61 msfocusmagazine.org Gray matter lesions differ from white matter lesions Gray matter lesions differ from white matter lesions pathologically and functionally. When compared with white matter lesions, gray matter lesions are: • Less inflammatory • Small and primarily occur in the cerebral cortex, basal ganglia, and gray matter of the spinal cord and brainstem • Hard to distinguish from normal surrounding tissues of the brain rather than later. In addition, those diagnosed with CIS and/or RIS, who are at high-risk for developing clinically-defined MS, should also be treated with DMTs sooner rather than later. Several clinical trials have provided proof of concept foran earlywindowof first treatment intervention in patients with CIS. Significant reductions (39-50 percent) in the risk of developing clinically definite MS were observed with the interferon-beta products and glatiramer acetate when early treatment was initiated. Physical disability and number of brain lesions was also improved with early treatment. Similar results have also been observed with some of the newer DMTs (e.g., teriflunomide, alemtuzumab, and fingolimod).