Diagnostic Yield of Electroencephalography When Seizure Is Suspected in Acute Ischemic Stroke

Seizures are a common complication after an ischemic stroke. Electroencephalography can assist with the diagnosis of seizures however, the diagnostic yield of its use when seizure is suspected in the setting of acute ischemic stroke is unknown. We aim to evaluate the yield and cost of EEG in the acute ischemic stroke setting.

We conducted a retrospective chart review of patients admitted to a single academic tertiary care center in the United States between September 1, 2015 to November 30, 2019 with a primary diagnosis of acute ischemic stroke and who were monitored on electroencephalography (EEG) for suspected seizures (total number of 70 patients). The primary outcome was how often EEG monitoring changed clinical management defined as starting, stopping, or changing the dose of an anti-epileptic drug. Secondary analysis was estimating the cost of EEG monitoring per change in management.

We identified 126 patients admitted with acute ischemic stroke who underwent EEG of which 70 met all inclusion and exclusion criteria. EEG monitoring resulted in a change in management in 22 patients (31%). Predictors associated with EEG monitoring resulting in a change in management were admission to the ICU, pre-existing atrial fibrillation, and symptomatic hemorrhagic transformation. Estimated cost of EEG per change in management was $1374.96 USD.

EEG monitoring resulted in a changed management in nearly one-third of patients admitted with acute ischemic stroke suspected of having seizures.