Imaging parameters may aid in correctly differentiating neuromyelitis optica spectrum disorder (NMOSD) from multiple sclerosis (MS) and other inflammatory disorders that target the central nervous system, according to a study recently published in Neurology.
“A combination of cortical lesions, central vein sign and optic nerve markers achieves a high accuracy in distinguishing relapsing-remitting MS from APQ4-NMOSD and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) and when especially outside the acute phase, serologic testing is unavailable or ambiguous, or a false negative serological result is suspected, these markers can be of value to support the differential diagnosis,” the authors wrote.
This prospective study included 91 participants, among which 31 had a previous diagnosis of relapsing-remitting MS, 30 had NMOSD with positive aquaporin 4 antibodies, and 30 had MOGAD. The remaining 34 individuals served as the healthy control group.
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When comparing imaging patterns between patients with NMOSD and MS, the proportion of lesions with a positive central vein sign was the most accurate differentiating parameter, present in 33% vs 84% of the cases, respectively. Cortical lesions were another differing characteristic, ranging from 0 to 1 in NMOSD vs 1 to 14 in MS. White matter lesions were present with a mean of 9.5 among the individuals with NMOSD, while patients with MS had a mean of 39.07.
When using all 3 parameters together, both diseases could be distinguished with an accuracy of 95%, a specificity of 92%, and a sensitivity of 97%.
Similarly, MS can be differentiated from MOGAD by identifying a higher rate of white matter lesions, followed by cortical lesions. Retinal nerve fiber layer thickness also differed between the entities, with a mean of 87.54 in MS vs 75.54 in MOGAD. These 3 parameters showcased an accuracy of 95%, 84%, and 84%, respectively, for differentiating between these disorders.
“Our findings may be particularly useful in clinical practice to support a clinical diagnosis and exclude an antibody-mediated condition when the antibody testing is unavailable or suboptimal or when there is a suspicion of false negative/positive serologic testing results,” the authors concluded.
Cortese R, Prados F, Tur C, et al. Differentiating multiple sclerosis from AQP4-neuromyelitis optica spectrum disorder and MOG-antibody disease with imaging. Neurology. Published online October 3, 2022. doi:10.1212/WNL.0000000000201465