Investigating the Frequency and Outcome of Central Vein Sign and Paramagnetic Rim Lesions in Children With MOGAD

BACKGROUND AND OBJECTIVES: Central vein sign (CVS) is a common feature in multiple sclerosis (MS) lesions, but its frequency in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) varies significantly across studies. Paramagnetic rim lesions (PRLs) are described in MS, but not in MOGAD. Our goals were to evaluate the prevalence of PRLs and CVS in a large multicenter cohort of pediatric MOGAD. We compared CVS frequencies between acute vs remission phases, as well as with longitudinal dynamics of lesion evolution. METHODS: In this longitudinal retrospective multicenter study, clinical MRIs were assessed from pediatric patients with MOGAD, who had (1) ≥1 brain lesion, (2) susceptibility-based imaging (SBI), and (3) follow-up MRI at least 3 months apart. T2-weighted and fluid-attenuated inversion recovery sequences were analyzed for lesion detection and resolution. SBI was used to assess CVS and PRLs following North American Imaging in MS Cooperative criteria. RESULTS: A total of 65 patients and 130 scans were included. A total of 520 lesions were evaluated. The most common reason for lesion exclusion was size (n = 143, large confluent lesions, n = 122, <3 mm, n = 21). CVS was detected in 97 of 327 (29.7%) lesions, with 32 of 65 (49.2%) patients having at least 1 CVS+ lesion. Patients with ≥1 CVS+ lesion (32/65, 49.2%) had a higher number of lesions (p = 0.002) and lesions suitable for CVS analysis (p < 0.001). Of the 31 patients with ≥3 brain lesions, 11 of 31 (35.5%) had >40% CVS+ lesions and 7 (22.5%) had >50% CVS+ lesions. Only 4 patients had ≥6 CVS+ lesions. The proportion of CVS+ lesions was lower in patients who had SBI acquired during an acute attack vs patients scanned during remission (16% vs 33%, p = 0.015). The rate of lesion resolution was higher in CVS- lesions (177/230, 76%) compared with CVS+ (42/97, 42%, p < 0.001). No PRLs were identified. DISCUSSION: Lesion pathobiology in MOGAD is heterogeneous. CVS identified persistent rather than transient lesions, with resolution more common among CVS- lesions. The high frequency of confluent or multivein lesions limited the proportion suitable for CVS analysis. MRI timing influenced CVS detection, which was higher in remission, suggesting that time of acquisition contributes to variability across MOGAD studies. No PRLs were found, supporting their potential as biomarkers distinguishing MOGAD from MS.