Under-sampling in epilepsy: Limitations of conventional EEG

The cyclical structure of epilepsy was recently (re)-discovered through years-long intracranial electroencephalography (EEG) obtained with implanted devices. In this review, we discuss how new revelations from chronic EEG relate to the practice and interpretation of conventional EEG. We argue for an electrographic definition of seizures and highlight the caveats of counting epileptiform discharges in EEG recordings of short duration. Limitations of conventional EEG have practical implications with regard to titrating anti-seizure medications and allowing patients to drive, and we propose that chronic monitoring of brain activity could greatly improve epilepsy care. An impending paradigm shift in epilepsy will involve using next-generation devices for chronic EEG to leverage known biomarkers of disease state. (C) 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V.

Automated summary

The cyclical structure of epilepsy has been recently rediscovered through long-term intracranial electroencephalography obtained with implanted devices, providing new insights into the practice and interpretation of conventional EEG. There are caveats to counting epileptiform discharges in short-duration EEG recordings and the limitations of conventional EEG have practical implications for titrating anti-seizure medications and allowing patients to drive. Chronic monitoring of brain activity could greatly improve epilepsy care, and utilizing next-generation devices for chronic EEG could leverage known biomarkers of disease state in an impending paradigm shift in epilepsy care.