Associations Between Paramagnetic Rim Lesion Evolution and Clinical and Radiologic Disease Progression in Persons With Multiple Sclerosis

Abstract

BACKGROUND AND OBJECTIVES: Recent technological advances have enabled visualizing in vivo a subset of chronic active brain lesions in persons with multiple sclerosis (pwMS), referred to as "paramagnetic rim lesions" (PRLs), with iron-sensitive MRI. PRLs predict future clinical disease progression, making them a promising clinical and translational imaging marker. However, it is unknown how disease progression is modified by PRL evolution (PRL disappearance, new PRL appearance). This is key to understanding MS pathophysiology and may help inform selection of sensitive endpoints for clinical trials targeting chronic active inflammation. To this end, we assessed the longitudinal associations between PRL disappearance and new PRL appearance and clinical disability progression and brain atrophy. METHODS: -value). RESULTS: > 0.05). DISCUSSION: Our results show that resolution of existing PRLs and lack of new PRLs are associated with improved clinical outcomes. These findings further motivate the need for novel therapies targeting microglia-mediated brain inflammation and adoption of clinical strategies to prevent appearance of new PRL.