COmparing CeNters ThRombectomy Aspiration STentretriever

Inclusion Criteria: * Subject experiencing an acute ischemic stroke in which imaging demonstrates a vascular occlusion located in the distal internal carotid artery (ICA) through the distal middle cerebral artery (MCA). * Subjects in which the aspiration technique is used for at least the first two thrombectomy passes per occluded vessel. * Subjects older than 18 yo. * Subjects with a prestroke modified Rankin scale of 0-2 and presenting with an NIHSS of 2-30. * Subjects that the operator feels may be treated with endovascular therapy * Subjects in which computed tomography (CT)/Magnetic Resonance Imaging (MRI) demonstrates an infarct size of less than 70cc on MRI or Alberta Stroke Program Early CT (ASPECTS) score overall of 6 or better. * Subjects in which groin puncture can be obtained within 6 hours of symptom onset (with or without Total Plasminogen Activator administration). In those Patients of more than 8 hours or awake stroke or of unknown onset should be individualized the treatment and must exist area of penumbra in CT perfusion * Subjects who have consented in accordance with local Institutional Review Board requirements Exclusion Criteria: * Absence of large vessel occlusion on neuroimaging. * Platelet count \< 100 x 10³ cells/mm³ or known platelet dysfunction. * Contraindication to CT and/or MRI (i.e., due to contrast allergy or prior implant that precludes MRI imaging). * Previously documented contrast allergy that is not amenable to medical treatment. * Women who are pregnant or breastfeeding at time of intervention. * Evidence of brain hemorrhage on CT and/or MRI at presenting hospital.