Expanding the therapeutic window in acute ischemic stroke by advanced imaging

The treatment in acute ischemic stroke has shown extensive improvement in these recent years by new endovascular devices and advanced imaging. Advanced imaging is mainly led by perfusion imaging and has been powered by automated analyzing software. In this manuscript, we describe the history and the technology of perfusion imaging, including parameters and analyzing methods that have evolved from positron emission tomography and single-photon computed tomography to computed tomography perfusion and magnetic resonance imaging perfusion. The immense clinical advantage of advanced imaging is expansion of the therapeutic window by various mismatch assessments. Of these, perfusion-weighted imaging - core mismatch has managed to demonstrate the evidence in randomized control trials. A unique understanding of conventional imaging such as diffusion-weighted image - fluid-attenuated inversion recovery mismatch has also played a role in expanding the therapeutic window to wake-up strokes or unwitnessed strokes. In this article, these mismatch assessed trials are described with future insights