Portal sinus

The portal sinus is an L-shaped venous confluence in the fetal circulation. It is located in the liver, between the left and right intrahepatic portal veins. The umbilical vein drains into the portal sinus at its medial aspect, near the left inferior intrahepatic portal vein 1,2. The ductus venosus then drains blood entering the portal sinus from the umbilical vein superiorly into the confluence of the hepatic veins into the inferior vena cava.

The portal sinus should be visible on axial images in the second-trimester obstetrical ultrasound during measurement of the abdominal circumference 3,4 .

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Article information

rID: 70617
System: Obstetrics
Section: Anatomy
Tag: stub
Synonyms or Alternate Spellings:
  • portal confluence
  • umbilical sinus

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