Résumé
Introduction: The treatment of severe optic neuritis (ON) is an emergency, and the role of therapeutic plasma exchange (PLEX) is still debated. The objective of this study was to evaluate the efficacy of the initial combination of parenteral corticosteroid therapy with therapeutic PLEX for the treatment of severe ON. This was a retrospective cohort study conducted between January 1998 and January 2023.Methods: Therapeutic PLEX was initiated concomitantly with intravenous corticosteroid therapy. The etiological diagnosis of ON was specified as follows: neuromyelitis optica, myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD), and multiple sclerosis. Sixty-five eyes (74.7%) underwent therapeutic PLEX, and 22 eyes (25.3%) received corticosteroid therapy alone.Results: The mean time to treatment was 7.9 ± 11 days. At 1 year, the mean visual acuity of plasmapheresis patients was 5/10, and that of non-plasmapheresis patients was 1.5/10 (p = 0.008). Five (8.1%) eyes in the PLEX group and 7 (31.8%) eyes in the group treated with corticosteroids alone remained completely blind (p = 0.005). The retinal nerve fiber layer and ganglion cell layer thickness were greater in the PLEX group than in the group treated with corticosteroids alone, 74 ± 23.1 μm versus 59.7 ± 19.3 μm and 24.7 ± 4.3 μm versus 23.3 ± 5.4 μm, respectively. MOGAD and multiple sclerosis patients had the best final visual acuity, 6/10 and 10/10, respectively (p = 0.01). No serious incidents were observed.Conclusion: This is the largest series of severe ON observed in an Afro-descendant population and treated concomitantly with therapeutic PLEX and systemic corticosteroid therapy at the acute phase. Our study confirms the efficacy of therapeutic PLEX in treating severe ON.