Quantitation of craniofacial anomalies in utero: fetal alcohol and Crouzon syndromes and thanatophoric dysplasia.

The study of fetal growth and development by ultrasound has been greatly facilitated in the past few years by the availability of anthropometric standards for the fetal body. Thus, the obstetrician is able to discern between normal and grossly abnormal, and even to quantitate certain fine fetal structures such as the face. This paper presents results obtained from a group of 5 patients referred to the Medical Center from private practices in Indianapolis, Indiana. Prenatal cephalometric analyses by ultrasound suggested the presence of craniofacial anomalies in all 5 cases. However, such defects were not detectable by routine ultrasonographic examination. A clinical examination after birth of each of these 5 patients suggested the following diagnoses: Fetal Alcohol Syndrome (FAS) in 2 individuals, Fetal Alcohol Effects (FAE) in one individual, Crouzon Syndrome (CS) in one patient, and Thanatophoric Dysplasia (TD) in one patient. In order to compare the craniofacial measurement values for each patient to normal standards, we developed Z-Score profiles and Pattern Variability Indexes (PVI) as described by Garn et al. [1984, 1985]. The values presented here support the idea that even mildly abnormal fetal craniofacial patterns are detectable by this relatively new application of ultrasound. At the present time, no conclusions can be made regarding the diagnostic accuracy of these patterns and profiles. However, the potential value of fetal cephalometry for documenting craniofacial dysmorphology is clearly indicated.