Objective: To determine the relationship between trisomies 13, 18, and 21 and craniofacial malformations detected by prenatal sonography.
Design: During a 29-year period (1976 through 2004), prenatal sonographic findings of 69 fetuses with trisomy 13; 171 fetuses with trisomy 18; 302 fetuses with trisomy 21; and 17 fetuses with other trisomies were evaluated retrospectively, after fetal karyotype identification. Sonographic findings were compared with autopsy results in 209 patients (trisomy 13, n=39; trisomy 18, n=64; and trisomy 21, n=106).
Results: For trisomy 13, cleft deformities were detected prenatally in 65.2%, and of the 39 cases with pathological information, 76.9% were found to have a cleft deformity. Ocular and orbital abnormalities were found in 28%. Malformations of the jaws and abnormal profiles were more frequently diagnosed postnatally than prenatally. For trisomy 18, abnormal profiles (41.5%) and ear abnormalities (5.3%) were the most noticeable ultrasound markers, next to abnormalities of the neurocranium (36.8%) and cranial bone configuration (21.6%). Dysmorphisms of the eye, ear, or nose were detected more frequently in autopsy cases. For trisomy 21, ultrasound showed an aberrant shape of the skull in 14.2% of fetuses. In general, the ocular-orbital and nasal abnormalities in fetuses with trisomy 18 or 21 were more evident in pathological examination than in prenatal ultrasound imaging.
Conclusions: Facial anomalies are common in the major trisomies, and their prenatal sonographic identification should be improved. The above-mentioned facial anomalies provide sufficient reason to consider performing cytogenic evaluation.