- Ischemic stroke with a brain lesion visualized by neuroimaging (either brain Computed Tomography (CT) or Magnetic Resonance Image (MRI)). The visualized stroke is a non-lacunar infarct , e.g. involving the cortex or >1.5 cm (>2.0 cm if measured on MRI diffusion-weighted images) in largest diameter if exclusively subcortical.Visualization by CT usually requires delayed imaging >24-48 hours after stroke onset.