Continuous Versus Short EEG After Ischemic Stroke: What cEEG Adds for Detecting Abnormalities and Predicting...

Area of Science:

• Neurology
• Clinical Neurophysiology

Background:

• Post-stroke epilepsy (PSE) is a common complication.
• Accurate prediction of PSE is crucial for patient management.
• Current EEG methods may not fully capture epileptiform activity.

Purpose of the Study:

• To compare the diagnostic yield and prognostic value of continuous electroencephalography (cEEG) versus short electroencephalography (sEEG) in predicting PSE.
• To evaluate the incremental value of extended EEG monitoring.

Main Methods:

• Retrospective analysis of 283 adult patients undergoing cEEG within 7 days of stroke.
• sEEG comprised the first 60 minutes of cEEG.
• EEG interpretation by blinded neurophysiologists using ACNS terminology.
• Statistical analysis included odds ratios, competing-risks regression, C-index, and net reclassification improvement (NRI).

Main Results:

• cEEG detected significantly more interictal epileptiform discharges (11% vs 3%) and electrographic seizures (4% vs 0.7%) compared to sEEG.
• Lateralized periodic discharges and electrographic seizures were strong PSE predictors.
• cEEG-derived SeLECT-EEG improved discrimination and reclassification of PSE risk.
• New epileptiform activity after the first hour increased 5-year PSE risk.

Conclusions:

• Continuous electroencephalography (cEEG) provides superior diagnostic and prognostic information for post-stroke epilepsy (PSE) prediction compared to short electroencephalography (sEEG).
• Extended EEG monitoring is valuable for identifying additional epileptiform abnormalities and refining PSE risk assessment.
• Extension of monitoring should be considered in selected cases based on baseline risk and initial EEG findings.