Identification of Biomarkers in Ischemic Stroke - Clinical Trial

Inclusion Criteria: * For ischemic stroke : * Age \> 18-year-old * Ischemic stroke diagnosed on clinical presentation and cerebral imaging (CT or MRI imaging) * Inclusion inferior to 6 hours from stroke onset * Initial NIHSS score \> 0 at the time of clinical examination * Patients with multimodal imaging either through MRI or CT perfusion and supra-aortic vessels and intra-cerebral vessels (Willis circle) imaging \<0 * Procedure of signed consent in situation of emergency : consent of the patient if he has the possibility to sign or his representative if he is present * For hemorragic stroke : * Age \> 18 year-old * Hemorrhagic stroke diagnosed on clinical presentation and cerebral imaging (CT or MRI imaging) * Inclusion inferior to 6 hours from stroke onset * Initial NIHSS score \> 0 at the time of clinical examination * Hemorrhagic patients are paired for age and sex with ischemic patients * Procedure of signed consent in situation of emergency : consent of the patient if he has the possibility to sign or his representative if he is present For healthy controls : * Age \> 18 year-old * Stroke-free standardized questionnaire * Initial NIHSS score = 0 * Rankin score = 0 * High risk cardiovascular subjects * Controls are paired for age, sex and cardiovascular risk measured by a score (European Heart Score) with ischemic patients Exclusion Criteria: * Not affiliated to social security * Patient under legal protection or deprived of liberty by a judicial or administrative decision * Patient whose follow-up will be impossible * Prior stroke GROUP FOR ISCHEMIC STROKE : \- Patients with TIA and a negative cerebral CT or MRI GROUP FOR HEMORRAGIC STROKE : * Cerebral hemorrhage related to subarachnoid hemorrhage * Post-traumatic hemorrhage * Hemorrhagic transformation in patients with ischemic stroke GROUP FOR HEALTHY CONTROLS : \- Contraindication MRI