Superior segmental optic nerve hypoplasia.

A visually asymptomatic 27-year-old man was found to have inferior altitudinal visual field defects binocularly. Ophthalmoscopy revealed superior segmental optic pallor with superior nerve fiber layer atrophy, nicely highlighted in red-free photographs. The patient's mother had insulin-dependent diabetes mellitus. Recognition of this entity is important for prognosis and for avoidance of unnecessary diagnostic studies.