The bile ducts form an architected bile transport system. This liquid, produced by the cells of the liver and conveyed into the bile ducts in vessels of increasing caliber, is concentrated in the gall bladder and finally poured into the small intestine to favor the digestion of food lipids.
From the synthesis in hepatocytes (liver cells) to the outlet in the duodenum, the bile is conveyed in vessels of caliber gradually increasing, according to the following scheme:
Canaliculi or capillaries Biliary → Cholangioli or ductile Hering → Interlobular bile ducts → Intrahepatic bile ducts → Lobar hepatic ducts (right and left) that merge to form → the common hepatic duct, which exits the liver and joins with → the cystic duct (coming from the gallbladder) forming → the common bile duct (or common bile duct, 7 centimeters long and half) → which joins with the pancreatic duct → forming the ampulla of Vater → and entering the duodenum.
The common hepatic duct and the common bile duct are two segments of a single channel. In fact, between one meal and another, bile from the lobar hepatic ducts enters the common hepatic duct and deviates into the gall bladder, where it is accumulated and concentrated. After a meal, when the intestine needs bile to emulsify the fats and allow digestion, the gall bladder (or gallbladder) contracts by pouring the accumulated bile into the duodenum. Everything is favored by the presence of a sphincter, the so-called sphincter of Oddi, at the outlet point in the small intestine; while during the fasting this muscular ring is contracted, after meals it relaxes to allow the passage of bile in the intestine (contracted gall bladder -> open sphincter; relaxed gall bladder -> closed sphincter).
The outflow of bile into the bile ducts can be obstructed at various levels by tumors, stones or stenosis (abnormal shrinkage). One speaks in this case of cholestasis, a condition often associated with jaundice, that is to the yellow coloring of the skin and ocular sclerae due to the excessive passage in the circulation of the biliary bilirubin.
| EXTRAEPATHIC COLESTASI (causes) | COLESTASI INTRAEPATICA (causes) |
Bile duct tumors cysts Stenosis of the bile ducts Calculations in the common hepatic duct pancreatitis Pancreatic tumors or pseudocysts Tumor masses in adjacent organs Primitive sclerosing cholangitis | Alcohol abuse liver disease Amyloidosis Bacterial abscess in the liver Lymphoma, primary or secondary liver tumors Pregnancy (obstetric cholestasis) Primary biliary cirrhosis Primitive sclerosing cholangitis Sarcoidosis Sepsis Tuberculosis Acute viral hepatitis Sjögren syndrome |
