Ann Neurol. 2023 Jun 21. doi: 10.1002/ana.26727. Online ahead of print.
ABSTRACT
OBJECTIVE: To determine early MRI features of new multiple sclerosis (MS) lesions that will develop into paramagnetic rim lesions (PRLs), which have been associated with progressive tissue injury in MS.
METHODS: New contrast enhancing lesions (CELs) observed on routine clinical MRI were imaged at 7-tesla (T) within 4 weeks of observation, and 3 and 6 months later. The 6-month MRI was used to classify PRL status (PRL or non-PRL). The relationship between early lesion characteristics and subsequent PRL status was assessed using generalized linear mixed effects models. Random forest classification was performed to classify early predictors of subsequent PRL status.
RESULTS: From 93 CELs in 23 MS patients, 37 lesions developed into a PRL. In lesions that developed into PRLs compared to those that did not, the average lesion T1 on the initial 7T MRI was 1994 ms compared to 1670 ms (p-value < 0.001) and the average volume was 168.7 mL compared to 44 mL (p-value < 0.001) in lesions that did not. These volume differences were also found on 3T scans (p-value < 0.001) and for intensity-normalized T1 -w (p-value = 0.011) and FLAIR (p-value = 0.005). The area under the receiver operating characteristic curve for the random forest classification with leave-one-out cross validation was found to be 0.86 using initial 7T features.
INTERPRETATION: New MS lesions that evolve into PRLs can be identified early in lesion evolution. These findings suggest that biological mechanisms underlying PRL development begin early, which has important implications for clinical trials targeting PRLs development and subsequent therapeutics. This article is protected by copyright. All rights reserved.
PMID:37345334 | DOI:10.1002/ana.26727
