During the past decade ophthalmologists have pioneered advances in the knowledge of prenatal disease which have transcended the confines of their specialty and acted as a ferment on investigations by pediatricians, obstetricians, pathologists and students of public health. The first impetus came from the observations of Gregg on the permanent consequences to infants which follow rubella of the mother in early pregnancy.1A drastically altered point of view of physicians toward minor disorders of gestation was the result. The implications are that the principle at work is the key to many of the structural defects characteristic of the the developmental period of life.2Thus, Terry's demonstration3that retrolental fibroplasia is a defect not merely of infants, but for the most part of prematurely born infants, challenged further study and interpretation. Krause4established that the condition was generally associated with dysplasia of the brain—hence the name encephalo-ophthalmic