Multiple sclerosis (MS) slowly evolving lesions (SELs) are defined on MRI as contiguous regions of pre-existing lesions with constant and concentric local expansion on conventional T1-weighted and T2-weighted images. Myelin-related changes using myelin water fraction (MWF) and magnetization transfer ratio (MTR) in SELs and non-SELs were measured over 192 weeks in patients with relapsing MS. SELs showed reduced myelin measures at baseline compared to non-SELs. Furthermore, over the 4 years, only SELs, and not non-SELs, showed a significant mean decrease in MWF and increase in T1. Both results are indicative of progressive demyelination in this subgroup of chronic lesions.
This abstract and the presentation materials are available to members only; a login is required.