[ 4 ] “a persistence of portions of the omphalomesenteric (vitelline) venous system from the second month of fetal life is the most likely explanation for the portohepatic venous malformation.” Some small intrahepatic portosystemic shunts ( Table 1 ) located between the portal branches and hepatic veins disappear spontaneously by age 1 to 2 years [ 6, 7 ].
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