Correlation between EEG spectral power and cerebral perfusion in patients with acute ischemic stroke

•Dry electrode EEG has the potential to diagnose ischemic stroke in the acute phase.•Slower dry electrode EEG activity correlates with larger hypoperfused volume.•Dry electrode EEG slowing is not limited to the hypoperfused area. Dry electrode electroencephalography (EEG) has the potential to diagnose ischemic stroke in the acute phase. In the current study we determined the correlation between EEG spectral power and ischemic stroke size and location as determined by computed tomography perfusion (CTP). Dry electrode EEG recordings were performed in patients with acute ischemic stroke in the emergency room. CTP preceded the EEG recordings as part of standard imaging protocol. Infarct core volume, total hypoperfused volume and local cerebral blood flow (CBF) were estimated with CTP. Additionally, global and local EEG spectral power were determined. We used Spearman’s correlation coefficients to evaluate the correlation between variables. We included 27 patients (median age 72 [IQR:69–80] years, 15/27 [56%] men). Median CTP-to-EEG time was 32 (range:8–138) minutes. Hypoperfused volumes were estimated for 12/27 (44%) patients. Infarct core volume correlated best with global delta power (ρ = 0.76, p