Optic canal diameter in infantile osteopetrosis.

Infants with osteopetrosis may present early for ophthalmologic examination because of threatened visual impairment, primarily related to optic nerve compression. The authors describe two children with osteopetrosis who had narrow optic canals on orbital computed tomography. These canals were statistically narrower than those of newly developed, age-matched controls. Optic canal diameters, in addition to visual evoked potential data, may be helpful in determining prognosis.