A Study on the Correlation Between Clinical Features of Chronic Relapsing Inflammatory Optic Neuropathy and Myelin Oligodendrocyte Glycoprotein Antibodies

BACKGROUND: To compare clinical characteristics, cerebrospinal fluid (CSF) findings, relapse patterns, MRI features, visual outcomes, and optical coherence tomography (OCT) structural changes between MOG-IgG-positive and seronegative patients with chronic relapsing inflammatory optic neuritis (CRION). METHODS: I retrospectively reviewed patients diagnosed with CRION at the First Affiliated Hospital of Zhejiang Chinese Medical University between January 2015 and December 2021. All patients fulfilled established CRION diagnostic criteria, including recurrent optic neuritis, seronegativity for aquaporin-4 antibodies, optic nerve enhancement on MRI, and steroid-responsive relapse. Clinical, radiologic, CSF, and OCT data were compared between MOG-IgG-positive and seronegative patients. RESULTS: Forty-eight patients (77 affected eyes) were included, of whom 30 (62.5%) were MOG-IgG positive and 18 (37.5%) were seronegative. MOG-IgG-positive patients were younger at onset and more likely to present with ocular pain, bilateral involvement, and optic disc swelling. They had more frequent intraorbital and canalicular optic nerve involvement on MRI, a shorter interval to the second attack (3.44 ± 2.52 vs 13.84 ± 1.12 months, P < 0.001), a higher annualized relapse rate (0.478 ± 0.35 vs 0.175 ± 0.24 relapses/person-year, P < 0.001), and a higher proportion receiving immunosuppressive therapy (86.7% vs 55.6%). Seronegative patients had higher CSF protein and IgG levels and thinner average, superior, and nasal peripapillary retinal nerve fiber layer thickness on follow-up OCT. Visual acuity at nadir and at the final follow-up did not differ significantly between groups, and no cases of legal blindness were observed. CONCLUSIONS: MOG-IgG-positive and seronegative CRION patients exhibit distinct clinical, radiologic, relapse, and structural profiles. MOG-IgG positivity identifies a subgroup with earlier and more frequent relapses requiring close monitoring and potential early maintenance immunotherapy, whereas seronegative CRION is associated with greater structural optic nerve damage despite lower relapse frequency. These findings emphasize the heterogeneity of CRION and support antibody-based stratification for clinical management.