Myelin dynamics in acute multiple sclerosis lesions: Short-term myelin water changes relate to long-term lesion outcome

Motivation: MRI allows visualization of brain changes in-vivo related to myelin and water content. Goal(s): To characterize short-term and long-term myelin and water content changes in new lesions in relapsing-remitting MS (RRMS). Approach: 20 people with RRMS were scanned monthly for 6 months and at ~5 years (11 participants). Myelin water fraction (MWF) and T1 were measured in 43 new lesions and followed longitudinally. Results: ~85% of new lesions showed an initial decrease in MWF at first appearance. Early MWF recovery, or lack thereof, during the first few months of lesion evolution may relate to the lesion MWF at 5 years. Impact: Early myelin water fraction dynamics in new multiple sclerosis may predict lesion MWF at 5 years.