Feasibility Study of Phase-contrast MRI for Flow in the External Carotid Branches Arteries

Inclusion Criteria: * group 1 : healthy volunteer * group 2 : X-Ray treatment antecedent (at least 50 grays and older than one year) * group 3 : antecedent of embolization of branches of external carotid artery * group 4 : antecedent of muscular free flap surgery (older than one month) * free and informed consent Exclusion Criteria: * group 1 : facial pathology, antecedent of facial injury, antecedent of X-Ray treatment in head and neck localisation, antecedent of head and neck cancer * group 2 : antecedent of surgery for head and neck cancer or for vascular disease * group 3 : antecedent of surgery for head and neck cancer or for vascular disease ; antecedent of X-Ray treatment. * group 4 : antecedent of surgery for head and neck cancer or for vascular disease ; antecedent of X-Ray treatment or embolization * patient with guardianship or trusteeship * MRI cons-indications * pregnancy and lactation