Multimodality CT based imaging to determine clot characteristics and recanalization with intravenous tPA in patients with acute ischemic stroke

Acute ischemic stroke (AIS) is a common neurovascular emergency causing significant burden to society. Currently the main focus of AIS treatment is to restore blood flow to at risk brain tissue. For the last twenty years, intravenous tissue plasminogen activator (tPA) was the only proven therapy for patients with AIS. More recently, five randomized clinical trials established the efficacy of endovascular therapy with or without intravenous tPA in selected patient populations with AIS. Not all stroke patients benefit from intravenous tPA or endovascular treatment. Nonetheless, the concept of early recanalization of occluded arteries resulting in better clinical outcomes is well established. In this focused review, we will discuss how imaging modalities such as Non-Contrast CT, CT-Angiography, and CT-Perfusion can potentially help physicians determine which patients are likely to recanalize early with intravenous tPA and therefore benefit from this therapy.