QSM Source Separation Detects Treatment Effect of Ocrelizumab on Multiple Sclerosis Lesion Myelin: A Longitudinal Study

Motivation: Noninvasive tools for monitoring the changes in tissue during treatment is an important clinical need. In Multiple Sclerosis (MS), estimation of iron and myelin content is essential. Goal(s): This study aims to demonstrate the potential of a newly developed technique for myelin and iron change detection during treatment from gradient-echo data. Approach: Data from 29 MS patient were retrospectively collected over a period of time that covers the treatment start and all data were processed to estimate iron and myelin biomarkers. Results: Statistical analyses showed that the Ocrelizumab treatment caused overall iron decrease and remyelination. Impact: Treatment efforts in Multiple Sclerosis includes medications that suppress acute inflammation. Therefore, the noninvasive quantification of the effect of treatment on the iron change and remyelination carries significant importance. Here, a novel gradient-echo based approach is tested for this purpose.