Liver

• Liver


  The largest abdominal organ, a huge glandular organ belonging to the GI system

  
• The liver is about 2.5% of the body mass in adults, i.e. 1500 gm

  
• The liver receives 25% of cardiac output
• In the late fetus, the liver also serves as a hematopoietic organ and is proportionately twice as large (5% of body weight)

  
• In adults, the liver lies in the right hypochondrium, epigastrium, and left hypochondrium

  
• In normal individuals, the liver should not be palpable below the right costal margin

  
• Liver surfaces


  • Diaphragmatic surface (anterior, superior, and some posterior)
  • Visceral surface (posteroinferior)

  
• The liver is surrounded by Glisson's capsule, a strong connective tissue

  
• The liver receives venous blood returning from the GI tract through the portal vein, which is laden with the products of digestion, especially fats
• In addition to its many metabolic activities, the liver is a storehouse for glycogen and it secretes bile
• Embryology of the liver

  Developed from proliferation of blind end of a Y shaped diverticulum which grows from foregut into septum transversum

  
• Shape of the liver

  • Blunt wedge shaped with rounded base to the right
  • Oblong block with inferior surface shizzled away

  
• The inferior surface of the liver is set obliquely facing not only downwards but also backwards & to the left

  
• The posterior & inferior surfaces of the liver merge together to form the posteroinferior surface (visceral surface) as the distinction between them is difficult

  
• Functional division of the liver

  Functionally divided into two lobes, the left and right lobes, by a plane that passes through the gallbladder fossa and fossa for the IVC (Cantlie's line)

  
• Gross anatomical lobes of the liver

  Right, left, caudate and quadrate lobes divided by the surface peritoneal and ligamentous attachments

  
• Quadrate lobe


  • Lies between the fissure for ligamentum teres (left) and the gallbladder fossa (right), bounded posteriorly by the porta hepatis
• Caudate lobe


  • Lies between the fissure for the ligamentum venosum and the fossa for the IVC, functionally part of the left lobe but anatomically part of the right lobe, has a small tail-like caudate process
• Functional subdivision of the liver

  Has functionally independent right and left livers (parts or portal lobes) that are much more equal in size than the anatomical lobes, with the right liver still somewhat larger

  
• The caudate lobe may be considered a third liver as its vascularization is independent of the bifurcation of the portal triad and it is drained by one or two small hepatic veins entering the IVC

  
• Liver


  A peritoneal organ positioned in the right upper quadrant of the abdomen, the largest visceral structure in the abdominal cavity, and the largest gland in the human body
• Liver


  • Accessory digestion gland
  • Performs synthesis of bile, glycogen storage and clotting factor production
• Diaphragmatic surface


  The anterosuperior surface of the liver, smooth and convex, fitting snugly beneath the curvature of the diaphragm
• Visceral surface


  The posteroinferior surface of the liver, moulded by the shape of the surrounding organs, making it irregular and flat
• The posterior aspect of the diaphragmatic surface is not covered by visceral peritoneum and is in direct contact with the diaphragm itself (known as the 'bare area' of the liver)
• With the exception of the fossa of the gallbladder and porta hepatis, the visceral surface is covered with peritoneum
• Liver surfaces


  • Diaphragmatic surface
  • Visceral surface
• The liver is predominantly located in the right hypochondrium and epigastric areas and extends into the left hypochondrium
• Structures the visceral surface of the liver lies in contact with

  • Right kidney
  • Right adrenal gland
  • Right colic flexure
  • Transverse colon
  • First part of the duodenum
  • Gallbladder
• The liver is surrounded by numerous organs
• The liver is the largest visceral structure in the abdominal cavity
• The liver is the largest gland in the human body
• Liver


  The largest visceral structure in the abdominal cavity and the largest gland in the human body
• Liver


  • Accessory digestion gland
  • Performs synthesis of bile, glycogen storage and clotting factor production
• Structures the visceral surface of the liver lies in contact with

  • Right kidney
  • Right adrenal gland
  • Right colic flexure
  • Transverse colon
  • First part of the duodenum
  • Gallbladder
  • Oesophagus
  • Stomach
• Ligaments that attach the liver to surrounding structures

  • Falciform ligament
  • Coronary ligament (anterior and posterior folds)
  • Triangular ligaments (left and right)
  • Lesser omentum
• Falciform ligament


  Sickle-shaped ligament that attaches the anterior surface of the liver to the anterior abdominal wall, containing the ligamentum teres
• Coronary ligament


  Attaches the superior surface of the liver to the inferior surface of the diaphragm and demarcates the bare area of the liver
• Triangular ligaments


  Formed by the union of the anterior and posterior layers of the coronary ligament, attaching the left and right lobes of the liver to the diaphragm
• Lesser omentum


  Attaches the liver to the lesser curvature of the stomach and first part of the duodenum, consisting of the hepatoduodenal and hepatogastric ligaments