Park KA, et al. - Researchers estimated 111 candidates for a mean follow-up duration of 4.1 ± 3.1 years to elucidate the incidence and timing of recurrence in subjects with optic neuritis (ON). They calculated cumulative incidence of recurrence in either eye: 26% at 1 year, 33% at 3 years, 37% at 5 years, and 50% at 10 years after the first episode of ON. They also noted a relapse within 1 month and the presence of neuromyelitis optica-immunoglobulin G which developed the recurrence rate over time. Cumulatively, they observed 7 relapses after intravenous methylprednisolone treatment. They indicated a lower possibility of recurrence in subjects with longer recurrence-free follow-up period.