HEPATIC HILAR AREA: THE PLATE SYSTEM

 The plate system consists of bile ducts and blood vessels
surrounded by a sheath that is continuous with Glisson’s
capsule, intrahepatically, and the hepatoduodenal
ligament, extrahepatically. This system also contains a
large number of lymphatics, nerves, and a small vascular
network. 
Couinaud  states that the bile ducts and
hepatic artery are located within the plate system, but
that the portal vein is covered with a separate sheath
of loose connective tissue, and that is why the plate
containing the extrahepatic bile duct and hepatic artery
can be easily separated from the portal vein. Three
plates are found in the hilar area: the hilar plate, the
cystic plate, and the umbilical plate

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