Diagnostic value
The second study, presented at the meeting by coinvestigator Brian Renner, MD, Department of Neurology at Cedars Sinai, Los Angeles, reported on the significance of the rim lesions in MS diagnosis. It included 95 patients who had presented for new evaluation on suspicion of MS at 10 centers in the North American Imaging in MS Cooperative (NAIMS).
Of these participants, 44 (46%) were positively diagnosed according to McDonald 2017 criteria (MC2017) for MS, while 37 (39%) were given an alternative diagnosis to MS. Fourteen were considered at risk for MS with diagnoses of clinically isolating syndrome or radiologically isolating syndrome.
Overall, among the 44 with an MS diagnosis, 34 had one or more rim lesions; among the 51 who did not meet an MS diagnosis, only six had one or more of the rim lesions. One or more rim lesions were further observed in three patients with radiologically isolating syndrome and one patient with clinically isolating syndrome.
Among those with one or more of the rim lesions, a diagnosis of MS with MC2017 MS criteria was identified with a high sensitivity of 80%, high specificity of 88%, accuracy of 84%, and an AUC of 81%.
“We’ve shown that paramagnetic rim lesions are highly specific for MS, and the sensitivity of rim lesions for MS is higher than previously reported, despite similar techniques in rating, processing, and evaluation – which was likely related to the nature of the cohort,” Dr. Renner said.
Promising data
During the NAIMS symposium, Christopher C. Hemond, MD, assistant professor or neurology at the University of Massachusetts Medical School, Worcester, noted to meeting attendees that the rim lesions were seen across the entire course of the MS disease spectrum, spanning from radiologically isolating syndrome to secondary progressive MS.
“We know paramagnetic rim lesions are visible at all disease stages. They are uniquely larger and more destructive than their rimless peers and are associated with stronger disease severity,” said Dr. Hemond, who was not involved with the research.
“There is promising data at this point suggesting that [the rim lesions] may represent a biomarker predictive of future disability accumulation,” he added.
Dr. Hemond noted that, unlike in Dr. Renner’s study, the bulk of previous studies have indicated that rim lesions “are associated with a high specificity but only modest sensitivity, in the mid-50% range, for the diagnosis of MS in comparison to some conditions that mimic MS.”
Commenting on the findings, Dr. Hemond noted the results from Dr. Renner’s ongoing study “are critical in building confidence in the translational use of this biomarker to assist in ruling in a diagnosis of MS,” while Dr. AlTokis’ study “adds to and is consistent with the growing literature of pathological associations of paramagnetic rim lesions in MS.”
Dr. Hemond added that the NAIMS cooperative plans to publish guidance in the area in the coming months.
“Although paramagnetic rim lesions have strong pathological associations in MS, it remains unclear if the presence of these lesions should change MS clinical management at the present time,” he said.
During the NAIMS session, Francesca Bagnato, MD, PhD, Vanderbilt University Medical Center, Nashville, Tenn., noted the growing importance of the role of rim lesions in clinical research. “It is clear that these paramagnetic rim lesions are going to be the new biomarker for the next generation of clinical trials,” she said.
Dr. Renner’s study received funding from the Race to Erase MS Foundation. Dr. AlTokhis, Dr. Renner, and Dr. Hemond have reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.