Liver

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Questions

  1. What is the location of liver and how do you hold it in anatomical position? –
    1. The liver almost fully occupies the right hypochondrium, upper part of the epigastrium, and part of the left hypochondrium up to the left lateral (midclavicular) line.
    2. It lies mostly under cover of the ribs and costal cartilages immediately below the diaphragm.
    3. It extends upward under the rib cage as far as the 5th rib anteriorly on the right side (below the right nipple) and left 5th intercostal space anteriorly on the left side (below and medial to the left nipple).
    4.  In the midline, the upper border lies at the level of the xiphisternal joint.
    5. The sharp inferior border crosses the midline at the level of transpyloric plane (at the level of L1 vertebra;
  2. What are the external features of liver? Talk about Surfaces, Borders, Relations.
  3. Falciform ligament, Contents-
    1. Double layer of peritoneum
    2. Attached to anterior abdominal wall above the umbilicus and extends to the anterior surface of liver,
    3.  Posterior free margin contains Ligamentum teres hepatis(obliterated left umbilical vein)
  4. Porta hepatis – Contents –
    1. Posterior surface is separated from the inferior surface by an imaginary line drawn along the porta hepatis.
    1. Contains 3 structures-
      1. Anteriorly and to the right: Right and left hepatic ducts – leave the liver at hilum.
      2. Posterior most:  Right and left branches of portal vein – enters liver at hilum.
      3. Anteriorly and to the left: Right and left hepatic arteries – enters liver at hilum.
  5. Visceral relations
    • Formed by posterior and inferior surfaces of the liver
    • Left Lobe- Oesophagus and Stomach
    • Quadrate Lobe- Pylorus and D1
    • Fossa for gall Bladder- D2
    • Inferior Surface of Right Lobe of Liver- Hepatic Flexure of Colon
    • Posterior and Inferior surface of right lobe – Right kidney
    • Bare area of liver- Right suprarenal gland
    • Bare area – Boundaries – Clinical importance
    • Ligamentum teres hepatis –Embryological remnant
  1. Ligamentum venosum- Embryological significance-
    • Obliterated Ductus Venosus
    • Connects left branch of portal vein to the inferior vena cava in foetal life to bypass the liver.
  2. Peritoneal ligaments-
    • Ligaments of the liver are of two types: (a) false and (b) true. False Ligaments The false ligaments are actually peritoneal folds
    • Falciform ligament
    • On the superior surface, the two layers of  falciform ligament separate and go towards the diaphragm.
    • They get reflected back from the diaphragm to continue as the visceral peritoneum of the liver. This forms-
      • Superior layer of coronary ligament
      • Right triangular ligament
      • Left triangular ligament
    • Reflection of Visceral layer back towards the diaphragm to continue as parietal peritoneum forms the Inferior Layer of Coronary Ligament.
  3. Tributaries of IVC in liver- left, middle and right hepatic veins.
  4. Parts of gall bladder-
    • Fundus,
      • Fundus lies corresponding to tip of 9th costal cartilage
      • Infection of gall bladder- murphy’s sign can be elicited
    • body,
    • Neck-
      • Hartman’s pouch- where gall stones are lodged
      • Cystic duct- guarded by Valve of Heister
      • Cystic duct + hepatic duct = Bile Duct (doubt) – opens into D2
  5. Lobes of liver and blood supply of liver
    • Anatomical Division of Lobes-
      • Large right lobe
      • Small left lobe
      • Divided by:-
        • Attachment of falciform ligament on anterior surface
        • Fissure for ligamentum venosum on posterior surface
        • Fissure for ligamentum hepatis on inferior surface
    • Caudate Lobe-
      • Present on posterior surface of right lobe of liver
      • Bounded by-
        • Groove for IVC on right
        • Fissure for ligamentum venosum on left
        • Porta hepatis inferiorly
      • Caudate process-
        • Connects right lobe to caudate lobe
        • Forms the roof of epiploic foramen
      • Inferiorly and to the left presents a small rounded process called Papillary Process.
    • Quadrate Lobe-
      • Situated on the inferior surface of the right lobe of the liver
      • Rectangular in shape and hence the name Quadrate.
      • Boundaries-
        • Fossa for gall bladder on right side.
        • Fissure for ligamentum teres hepatis on left
        • Inferior border anteriorly
        • Porta hepatis posteriorly
    • Left Lobe-
      • Much smaller than right lobe
      • Forms only 1/6th of liver
      • Omental tuberosity-
        • A rounded elevation present near fissure for ligamentum venosum
    • Arteria Supply: Hepatic arteries and portal vein
    • Venous Drainage: hepatic veins which drain into IVC
    • Liver being a  foregut    derivative is supplied by the coeliac trunk. (Each part of gut tube has an artery. Foregut- Coeliac trunk, Midgut- Superior Mesenteric Artery, Hindgut- Inferior mesenteric artery)
    • Right and left hepatic artery enters liver at porta hepatis
    • Only 20% of liver blood supply is from hepatic arteries.
    • Remaining 80% of blood supply is from the portal vein.
  6. Clinical anatomy-
    1. Murphy’s point- notch on inferior border
      • At tip of Rt 9th Costal Cartilage
      • Murphy’s Point- Site of Maximum Tenderness in case of Inflammation of Gall Bladder
    1. Bare Area-
      1. Porto caval anastomosis
      2. In needle biopsy of the liver, the needle is inserted in the midaxillary line through 9th or 10th intercostal space. The needle passes through the chest wall, costodiaphragmatic recess of the pleura, diaphragm, and right anterior intraperitoneal space to enter the liver. Needle inserted above the 8th intercostal space will injure the lung.
      3. The bare area of the liver is indirect contact with the diaphragm, which separates it from the right pleural cavity. Surgically, it is important because it encloses the right extraperitoneal subphrenic space. In amoebic hepatitis, the pus may collect in this space and form a subphrenic abscess which may burst into the right pleural cavity through the diaphragm.

Theory

  • Put finger in the opening of the inferior vena cava and tilt the liver slightly to hold in an anatomical position.
  • Surfaces-
    • Superior
    • Anterior
    • Posterior
    • Inferior/visceral
    • Right lateral
  • Posterior and inferior surface demarcated by the bare area of the liver-
  • Lobes-
    • Right big
    • Left small
    • In between falciform ligament-
  • Falciform ligament
    • liver develops from mesentery.
    • From gut tube, liver bud develops towards anterior abdominal wall
    • Gut tube is attached to ventral wall by ventral mesentery and to dorsal wall by dorsal mesentery
    • Names of mesentery-
      • Stomach-
        • ventral mesogastrium
          • Liver- anteriorly falciform ligament
          • Liver to stomach – lesser omentum
        • Dorsal mesogastrium
    • Falciform ligament spreads on the liver to form coronary ligament on the right side and triangular ligament on the right side.
    • Superior layer of Coronary ligament goes to right end and then folds back to form the inferior layer of coronary ligament.
  • Bare area of liver-
    • not covered by peritoneum
    •  tightly adhered to diaphragm-
    •  site of a porto caval anastomosis
    • Superior border- superior layer of coronary ligament
    • Inferior border- inferior layer of the coronary ligament
    • Right border – right triangular ligament
    • Left border- opening of IVC
    • Theres another, very small bare area between the two triangular ligaments
  • Ligament teres hepatis.
    • Round ligament of liver
    • Inferior extension of falciform ligament-
    • Connection existing between anterior abdominal wall umbilicus to liver
    • Obliterated part of left umbilical vein
      • Right umbilical vein disappears at end of 2nd month of intrauterine life
      • 2 umbilical arteries develop into Medial Umbilical ligaments on both sides of Uracus
  • Caudate lobe(near IVC)
  • Quadrate lobe below
  • Fossa for gall bladder
  • Ligamentum venosum-
    • Ductus venosus in embryonic life
    • Umbilical vein-> ductus venosus -> IVC -> Heart (bypasses liver in foetal circulation)
    • Fissure for ligamentum venosum
  • Porta Hepatis-
    • Fissure below quadrate lobe and caudate lobe
    • H shaped fissure
    • Gall Bladder-> Cystic Duct + Hepatic Duct -> Bile Duct(doubt)
    • Structures-
      • Anterior and to right- bile duct
      • Anterior and to left- hepatic artery
      • Posteriorly wide open – portal vein
    • Visceral impressions
  • Epiploic foramen-
    • Anterior wall is by structures of porta hepatis
    • Superior boundary is by caudate process
  • Visceral Relations-
    • Left side-
      • Oesophagus
      • Gastric impression for Stomach
      • Tuber omentale- a small elevation where the neck and the body meets
      • 3 impressions-
        • Pylorus
        • Lesser omentum above pylorus
        • Transverse colon below pylorus
      • Right kidney
      • Supra renal gland
  • Blood supply-
    • Main- portal vein
    • Hepatic artery
  • Gall Bladder-
    • Parts-
      • Fundus
        • Fundus lies corresponding to tip of 9th costal cartilage
        • Infection of gall bladder- murphy’s sign can be elicited
      • Bards
      • Neck-
        • Hartman’s pouch- where gall stones are lodged
        • Cystic duct- guarded by Valve of Heister
        • Cystic duct + hepatic duct = Bile Duct (doubt) – opens into D2