Longitudinally Extensive Optic Neuritis in Pediatric Patients

Optic neuritis (ON) may herald the onset of multiple sclerosis (MS), neuromyelitis optica (NMO), or other autoimmune conditions. Extensive optic nerve lesions on MRI may indicate a diagnosis other than MS with worse prognosis, as is the case for extensive spinal cord lesions, which predict NMO. We introduce a definition of longitudinally extensive ON and report its frequency in children with first events of ON ultimately diagnosed with a neuro-immunological disease.