Retrolental fibroplasia (R. L. F.) is an ocular disease usually associated with prematurity and usually affecting both eyes. The most conspicuous diagnostic sign is the presence of a membrane, often vascularized, situated behind the crystalline lens. The presence of blood vessels in the membrane serves to differentiate retrolental fibroplasia from congenital cataract. The affected eye may be smaller than normal, the anterior chamber shallow and the ciliary body abnormally serrated. Secondary changes, such as synechiae, glaucoma and iritis, frequently develop. The disease is rarely, if ever, seen at birth but develops when the infant is between 1 and 5 months of age. It has been seen to start as a dilatation of the retinal vessels followed by exudative retinitis and subsequent retinal detachment.1 Retrolental fibroplasia was first associated with prematurity by Terry2in 1942. Since then there have been indications that the incidence has increased more in some