Effect of new imaging parameters on combined recurrent events (including symptom progression and a distinct recurrent stroke).

CT/CTA metric: acute ischemia on CT, intracranial or extracranial occlusion or stenosis ≥50%. CT/CTA descriptors: white matter disease (presence of white matter hypodensities consistent with small vessel disease), prior stroke (evidence of previous cerebral infarction), aortic arch atheroma (focal area of protruding plaque ≥4 mm), ICA intraluminal thrombus (Internal carotid artery intraluminal thrombus – area of hypodensity surrounded by contrast on CT, consistent with an acute thrombus). MRI: Any white matter disease (any area of hyperintensity on the white matter on FLAIR sequence that is not part of an acute cerebral infarction), Prior stroke (evidence of prior stroke), microbleeds (small round area of hypointensity seen on gradient echo sequence).