Abstract
Histology of the liver capsule and vascular sheath has not been examined in detail. In the porta hepatis, the portal vein, hepatic artery, hepatic duct and their associated nerves are embedded in the loose connective tissue. In contrast, segmental and subsegmental bile ducts are surrounded by the tight fibrous tissue that is located immediately outside of the liver capsule. The tight fibrous tissue may continue to the so-called Glisson's capsule. I speculate that, during surgery, the hilar plate isartificially developed from those connective tissues. The liver capsule adjacent to the tunica adventitia of the inferior vena cava contains abundant smooth muscles those exhibit a histology different from the tunica media. Near the inferior vena cava, the liver capsule smooth muscle extends along the hepatic vein tributaries and it mixed with the tunica media of peripheral veins such as the caudate vein.
