Ultrasound in the evaluation of anencephaly

Three cases of anencephaly diagnosed in utero by ultrasound are presented and the ultrasound diagnostic criteria for anencephaly are illustrated. The literature regarding anencephaly is reviewed and the malformation discussed. Diagnostic ultrasound should be used to screen high-risk patients for this fetal anomaly. In addition, all patients clinically suspected of possible fetal malformation or polyhydramnios should be examined by ultrasound.