Prospective Registry of Endovascular Thrombectomy for eXtra-Large Ischemic Stroke

Inclusion Criteria: Clinical inclusion criteria 1. Age ≥18 years; 2. Presenting with acute ischemic stroke within 24 hours of time from last known well; 3. The patient or patient's representative signs a written informed consent form before enrollment. Neuroimaging inclusion criteria 1. Occlusion of internal carotid artery, or the middle cerebral artery M1 or M2 segments confirmed by computed tomography angiography, magnetic resonance angiography, or digital subtraction angiography; 2. The baseline ASPECTS is 0 to 2 based on NCCT or diffusion weighted imaging, or cerebral extra-large ischemic core volume ≥85ml (defined as relative cerebral blood flow \<30% on CT perfusion or an apparent diffusion coefficient \<620×10\^-6 mm2/s on MRI). Exclusion criteria 1. CT or MRI evidence of acute intracranial hemorrhage; 2. Evidence of mass effect with ventricular effacement, midline shift or herniation on baseline imaging; 3. Females who are pregnant, or those of childbearing, potential with positive urine or serum beta Human Chorionic Gonadotropin test; 4. Previous bleeding disorders, severe heart, liver or kidney disease, or sepsis; 5. Any terminal illness with life expectancy less than 6 months; 6. Participation in other clinical treatment trials.