Perfusion imaging in acute ischaemic stroke-the beginning of the end?

Endovascular thrombectomy (EVT) for large vessel occlusion in acute ischaemic stroke is the standard of care when initiated within 6 hours of stroke onset, and is performed between 6-24 hours using advanced neuroimaging (CT perfusion or MR imaging) for patients who meet the strict imaging selection criteria. However, adherence to the restrictive imaging criteria recommended by current guidelines is impeded in many parts of the world, including the UK, by resource constraints and limited access to advanced neuroimaging in the emergency setting. Furthermore, recent randomised and non-randomised studies have demonstrated that patients selected without advanced neuroimaging (with non-contrast CT and CT angiography only) using less restrictive imaging criteria for EVT eligibility beyond 6 hours from onset still benefited from EVT treatment, thereby increasing the proportion of patients eligible for EVT and widening the potential treatment impact at a population level. Hence, current guidelines should be updated expeditiously to reflect the level I evidence in support of more liberal imaging selection criteria for patients presenting with acute ischaemic stroke due to a large vessel occlusion.