Inclusion Criteria:  Patients with symptomatic or asymptomatic atheromatous stenosis of the internal carotid artery, of a degree ≥ 50%, for which an operative indication is retained Scheduled surgery  Exclusion Criteria:  Samples collected from patients :  who did not have a preoperative CT angiogram of the supra-aortic trunks with contraindication to MRI with contraindication to PET scan with a history of cervical radiotherapy with uncontrolled diabetes with a previous homolateral carotid endarterectomy who has already undergone angioplasty-stenting of the homolateral carotid artery with a neoplasia considered active / not cured Surgical procedure performed in emergency