The clinical features, MRI findings, and outcome of optic neuritis in children

Background: Optic neuritis (ON) in childhood is thought to be more likely bilateral and less likely to lead to multiple sclerosis (MS) vs ON in adults. Methods: The authors evaluated clinical features, maximal visual deficit and recovery, visual evoked potentials (VEPs), neuroimaging, and outcome in a cohort of children with ON. Results: Records of 36 children (female/male ratio 1.6), ages 2.2 to 17.8 (mean 12.2) years, were reviewed. ON was unilateral in 58% and bilateral in 42%. Maximal visual deficit was severe in 69%, but full recovery occurred in 39 of 47 affected eyes (83%). VEPs were abnormal in 88%. Neurologic abnormalities in addition to those associated with ON were documented in 13 children. Neuroimaging studies of the optic nerve were abnormal in 55%. Brain MRI in 35 children demonstrated white matter lesions separate from the optic nerves in 54%. Follow-up is 2.4 years (0.3 to 8.3 years). To date, 13 children (36%) have been diagnosed with MS and 1 has Devic disease. Bilateral ON was more likely to be associated with MS outcome (p = 0.03). All 13 children with MS had white matter lesions on brain MRI. None of the children with a normal brain MRI have developed MS to date. Conclusions: Contrary to expectations, optic neuritis (ON) in childhood was more likely to be unilateral, multiple sclerosis (MS) risk was high (36% at 2 years), and bilateral rather than unilateral ON was associated with a greater likelihood of MS. Clinical findings extrinsic to the visual system on baseline examination (p < 0.0001) and MRI evidence of white matter lesions outside the optic nerves (p < 0.0001) were strongly correlated with MS outcome.