A BIOMETRIC STUDY OF THE EYE, ORBIT, AND FACE IN 205 NORMAL HUMAN FETUSES

PURPOSE. TO develop models for assessing the differential growth of th e fetal face along its horizontal and vertical axes, as well as of the orbit and the eye. METHODS. Normal human fetuses (n = 205), whose ges tational ages ranged from 15.5 to 41 weeks of amenorrhea, were examine d. Orbitofacial parameters were as follows: outer canthal distance, in ner canthal distance, palpebral fissure length, and oropalpebral dista nce. Ocular parameters were corneal diameter and axial length. Correla tions were tested among all parameters. Linear and polynomial regressi on analyses of gestational age and the orbitofacial and ocular paramet ers were used to develop models of growth. Differential patterns of gr owth in the face were investigated. RESULTS. The best correlation was found between palpebral fissure length and oropalpebral distance. The increase of each of the parameters studied could be accurately describ ed by a linear model. Sex had no detectable effect on these parameters . Compared with the skull, the face had a more rapid growth along the vertical axis. The palpebral fissure developed more rapidly than the e ye. CONCLUSIONS. The parameters that were studied in the fetal face, o rbit, and eye follow a roughly linear growth curve.