TY - INPR A1 - Elliott, C A1 - Wolinsky, JS A1 - Hauser, SL A1 - Kappos, L A1 - Barkhof, F A1 - Bernasconi, C A1 - Wei, W A1 - Belachew, S A1 - Arnold, DL KW - Chronic active lesions KW - progressive multiple sclerosis KW - relapsing multiple sclerosis KW - slowly expanding/evolving lesions KW - smoldering plaques JF - Multiple Sclerosis Journal UR - https://doi.org/10.1177/1352458518814117 SN - 1477-0970 N2 - BACKGROUND:: Chronic lesion activity driven by smoldering inflammation is a pathological hallmark of progressive forms of multiple sclerosis (MS). OBJECTIVE:: To develop a method for automatic detection of slowly expanding/evolving lesions (SELs) on conventional brain magnetic resonance imaging (MRI) and characterize such SELs in primary progressive MS (PPMS) and relapsing MS (RMS) populations. METHODS:: We defined SELs as contiguous regions of existing T2 lesions showing local expansion assessed by the Jacobian determinant of the deformation between reference and follow-up scans. SEL candidates were assigned a heuristic score based on concentricity and constancy of change in T2- and T1-weighted MRIs. SELs were examined in 1334 RMS patients and 555 PPMS patients. RESULTS:: Compared with RMS patients, PPMS patients had higher numbers of SELs ( p?=?0.002) and higher T2 volumes of SELs ( p?<?0.001). SELs were devoid of gadolinium enhancement. Compared with areas of T2 lesions not classified as SEL, SELs had significantly lower T1 intensity at baseline and larger decrease in T1 intensity over time. CONCLUSION:: We suggest that SELs reflect chronic tissue loss in the absence of ongoing acute inflammation. SELs may represent a conventional brain MRI correlate of chronic active MS lesions and a candidate biomarker for smoldering inflammation in MS. ID - discovery10065984 N1 - This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. The images or other third party material in this article are included in the article?s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit https://creativecommons.org/licenses/by-nc/4.0/deed.en Y1 - 2018/12/19/ AV - public TI - Slowly expanding/evolving lesions as a magnetic resonance imaging marker of chronic active multiple sclerosis lesions ER -