Perfusion computed tomography (CT) provides important information for patients with acute ischemic stroke by measuring cerebral blood flow, blood volume, and mean transit time to define the infarct core and potentially salvageable penumbra. While perfusion CT can help select patients for recanalization therapy and predict complications, current stroke guidelines have not included it due to limitations including variability between software and lack of validation in posterior circulation lesions. Further randomized studies are still needed to prove the benefits of perfusion CT in patient selection.