Bilateral optic nerve hypoplasia associated with cerebral atrophy.

We present a series of 12 consecutive cases of optic nerve hypoplasia. Eight of these were unassociated with significant CNS malformations; of these, two had tomographic evidence of cerebral atrophy. This represents the first adequately documented cases of isolated cerebral atrophy associated with optic nerve hypoplasia. We discuss the increasing prevalence and marked variability of optic nerve hypoplasia, note the lack of clear distinction between primary failure of differentiation and secondary degeneration of optic pathways, and mention the inadequacy of the classic explanation of primary failure of ganglion cell development as the cause of hypoplastic nerves. The cause of cerebral atrophy are mentioned, and we hypothesize that the wide range of CNS insults resulting in atrophy may be responsible for a correspondingly wide range of abnormalities of the optic nerves. We speculate that cerebral atrophy may result in an inadequate cortical mass for induction of normal optic nerve growth, possibly by decreased retrograde axoplasmic flow and insufficient nerve growth factor. We encourage a complete neurologic evaluation, including CAT scan of the brain, in children with optic nerve hypoplasia.