Fetal craniofacial morphometrics: in utero evaluation at 16 weeks' gestation.

Although ultrasound has proved useful in the diagnosis of fetal craniofacial malformations, its success has been based primarily on subjective clinical observations of apparent abnormal fetal structures, their proportions, and unusual features. However, such clinical observations may be misleading and ideally should be validated by standardized quantitative measurements. We describe here an ultrasonographic methodology that has provided quantitative data describing the normal fetal craniofacies at 16 weeks of gestation. This report is part of an ongoing research project directed at describing fetal facial morphology in utero at different gestational ages. Such data can be used to construct growth curves to which observations from suspected abnormal fetuses can be compared. A total of 53 patients were evaluated at 16 weeks of gestation, at which time 24 craniofacial linear and angular measurements were made. The landmarks employed for these measurements were those used in roentgencephalometry so that this fetal data base could be related to postnatal populations. Such data will contribute not only to a description of facial dysmorphogenesis but also to a better understanding of normal facial growth and development. Furthermore, they constitute a useful tool for prenatal diagnosis, gestational aging, growth predictions, and perhaps for as yet relatively unexplored fields such as fetal therapy.