Rajni Hospital, Ahmedabad, India.

Case report

This is a 20 weeks scan demonstrating agenesis of the ductus venosus. We also found minimal ascites with no other malformations. Inferior vena cava was dilated an its pulsation was visible. No cardiac malformation was detected, but actually a small ventricular septal defect was missed at that time.

At 24th week of pregnancy we found abnormal infrahepatic connection of the umbilical vein to the inferior vena cava. Ascites was not present at that time.

At 34th week the membranous ventricular septal defect was found.

The chromosomal analysis wasn"t done during pregnancy. The baby was delivered at 38th week of pregnancy by cesarean section for obstetrical reasons, and two days after delivery a Down syndrome was suspected. The baby was doing well during the first month of life, but was lost for following up after.

Images 1, 2: 2D sonography; 20 weeks of pregnancy. Image 1 - transverse plane through the fetal abdomen showing dilated umbilical vein with direct infrahepatic connection to inferior vena cava. Image 2 - sagittal thoracoabdominal plane showing the fetal ascites.

Image 3 and video 1: 3D reconstruction showing direct connection of the umbilical vein to the inferior vena cava (uv - umbilical vein; ivc - inferior vena cava; Des Aorta - descendent aorta).

Video 2 and 3: 2D ultrasonography. Video 1 - sagittal thoracoabdominal plane showing the dilated inferior vena cava and its connection to the right atrium; Video 2 - transverse plane at the fetal heart showing small membranous ventricular septal defect.

Image 4: Drawing shows various types of ductus venosus agenesis. The anomaly described above response to the drawing number 3. (1 - The normal umbilical vein to portal vein with the ductus; 2 - the suprahepatic connection to the inferior vena cava; 3 - the infrahepatic connection to the inferior vena cava; 4 - caput medusa in cutaneous anastomosis; 5 - the iliac connection; 6 - connection to the right atrium).