Inclusion Criteria- Patients experiencing an anterior circulation brain infarction complicating the occlusion of the internal carotid artery or the first or second segment of the middle cerebral artery, as seen on CT or MR angiography, undergoing a multimodal brain imaging (DWI/PWI MRI or CTP) prior to a mechanical thrombectomy initiated within 6 hours after onset according to the current guidelines.
- Age ≥ 18 ans.
- Mechanical thrombectomy initiated within 6 hours after onset.
- Eligible patients may receive IV thrombolysis with rtPA within 4.5 hours after onset.
- Affiliation to the french social security.
- Patients undergoing multimodal brain imaging MRI : DWI and PWI, or CTP before the initiation of thrombectomy.
- Signature of the informed consent within 24 hours after treatment
Exclusion Criteria- Modified Rankin Scale estimated before the occurrence of brain infarction > 1.
- Inability to access the cerebral vasculature in the opinion of the neuro-interventional team.
- Contraindication to imaging with contrast agents.
- Any terminal illness such that patient would not be expected to survive more than one-year.
- Delay between imaging and beginning of thrombectomy > 90 minutes.
- Evaluation of the presence of Target Mismatch on MRI or CTP before treatment
- Patients placed under guardianship, curators and analogous institutions