Paraumbilical portosystemic anastomosis (caput medusae)
Termination
Small paraumbilical veins (of Sappey) run with the ligamentum teres in the falciform ligament from the left branch of the portal vein to the umbilicus, where they meet the superficial epigastric (to great saphenous and femoral), thoracoepigastric and lateral thoracic (to axillary), and superior and inferior epigastric veins. In portal hypertension the obliterated umbilical vein itself may recanalise and carry a large flow.
Traced from the start
- Inferior mesenteric veinShort gastric and left gastro-omental veins
- Jejunal, ileal, ileocolic, right colic and middle colic veinsRight gastro-omental and pancreaticoduodenal veins
- Oesophageal veins (lower third)
- Splenic veinSuperior mesenteric veinLeft gastric (coronary) vein
- Hepatic portal vein
- Paraumbilical portosystemic anastomosis (caput medusae)
Detail
- Portal limb
- Paraumbilical veins from the left portal branch, in the ligamentum teres
- Systemic limb
- Superficial and deep epigastric veins to the femoral vein (IVC) and axillary vein (SVC)
- Produces
- Caput medusae
When it goes wrong
Portal hypertension driving blood outward through the paraumbilical veins
Caput medusae: dilated periumbilical veins in which flow radiates away from the umbilicus, so that below the umbilicus it runs towards the legs
Inferior vena cava obstruction, by contrast
Dilated flank and abdominal wall veins in which flow below the umbilicus runs upward towards the head; emptying a segment and watching which way it refills separates the two
Recanalised umbilical vein carrying a large flow (Cruveilhier-Baumgarten syndrome)
Continuous venous hum, sometimes with a thrill, at the umbilicus of a patient with cirrhosis
Practise this structure
2 questions in the bank tagged Abdominal Wall.
A 71-year-old woman has coughed violently for 3 weeks. Yesterday, during a bout of coughing, she felt sudden tearing pain in the right lower abdomen and now has…
Foundations · middle twist
A 58-year-old builder has noticed a bulge in the right groin over 6 months. It appears when he coughs or lifts and disappears when he lies down. On standing, th…
Foundations · middle twist