Optic nerve changes in hydrocephalus.

Although there is little evidence in the literature, it is widely believed that congenital hydrocephalus is only very rarely associated with papilloedema. This study, conducted on 200 consecutive cases (including 35 of secondary hydrocephalus), is probably the first report in the literature of optic nerve changes in a large series, and papilloedema in congenital hydrocephalus does not seem to be so uncommon after all. The importance of its early diagnosis, almost entirely dependent in children on objective features, cannot be over-emphasized in the management of hydrocephalus. Analysis of a few ophthalmoscopic signs in these eyes with papilloedema showed that presence or absence of the spontaneous or induced venous pulsations per se does not decide the diagnosis. The presence of venous engorgement seems to be a more definite and reliable indicator of early papilloedema.