Journal of Neuroradiology (2015) 42, 133—140 Available online at ScienceDirect www.sciencedirect.com REVIEW OFSEP, a nationwide cohort of people with multiple sclerosis: Consensus minimal MRI protocol F. Cotton a,*,b , S. Kremer c , S. Hannoun b , S. Vukusic d , V. Dousset e,f,g , for the Imaging Working Group of the ‘‘Observatoire franc ¸ais de la sclérose en plaques’’ (OFSEP) a Service de radiologie, hospices civils de Lyon, centre hospitalier Lyon Sud, Pierre-Bénite, France b Inserm U1044, université de Lyon, université Lyon 1, CREATIS, CNRS UMR 5220, Villeurbanne, France c Service d’imagerie 2, FMTS, université de Strasbourg, hôpital de Hautepierre, ICube UMR 7357, CHU de Strasbourg, Strasbourg, France d Service de neurologie A et fondation Eugène-Devic EDMUS pour la sclérose en plaques, hôpital neurologique, hospices civils de Lyon, Bron, France e Institut de bio-imagerie de Bordeaux UMS 3428, University of Bordeaux, Bordeaux, France f Inserm, U862, physiopathologie de la plasticité neuronale, Bordeaux, France g Service de neuroimagerie diagnostique de thérapeutique, CHU de Bordeaux, Bordeaux, France Available online 7 February 2015 KEYWORDS Multiple sclerosis; Magnetic resonance imaging; Cohort studies; Consensus development conferences as topic Summary Multiple sclerosis (MS) is most generally considered as a severe disease with high physical and mental risks of disability. Since the end of the 1990s, several high cost long-term disease-modifying treatments provided some clinical efficiency. However, patient’s follow-up was needed for the detection and the assessment of their side-effects. The ‘‘Observatoire franc ¸ais de la sclérose en plaques’’ (OFSEP) project aims to improve the clinical, biological and imaging systematic longitudinal follow-up of patients. It should increase the quality, efficiency and safety of patients’ care, with a unique opportunity of large scale, about 41,000 patients followed in 62 French centers using the European Database for Multiple Sclerosis (EDMUS) soft- ware. OFSEP is divided into three working groups (clinical, biological and imaging). The imaging working group defines standards for routine MRI follow-up in the whole cohort and contains three Abbreviations: ADC, Apparent Diffusion Coefficient; BBB, blood brain barrier; CSF, cerebrospinal fluid; DTI, Diffusion Tensor Imaging; EDMUS, European Database for Multiple Sclerosis; FLAIR, fluid attenuated inversion recovery; IRC, Imaging Resource Centre; MRI, Mag- netic Resonance Imaging; MS, multiple sclerosis; OFSEP, French Observatory of Multiple Sclerosis (‘‘Observatoire franc ¸ais de la sclérose en plaques’’); PD, proton density; STIR, Short Tau inversion recovery. ∗ Corresponding author. E-mail address: francois.cotton@chu-lyon.fr (F. Cotton). http://dx.doi.org/10.1016/j.neurad.2014.12.001 0150-9861/© 2015 Elsevier Masson SAS. All rights reserved.