1. Understand the concepts & associated principles, functional & clinical
applications of: Liver; gall bladder; bile duct; pancreas.
Liver
Surfaces
 The diaphragmatic is smooth, domed and lies against the inferior surface of the
diaphragm
 The visceral surface in the inferior direction border follows the contour of the
right costal margin. When the liver is enlarged the lower border becomes palpable
below the costal margin.
Lobes & Fissures
The liver anatomically consists of a large right lobe, and a smaller left lobe. These are
separated antero-superiorly by the falciform ligament and postero-inferiorly by fissures
for the ligamentum venosum and ligamentum teres. In the anatomical classification the
right lobe includes the caudate and quadrate lobes. Functionally, however, the caudate
and most of the quadrate lobes are units of the left lobe as they receive their blood
supplies from the left hepatic artery and deliver their bile into the left hepatic duct.
Hence, the functional classification of the liver defines the right and left lobes as
separated by fossae for the gallbladder and the inferior vena cava
 the quadrate lobe is visible on the upper part of the visceral surface of the liver
and is bounded on the left by the fissure for ligamentum teres and on the right by
the fossa for the gallbladder.
 the caudate lobe is visible on the lower part of the visceral surface of the liver
and is bounded on the left by the fissure for the ligamentum venosum and on the
right by the groove for the inferior vena cava.
Porta Hepatis
The porta hepatis serves as the point of entry into the liver for the hepatic arteries and the
portal vein, and the exit point for the hepatic ducts
Hepatic Ducts: Right and Left & Common
The common hepatic duct is the combination of the right and left hepatic ducts in the
porta hepatis. This structure courses, sequentially, in the free edge of the lesser omentum,
behind the first part of the duodenum and in the groove between the second part of the
duodenum and the head of the pancreas. It ultimately opens at the papilla on the medial
aspect of the second part of the duodenum.
Peritoneal attachments & Bare area
The liver is attached to the anterior abdominal wall by the falciform ligament and,
except for a small area of the liver against the diaphragm (the bare area), the liver is
almost completely surrounded by visceral peritoneum. Additional folds of peritoneum
connect the liver to the stomach (hepatogastric ligament), the duodenum
(hepatoduodenal ligament), and the diaphragm (right and left triangular ligaments
and anterior and posterior coronary ligaments).
Blood Vessels
The liver is made up of multiple functional units called lobules. Branches of the portal
vein and hepatic artery transport blood through portal canals into a central vein by way of
sinusoids which traverse the lobules. The central veins ultimately coalesce into the right,
left and central hepatic veins which drain blood from corresponding liver areas
backwards into the IVC. The extensive length of gut that is drained by the portal vein
explains the predisposition for intestinal tumours to metastasize to the liver.
Bile Production in the Bile Canaliculi within the Lobules
The portal canals also contain tributaries of the hepatic ducts which serve to drain bile
from the lobule down the biliary tree from where it can be concentrated in the gallbladder and eventually released into the duodenum.
Gall bladder
The gall-bladder lies adherent to the Visceral (undersurface) of the liver in the
transpyloric plane at the junction of the right and quadrate lobes. The duodenum and the
transverse colon are behind it. The gall-bladder acts as a reservoir for bile which it
concentrates. It usually contains approximately 50 mL of bile which is released through
the cystic and then common bile ducts into the duodenum in response to gall-bladder
contraction induced by gut hormones.
• Structure: the gall-bladder comprises a fundus, a body and a neck (which opens into
the cystic duct).
• Blood supply: the arterial supply to the gall-bladder is derived from two sources: the
cystic artery which is usually, but not always, a branch of the right hepatic artery, and
small branches of the hepatic arteries which pass via the fossa in which the gall-bladder
lies. The cystic artery represents the most significant source of arterial supply. There is,
however, no corresponding cystic vein but venous drainage occurs via small veins
passing through the gall-bladder bed.
Bile Duct
The common hepatic duct is joined by the cystic duct to form the common bile duct. The
common bile duct usually, but not always, joins with the main pancreatic duct
Pancreas
The pancreas has a: head, neck, body and tail. It is a retroperitoneal organ which lies
roughly along the transpyloric plane. The head is bound laterally by the curved
duodenum and the tail extends to the hilum of the spleen in the lienorenal ligament. The
superior mesenteric vessels pass behind the pancreas, then anteriorly, over the uncinate
process and third part of the duodenum into the root of the small bowel mesentery. The
inferior vena cava, aorta, coeliac plexus, left kidney (and its vessels) and the left adrenal
gland are posterior pancreatic relations. In addition, the portal vein is formed behind the
pancreatic neck by the confluence of the splenic and superior mesenteric veins. The
lesser sac and stomach are anterior pancreatic relations.
• Structure: The pancreatic duct begins in the tail of the pancreas. It passes to the right
through the body of the pancreas and, after entering the head of the pancreas, turns
inferiorly. In the lower part of the head of pancreas, the pancreatic duct joins the bile
duct. The joining of these two structures forms the hepatopancreatic ampulla (ampulla
of Vater), which enters the descending part of the duodenum at the major duodenal
papilla. Surrounding the ampulla is the sphincter of ampulla (sphincter of Oddi), which
is a collection of smooth muscle.
• Blood supply: the pancreatic head receives its supply from the superior and inferior
pancreaticoduodenal arteries. The splenic artery courses along the upper border of the
body of the pancreas which it supplies by means of a large branchathe arteria
pancreatica magnaa and numerous smaller branches.
• Function: the pancreas is a lobulated structure which performs both exocrine and
endocrine functions. The exocrine secretory glands drain pancreatic juice into the
pancreatic ducts and, from there, ultimately into the duodenum. The secretion is essential
for the digestion and absorption of proteins, fats and carbohydrates. The endocrine
pancreas is responsible for the production and secretion of glucagon and insulin, which
take place in specialized cells of the islets of Langerhans.
Exocrine Glands: A gland that secretes its products through a duct to the surface of the body or of an
organ. The sweat glands in the skin and the salivary glands in the mouth are examples. The secretion is set
off by a hormone (see HORMONES) or a NEUROTRANSMITTER.
Endocrine Glands: Organs whose function it is to secrete into the blood or lymph, substances known as
HORMONES. These play an important part in general changes to or the activities of other organs at a
distance. Various diseases arise as the result of defects or excess in the internal secretions of the different
glands.