1 Mellen Center for Multiple Sclerosis Treatment and Research, Neurological Institute, Cleveland Clinic, Cleveland, OH, USA/Faculté de médecine, Université Saint Joseph de Beyrouth, Department of Neurology, Hôtel Dieu de France Hospital, Beirut, Lebanon.
2 Centre d'Esclerosi Múltiple de Catalunya (Cemcat), Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain.