Optic nerve hypoplasia with hypopituitarism and an arachnoid cyst.

We describe a 5-month-old boy with bilateral optic nerve hypoplasia associated with visual impairment, growth hormone deficiency and an arachnoid cyst in the right temporal lobe on MRI. Optic nerve hypoplasia is sometimes associated with agenesis of the septum pellucidum, commonly known as septo-optic dysplasia, and/or hypopituitarism. There have been a few reports about its association with other abnormalities of the central nervous system, but none about that with an arachnoid cyst.