MRI Techniques in Multiple Sclerosis: Role in Diagnosis, Pathophysiology, and Therapy

Multiple sclerosis (MS) is the most common chronic inflammatory-demyelinating disease affecting the central nervous system (CNS) of young adults in the western countries, leading, in the majority of cases, to severe and irreversible clinical disability (1). Since its clinical introduction, conventional magnetic resonance imaging (cMRI-dual-echo and postcontrast T1-weighted scans) has greatly improved our ability to diagnose MS and to monitor its evolution, either natural or modified by treatment (Fig. 1) (2). cMRI-derived measures have indeed shown several advantages over clinical assessment, including their more objective nature and increased sensitivity to MS-related changes. Nevertheless, the magnitude of the relationship between cMRI measures of disease activity or burden and the clinical manifestations of the disease is weak (3,4). This necessarily limits the role of cMRI for the understanding of MS pathophysiology and monitoring of experimental treatment.