T1‐Dark Rim as a Marker of New and Chronic Active Multiple Sclerosis Lesions: A Serial Study With Frequent 7T MRI

作者：Madeleine Marshall, Kingkarn Aphiwatthanasumet, Olivier E. Mougin, Christine Stadelmann, Paul S. Morgan, Robert A. Dineen, Penny Anne Gowland, Nikos Evangelou, Margareta A. Clarke · 发表于：Journal of Neuroimaging · 年份：2025 · DOI：10.1111/jon.70044 · 被引用次数：3 · 研究领域：Multiple Sclerosis Research Studies、Systemic Sclerosis and Related Diseases、Cutaneous Melanoma Detection and Management

ABSTRACT Background and Purpose Chronic active multiple sclerosis (MS) lesions represent a particularly destructive subset of lesions on pathology. However, their imaging correlates, including paramagnetic rim lesions (PRLs) detected on susceptibility‐weighted imaging, lack sensitivity and are difficult to implement in clinical practice. This exploratory, longitudinal study investigates the prevalence and temporal dynamics of a novel imaging marker, T1‐dark rims, and their relationship with PRLs observed on quantitative susceptibility mapping (QSM). Methods Four untreated people with MS underwent 7‐Tesla MRI scanning six times over a period of 36 weeks. New and pre‐existing lesions were analyzed for the presence and temporal evolution of T1‐dark and QSM rims. Quantitative T1 values were derived using B1 maps, and the relationship between rim status and lesion size was evaluated. Results Of the 159 baseline lesions, 22 (14%) had T1‐dark rims, 11 (7%) had QSM rims, and five lesions had both. T1‐dark and QSM rims showed temporal changes, with T1‐dark rims preceding new QSM rim appearance in three out of four (75%) lesions. Eleven out of 20 (55%) newly formed lesions had T1‐dark rims, with a T1‐dark rim present in all new lesions over 100 mm3. Small new lesions lacked discernible rims, but their overall T1 values aligned with those of larger lesion T1‐dark rims implying shared pathological processes. Conclusions T1‐dark rims were more common than QSM rims, with greater prevalence...