Inclusion Criteria:  To be over 18 year-old Perfusion MRI assessment on admission; Admission for an acute infarction of the anterior circulation with proximal occlusion (tandem, distal internal carotid, or M1 segment of the middle cerebral artery); Initial mTICI = 0-1 on the initial angiography before treatment; Patient in complete autonomy (mRS ≤ 2) before the onset of symptoms; Mechanical thrombectomy (in combination or not with intravenous thrombolysis), within the first 6 hours of the onset of symptoms, or within 24 hours in case of clinical-radiological or radiological mismatch; Success of reperfusion estimated by an mTICI = 3 at the end of the procedure; Availability of MRI within 3 hours of angiographic reperfusion; To be able to understand the instructions given; Written consent given by the patient or a trusted person; To be enrolled in a social security plan;  Exclusion Criteria:  Posterieur circulation obstruction; 3 months follow-up impossible with the completion of the MRI; Subject under a measure of legal protection