Henry Gray (18251861). Anatomy of the Human Body. 1918.
the sinusoids empty themselves into one vein, of considerable size, which runs down the center of the lobule from apex to base, and is called the intralobular vein. At the base of the lobule this vein opens directly into the sublobular vein, with which the lobule is connected. The sublobular veins unite to form larger and larger trunks, and end at last in the hepatic veins, these converge to form three large trunks which open into the inferior vena cava while that vessel is situated in its fossa on the posterior surface of the liver.
3. The bile ducts commence by little passages in the liver cells which communicate with canaliculi termed intercellular biliary passages (bile capillaries). These passages are merely little channels or spaces left between the contiguous surfaces of two cells, or in the angle where three or more liver cells meet (Fig. 1094), and they are always separated from the blood capillaries by at least half the width of a liver cell. The channels thus formed radiate to the circumference of the lobule, and open into the interlobular bile ducts which run in Glissons capsule, accompanying the portal vein and hepatic artery (Fig. 1093). These join with other ducts to form two main trunks, which leave the liver at the transverse fissure, and by their union form the hepatic duct.
Structure of the Ducts.The walls of the biliary ducts consist of a connective-tissue coat, in which are muscle cells, arranged both circularly and longitudinally, and an epithelial layer, consisting of short columnar cells resting on a distinct basement membrane.
Excretory Apparatus of the Liver.The excretory apparatus of the liver consists of (1) the hepatic duct, formed by the junction of the two main ducts, which pass out of the liver at the porta; (2) the gall-bladder, which serves as a reservoir for the bile; (3) the cystic duct, or the duct of the gall-bladder; and (4) the common bile duct, formed by the junction of the hepatic and cystic ducts.
The Hepatic Duct (ductus hepaticus).Two main trunks of nearly equal size issue from the liver at the porta, one from the right, the other from the left lobe; these unite to form the hepatic duct, which passes downward and to the right for about 4 cm., between the layers of the lesser omentum, where it is joined at an acute angle by the cystic duct, and so forms the common bile duct. The hepatic duct is accompanied by the hepatic artery and portal vein.
The Gall-bladder (vesica fellea) (Fig. 1095).The gall-bladder is a conical or pear-shaped musculomembranous sac, lodged in a fossa on the under surface of the right lobe of the liver, and extending from near the right extremity of the porta to the anterior border of the organ. It is from 7 to 10 cm. in length, 2.5 cm. in breadth at its widest part, and holds from 30 to 35 c.c. It is divided into a fundus, body, and neck. The fundus, or broad extremity, is directed downward, forward, and to the right, and projects beyond the anterior border of the liver; the body and neck are directed upward and backward to the left. The upper surface of the gall-bladder is attached to the liver by connective tissue and vessels. The under surface is covered by peritoneum, which is reflected on to it from the surface of the liver. Occasionally the whole of the organ is invested by the serous membrane, and is then connected to the liver by a kind of mesentery.