Discovery of recurrent multiple brain states in non-convulsive status epilepticus

Objective: We study burst-like patterns of epileptiform discharges in non-convulsive status epilepticus (SE). Methods: Epileptiform burst-like transients were identified by estimating the amplitude envelope of the EEG signal, and recurrence and similarities were identified by pairwise matching in the time-domain. Results: We identified similarities in the onset of a significant fraction of the epileptiform bursts, and a bimodal distribution of the burst durations. Conclusions: Bursts of epileptiform discharges during a non-convulsive SE are manifestations of multiple patterns of recurring brain states. Significance: Quantitative description of ictal phenomena in epilepsy and status epilepticus adds to the knowledge of abnormal brain behavior and may assist in improved patient care. (c) 2007 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.