Fetal development of the human orbit.

The development of the orbits in 70 human fetal skulls was investigated by measuring the width and height of the orbital entrance, as well as the volume and depth of the orbital cavity and the interorbital width. For determination of the orbital volume, we used the imprint method; the remaining parameters were estimated. Our measurements showed a linear growth rate for the orbital width, height, and depth. After transformation to the cubic root, the values of the orbital volume also demonstrated a linear increase. The orbital index (height/width x 100) expressed the change in the oval outline of the orbital entrance during fetal development from a flat, wide form to a nearly round form at birth. No statistically significant difference between the right and left orbit was found.