Possible way of spotting in clinic rim lesions known to drive progression
By Marisa Wexler, MS on 02/26/2024
An imaging feature called the T1-dark rim, which is visible on standard MRI scans of people with multiple sclerosis (MS), could help to identify paramagnetic rim lesions (PMLs), a study suggests.
PMLs are regions of chronic active inflammation that causes ongoing nerve damage. They’re associated with disease activity and are important drivers of disability progression in MS. Traditionally, advanced imaging techniques often beyond clinic use are needed to detect PMLs.
“The T1-dark rim could serve as an alternative marker to identify these lesions, thus potentially enhancing early detection and treatment adjustments for patients with MS at higher risk of disease progression,” the researchers wrote.
This imaging feature was described in the study, “The T1-dark-rim: A novel imaging sign for detecting smoldering inflammation in multiple sclerosis,” published in the European Journal of Radiology.
MRI scans in clinic can’t detect MS brain lesions of chronic, active inflammation
MS is caused by inflammation in the brain and spinal cord, resulting in areas of tissue damage and inflammation called MS lesions. These lesions are visible on MRI scans, and tracking how they evolve over time and in response to treatment plays a major role in guiding care decisions.
PMLs, also called iron-rim lesions or smoldering lesions, are a specific type of lesion marked by chronic active inflammation. These lesions contain a central core of pronounced myelin loss or demyelination, surrounded by a “rim” of immune cells that are continuously causing nerve damage.
PMLs have been identified as a highly specific marker of MS and studies suggest they may help predict disability worsening.
However, studies of PMLs detected these lesions using an advanced MRI protocol called susceptibility-weighted imaging or SWI. Although SWI has worked well in a research setting, it isn’t routinely done in MS clinical care, which has been a major obstacle toward the use of PMLs as a diagnostic and prognostic tool.
CLICK here to continue reading