The ligamentum venosum is the fibrous remnant of the ductus venosus of the fetal circulation. Usually, it is attached to the left branch of the portal vein within the porta hepatis (gateway to the liver). It may be continuous with the round ligament of liver (ligamentum teres hepatis). It is invested by the peritoneal folds of the lesser omentum within a fissure on the inferior surface of the liver between the caudate and main parts of the left lobe. [ http://en.wikipedia.org/wiki/Ligamentum_venosum ]