The gallbladder is a hollow, pear-like-shaped (piriform) organ that lies on the cystic plate (gallbladder bed) under the liver segments IVB and V. The cystic plate is a fibroareolar tissue that attaches the superior surface of the gallbladder to the liver.
- Location: intraperitoneal organ
Size and volume
- Length: 7–10 cm
- Width: 2.5 cm (at its widest point)
- Volume: 30–35 mL under normal conditions
- Can hold up to 300 mL if the cystic duct is obstructed
- Storage of bile
- Concentration of bile: by absorption of electrolytes and water
- Arterial blood supply: cystic artery (branch of the right hepatic artery)
- Venous drainage
- Sympathetic: via the celiac plexus
- Parasympathetic: Hepatic branch of the vagus nerve
- Sensory: fibers from phrenic nerve → hence referred pain to the right shoulder area (via C3 nerve fibers)
- The biliary tree is divided into the intrahepatic and extrahepatic bile ducts.
- Bile canaliculi →intrahepatic bile ductules (canals of Hering) → segmental bile ducts → sectional ducts
- The right and left hepatic ducts form the common hepatic duct.
- The common bile duct is formed by
Hepatobiliary triangle (Calots triangle)
- An anatomical space formed by the common hepatic duct, the cystic duct, and the lower border of the liver.
- The Calot triangle contains the cystic artery and the cystic lymph node (Lund's node).
- During cholecystectomy, the Calot triangle must be carefully identified to prevent damage to the cystic artery and extrahepatic biliary system.
- Common bile duct
- Bile pigments
- Primary bile acids: cholic acid, chenodeoxycholic acid
- Bile acids are conjugated with glycine (become water soluble).
Secondary bile acids: deoxycholic acid, lithocholic acid
- Synthesized in the intestinal lumen by action of bacterial flora
- Substances metabolized in the liver are excreted into the bile.
- Bile salts (95% of bile acids are reabsorbed back into the liver to be recycled)
Stones (for more information on gallstone pathologies, see and )
Cholesterol stones (75% of cases)
- Radiolucent with radiopaque areas due to calcifications (< 20%)
- Composed of calcium carbonate
- Pigment gallstones
- Cholesterol stones (75% of cases)
- Derived from endoderm
- Starts to develop during the 4th week of embryonic development
- Formed from the hepatic diverticulum (hepatic bud)