The vascular segment of the caudal vena cava of the dog at the level of the
caudate lobe was shown to be intimately related to hepatic tissue through
the hepatic capsule and parenchyma. The tunica adventitia of the caudal ven
a cava was formed mainly by smooth muscle cells with collagen and elastic f
ibers arranged in bundles. The thin tunica media of the vein was also forme
d by smooth muscle cells, collagen and elastic fibers arranged in bundles.
The tunica intima presented an elastic subendothelial network. The hepatic
segment of the caudal vena cava showed a myoconnective architecture and pro
pulsive characteristics in terms of its hemodynamic pattern.