All patients will be treated within 90 minutes of the first slice of the baseline CT. Patients will undergo a study CT angiogram of the intracranial circulation between 4-8 hours after treatment to determine whether the occluded artery has recanalized or not. In sites where MRI/MRA is routinely used this can be substituted for CT/CTA. Any patient who has neurological worsening should have standard of care brain imaging completed to rule out intracranial hemorrhage.