Increased Intracranial EEG Power and Duration in Medial Temporal Lobe Seizures with Impaired Consciousness
Abstract number :
3.193
Submission category :
4. Clinical Epilepsy / 4A. Classification and Syndromes
Year :
2021
Submission ID :
1825721
Source :
www.aesnet.org
Presentation date :
12/6/2021 12:00:00 PM
Published date :
Nov 22, 2021, 06:50 AM
Authors :
Imran Quraishi, MD, PhD - Yale University School of Medicine; Bogdan Patedakis Litvinov, MD – Yale University; Courtney Yotter, B.S., M.S. – Yale University; Zan Ahmad, B.S. – Yale University; Hal Blumenfeld, MD, PhD – Yale University; Nisali Gunawardane, MD – Yale University; Avisha Kumar, B.S., M.Eng – Yale University
Rationale: Consciousness is essential to normal human life, and its transient loss can have severe effects on quality of life and mortality. In this study, we used intracranial EEG to determine differing characteristics between medial temporal lobe seizures with and without impaired consciousness defined by behavioral responsiveness. Our goal was to obtain mechanistic insights, and to elucidate signal characteristics that could potentially be used to prevent impaired consciousness using neurostimulation.
Methods: Intracranial EEG from 8 patients with a total of 76 medial temporal lobe seizures were analyzed. Behavioral responsiveness was independently rated by two video reviewers and classified broadly into impaired and spared responsiveness to external stimuli. EEG signals from each electrode contact were processed using fast Fourier transform to calculate the signal power at different frequencies. Signals were synchronized to time of seizure onset and averaged across electrodes within major anatomical regions. The change in power from preictal baseline was compared between seizures with impaired and spared behavioral responsiveness.
Results: Group data averages (ictal vs preictal baseline) were analyzed for different frequency bands (delta, theta, alpha, beta, and gamma) for seizures with (n = 18) and without (n = 58) impaired behavioral responsiveness. Mean duration of seizures with impaired behavioral responsiveness (99.18 ± 62.07 s) was significantly longer than for those without impairment (53.72 ± 33.91 s; p< 0.05). In addition, seizures with impaired behavioral responsiveness were trending towards greater EEG signal power in all frequency bands in temporal lobe onset contacts.
Clinical Epilepsy