Contrast delay on perfusion CT as a predictor of new, incident infarct: a retrospective cohort study.

Background And Purpose: The purpose of this study was to determine if the assessment of intracranial collateral circulation by CT angiography and/or perfusion CT (PCT) can predict the risk of future ischemic stroke in a large, retrospective cohort study.

Methods: We identified 135 consecutive patients who underwent CT angiography of the head and neck and PCT of the brain at baseline and with subsequent follow-up brain imaging. Clinical and demographic information and carotid wall features were collected.