Congenital defect of the bony orbit and pulsating exophthalmos

Defects of the bony orbit are rare in childhood; therefore, when they are encountered in association with clinical signs and symptoms or as an incidental observation, various diagnostic possibilities arise. This consideration is not given to certain specific entities capable of being suspected on clinical grounds. Experiences with two instances of this rare anomaly have prompted us to report the problems presented and their management. The embryology and anatomy of the orbit are available in standard textbooks * and will not be discussed here. However, it is proper to note that both membranous bone and cartilaginous bone enter into the formation of the orbit, and that several natural apertures provide communication with the cranial cavity. Report of Cases Case1.—A white boy was born on April 5, 1944. He was the first child of young healthy parents. The pregnancy and delivery were not unusual; no disease during pregnancy was recorded. No