents one of the prototypical developmental epileptic encephalopathies. Epileptic spasms pose a risk of inducing irreversible disruptions in brain function by disturbing neural homeostasis—a critical determinant of cognitive and motor function. Given this, elucidating the spatiotemporal dynamics of brain functional networks (BFNs) during seizure events is therefore critical for understanding how such networks impair global brain functional states and associated cognitive processes.
Methods:
We put forward a dynamic network analysis framework that integrates EEG microstate analysis and source localization to quantify the changes in BFNs throughout infantile spasms and appraise their functional impact. Specifically: (1) Using K-means clustering, we identified four dominant microstate patterns (A–D) across five seizure phases: interictal, preictal, the Seizure Prediction Horizon (SPH), ictal, and postictal. Paired t-tests were employed to compare the dynamic microstate parameter changes between these phases, aiming to evaluate the effect of seizures on the global topological stability. (2) For each frequency band, we constructed microstate - specific signals per phase, mapped these signals to the cortex via source localization, and then utilized multifactorial ANOVA (Analysis of Variance) to assess the changes in the distribution of cortical current density. (3) After parcellating the cortex into eight functional networks, we calculated the mean current density per band per network and applied multifactorial ANOVA to identify the phase-specific impairments.Results:
Analysis of EEG data from 25 infants demonstrated that epileptic spasms significantly perturbed BFN homeostasis, particularly within core cognitive/motor networks (visual, default mode, attention, and sensorimotor networks), thereby impeding the typical progression of cerebral lateralization. Notably, alterations in power spectral density (PSD) within the alpha, beta, and gamma bands were identified as robust biomarkers of seizure-induced functional impairment.
Conclusions:
These findings yield novel mechanistic insights into how infantile spasms disrupt brain function. The identified biomarkers provide critical guidance for optimizing clinical interventions aimed at mitigating cognitive and motor deficits in affected infants.
Funding: There is no funding to support the project