Anatomy of retrohepatic segment of inferior vena cava and termination of hepatic veins.

BACKGROUND Information on anatomy of intrahepatic inferior vena cava (IVC) and hepatic vein openings in it is limited. METHODS We studied the retrohepatic segment of IVC and hepatic vein openings in it in 69 livers obtained from cadavers. The retrohepatic portion of the IVC was opened posteriorly by a vertical cut, the exposed surface was divided into 12 quadrants and the position, size, and septation of ostia of hepatic veins and any accessory openings were charted; measurements were made using Vernier calipers. RESULTS The median length of the intrahepatic IVC was 5.7 (range 3.3-8.2) cm and its median diameter was 2.3 (range 1.5-3.0) cm. The superior (major) set of hepatic veins comprised of two veins (right and left-middle) in 45 (65%) cases, three veins (right, middle, and left) in 23 (33%) and four veins in one (2%) case. Median diameter of the right hepatic vein was 1.5 (range 0.8-2.7) cm and that of left hepatic vein was 1.2 (0.7-2.6) cm. Middle hepatic vein, when separate, had a median diameter of 1.1 (range 0.5-1.5) cm. The inferior (minor) set of hepatic veins had two to 16 (median 7) veins. CONCLUSIONS Our data provide information on number, size, position, and septation of hepatic vein openings into the IVC. This information may be useful to hepatologists, hepatic surgeons while planning segmental resection of the liver, and to radiologists planning diagnostic and interventional procedures on hepatic venous system.