Optic atrophy and the Wyburn-Mason syndrome.

A 14-year-old girl developed impaired vision and optic atrophy of the left eye as a manifestation of an orbital and parachiasmal arteriovenous malformation. Despite the lack of a retinal arteriovenous malformation, this condition appears to be a variant of the Wyburn -Mason syndrome, representing a vascular dysgenesis of the orbit and midbrain resulting in focal arteriovenous communications without interposed capillaries.