Liver

• Largest solid organ in body (after skin)
• Separated by diaphragm from pleura/lungs
• Posterio-inferior surface abuts against abdominal oesophagus, stomach, duodenum, hepatic flexure of colon and right kidney

Divisions

1. By falciform ligament (containing ligamentum teres = obliterated remains of left umbilical vein; ligamentum venosum = fibrous remnant of fetal ductus venosus - shunts blood from left umbilical vein to vena cava)
   • Anatomical Right lobe
   • Anatomical Left lobe
2. By vena cava
   • Morphological right lobe
   • Morphological left lobe

     Divided into segments (4 for each lobe)

Internal structure

• Made up of lobules, each with solitary central vein + tributaries
• Spaces between lobules = portal canals
• Branches of hepatic duct lie in portal canals and receive fine bile capillaries from liver lobules

Segmental anatomy

Peritoneal attachments

• Liver enclosed in peritoneum except for small posterior bare area
• Falciform ligament ascends to liver from umbilicus (to the right of midline) and bears ligamentum teres and
• Divaricates into into coronary , then triangular ligaments
• Lesser omentum arises from fissures of porta hepatis + attaches to lesser curvature of stomach

Biliary System

• R/L hepatic ducts fuse in porta hepatis to form common hepatic duct
• Joins with cystic duct (draining gallbladder) to form common bile duct [lie in free edge of lesser omentum = anterior border of the epiploic foramen of winslow]
• CBD passes behind duodenum to open into papilla on medial aspect of 2nd part of duodenum (majority of the time with the main pancreatic duct of Wirsung) at the ampulla of Vater containing the sphincter of oddi

Calot's triangle:

• Hepatic duct
• Cystic duct
• cystic artery

Gallbladder

• Normally holds about 50ml bile and acts as bile concentrator/reservoir
• Lies in fossa separaing right and quadrate lobes of liver
• Related inferiorly to duodenum and transverse colon
• Anatomically divided into: fundus, body, neck, opening into cystic duct
• In dilated and pathological gallbladders, pouch present on ventral aspect just proximal to neck called Hartmann's pouch
• Blood supply: cystic artery
• Venous drainage: via small veins directly into liver

  

• Embryology: diverticulum grows out from wall of duodenum, differentiates into hepatic ducts and liver; another diverticulum from the side of the hepatic duct bud forms the GB and cystic duct