Cephalocele and cystic hygroma: diagnosis and differentiation in the first trimester of pregnancy with transvaginal sonography. Report of two cases

Two case reports are presented of fetuses with malformations in the neck region, detected in the first trimester of pregnancy by transvaginal ultrasonography. In one fetus a septated cystic hygroma was visualized. Trisomy 18 was found. The other fetus presented with a cephalocele. The ultrasound diagnosis was confirmed at autopsy in both cases. Sonographic criteria to distinguish between cystic hygroma and occipital cephalocele in the first trimester of pregnancy are discussed. Copyright © 1992 International Society of Ultrasound in Obstetrics and Gynecology