MR and CT monitoring of recanalization, reperfusion, and penumbra salvage: everything that recanalizes does not necessarily reperfuse!

Revascularization therapies for acute stroke patients aim to rescue the ischemic penumbra by restoring the patency of the occluded artery ("recanalization") and the downstream capillary blood flow ("reperfusion"). This article reviews the definition of recanalization and reperfusion used in stroke clinical trials and their limitations and proposes a study design to determine the relative importance of recanalization, reperfusion, and collateral flow in evaluating the efficacy of revascularization therapies for acute ischemic stroke.