1. From the Multiple Sclerosis Centre of Catalonia (Cemcat) (C.T.), Department of Neurology, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Spain; NMR Unit, Queen Square MS Centre (C.T.), Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, United Kingdom; Neuroimaging Research Unit (M.A.R.), Institute of Experimental Neurology, Division of Neuroscience, and Neurology Unit, IRCCS San Raffaele Scientific Institute; and Vita-Salute...