Recently Published s troke t rials: What the Radiologist Needs to Know 1

n the span of several months, con- vincing evidence for the effectiveness of acute, intra-arterial stroke inter- vention has emerged. The release of the data from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Neth- erlands (MR CLEAN) triggered early interim analyses of three additional tri- als, Endovacular Treatment for Small Core and Anterior Circulation Proximal Occlusion with Emphasis on Minimizing CT to Recanalization Times (ESCAPE), Extending the Time for Thrombolysis in Emergency Neurologic Deficits-Intra- Arterial (EXTEND-IA), and Solitaire With the Intention for Thrombectomy as PRIMary Endovascular Treatment Trial (SWIFT PRIME) (1-4). In each of these four randomized controlled trials, investigators conclusively demonstrated that, in select patients, intra-arterial re- canalization in addition to intravenous administration of tissue plasminogen activator is superior to intravenous ad- ministration of tissue plasminogen ac- tivator alone in the treatment of acute ischemic stroke secondary to a large vessel occlusion. While the primary end points of these trials are clinical in nature, numerous features of the tri- als are focused on imaging and image- guided intervention. The sheer volume of data emerging from these trials is likely overwhelming to radiologists. As such, in this brief report we discuss the salient clinical findings from these four studies, with emphasis on the role of imaging in the selection of patients for mechanical thrombectomy (Table 1).