Chiasmal optic neuritis in a 4-year-old girl: a case report and review of the literature.

We report a 4-year-old girl presenting with sudden severe bilateral visual loss. Ophthalmological examination revealed optic disc pallor. Further neurological examination was normal. Brain magnetic resonance imaging (MRI) suggested chiasmal optic neuritis, and further etiological investigations were negative. We review the literature on the incidence and underlying etiology of chiasmal optic neuritis in childhood.