MOGAD Is the Most Common Cause of Isolated Optic Neuritis in Children

OBJECTIVES: The study aimed to characterize the clinical features, etiologies, and outcomes of isolated, first-time pediatric ON in the post-MOG-IgG era. METHODS: This was a single-center retrospective cohort study at Texas Children's Hospital of patients diagnosed with first-time ON between 2018-2024, with follow-up data collected through 2025. Inclusion criteria required monocular or binocular subacute vision loss with supportive paraclinical signs. Subjects were excluded if they had a prior history of demyelinating disease or extra-orbital demyelinating lesions on initial brain/spine MRI. Primary outcomes were the proportion of MOG-IgG seropositivity, retinal nerve fiber layer thickness, and visual acuity at onset and most recent follow-up. RESULTS: = 0.32, p < 0.01). One (3.7%) MOGAD-ON patient relapsed during follow-up. INTERPRETATION: In isolated pediatric ON, no patients were diagnosed with MS, and MOGAD is the predominant etiology. The linear correlation between initial LogMAR and subsequent RNFL atrophy suggests a permanent reduction in neurological reserve dependent on the degree of functional severity at ON onset.