Inclusion Criteria:  For patients with MS:  Patient over 18 years old Presenting MS defined according to McDonald's revised criteria for spatial and temporal clinical or radiological dissemination [16], Should benefit as part of the care of an MRI examination with or without injection of gadolinium Express consent to participate in the study Affiliate or beneficiary of a social security scheme  For patients with an indication to undergo a brain MRI and at low risk of inflammatory CNS disease:  Patient over 18 years old Should benefit as part of the care of an MRI examination with or without injection of gadolinium Express consent to participate in the study Affiliate or beneficiary of a social security scheme  Exclusion Criteria:  For patients with MS: Patient benefiting from a legal protection measure Pregnant or breastfeeding woman  For patients with an indication to undergo a brain MRI and at low risk of inflammatory CNS disease:  Patient benefiting from a legal protection measure Pregnant or breastfeeding woman Patient with inflammatory and / or demyelinating pathology of the CNS