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Absent ductus venosus fetal ultrasound
Agenesis of the ductus venosus (ADV) is a rare fetal vascular anomaly.
Epidemiology
According to the data obtained from the screening tests performed at 11-14 weeks of pregnancy, its incidence is reported to be 1/2500 .
Pathology
In a large case series, Acherman et al. defined five drainage patterns in absent ductus venosus:
- the umbilical vein is connected to the systemic venous circulation through the portal sinus
- via an abnormal venous channel from the portal sinus to the right atrium
- presumably via hepatic sinusoids to the hepatic veins
- the umbilical vein bypasses the portal sinus and the liver and connects to the systemic venous circulation via an abnormal venous channel
- from the umbilical vein to the right atrium, directly or through a dilated coronary sinus: considered the most common type and carries the worst prognosis due to the risk of developing congestive cardiac failure
- from the umbilical vein to the midportion of the inferior vena cava (IVC)
- from the umbilical vein to the right iliac vein
Associations
- development of hydrops fetalis
- fetal aneuploidy
- focal liver necrosis and calcification
- chromosomal anomalies, e.g. Turner syndrome
- non-aneuploid syndromic anomalies, e.g. Noonan syndrome
- non-syndromic anomalies, e.g. congenital cardiac anomalies
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