Duodenum

1. Dr. Mujahid Khan

2.  It is a “C” shaped tube
 About 10 inches (25 cm) long
 It joins the stomach to the jejunum
 It receives openings of bile and pancreatic
ducts
 Curves around the head of the pancreas

4.  First inch of duodenum resembles stomach as
its anterior and posterior surfaces are also
covered with peritoneum
 Lesser omentum attached to its upper border
 Greater omentum attached to its lower border
 Remainder of the duodenum is retroperitoneal,
only partially covered by peritoneum
 Is divided into four parts for the purpose of
description

6.  It is 2 inches (5 cm) long and begins at pylorus
 Situated in the epigastric and umbilical regions
 Lies on the transpyloric plane

7.  Anteriorly: Quadrate lobe of the liver and gall
bladder
 Posteriorly: The lesser sac, gastroduodenal
artery, bile duct, portal vein and IVC
 Superiorly: The entrance into the lesser sac
 Inferiorly: Head of the pancreas

8.  Is 3 inches (8 cm) long and runs vertically
downward in front of the hilum of the right
kidney
 Halfway down its medial border, the bile duct
and main pancreatic duct pierce the duodenal
wall by major duodenal papilla
 The accessory pancreatic duct if present, opens
a little higher up on the minor duodenal papilla

10.  Anteriorly: The fundus of gall bladder, right
lobe of liver, and the transverse colon
 Posteriorly: Hilum of the right kidney and the
right ureter
 Laterally: Ascending colon, right colic flexure,
and the right lobe of the liver
 Medially: Head of the pancreas, bile duct, and
the main pancreatic duct

11.  Is 3 inches (8 cm) long
 Runs horizontally to the left on the subcostal
plane
 Passing in front of the vertebral column
 Following the lower margin of the head of the
pancreas

12.  Anteriorly: The root of mesentery of small
intestine, superior mesenteric vessels
 Posteriorly: The right ureter, right psoas
muscle, IVC, and the aorta
 Superiorly: Head of the pancreas
 Inferiorly: Coils of jejunum

13.  Is 2 inches (5 cm) long
 Runs upward and to the left of the
duodenojejunal flexure
 The flexure is held in position by a peritoneal
fold, ligamentum treitz

14.  Anteriorly: The beginning of the root of the
mesentery and coils of jejunum
 Posteriorly: The left margin of aorta, and the
medial border of the left psoas muscle

15.  Is thick and smooth in the first part
 In the remainder parts is thrown into
numerous circular folds called plicae circulares

17.  The upper half is supplied by superior
pancreaticoduodenal artery, a branch of
gastroduodenal artery
 The lower half is supplied by the inferior
pancreaticoduodenal artery, a branch of the
superior mesenteric artery

18.  The pancreas is both an exocrine and an
endocrine gland
 Produces a secretion that hydrolyzes the
carbohydrates, proteins and fats
 The endocrine portion of the gland is islets of
langerhans produces insulin and glucagon
hormones
 These hormones play a key role in
carbohydrate metabolism

19.  It is an elongated structure
 Lies in the epigastrium and left upper quadrant
 It is soft and lobulated, situated on the
posterior abdominal wall behind the
peritoneum
 It is divided into head, neck, body and tail

21.  Head: Is a disc shaped and lies within the
concavity of the duodenum, has a process
behind the superior mesenteric vessels called
uncinate process
 Neck: Is the constricted portion, connects the
head to the body, lies in front of the origin of
the superior mesenteric artery from the aorta

23.  Body: Runs upward and to the left across the
midline and is somewhat triangular in cross
section
 Tail: Passes forward in the splenicorenal
ligament and comes in contact with the hilum
of the spleen

24.  Anteriorly: Transverse colon and the
attachment of the transverse mesocolon, the
lesser sac and the stomach
 Posteriorly: Bile duct, the portal and splenic
veins, IVC, the aorta, the origin of superior
mesenteric artery, the left suprarenal gland, the
left kidney, and the hilum of the spleen

25.  The main duct of the pancreas begins in the tail
 Runs the length of the gland, receiving
numerous tributaries
 Opens into the second part of the duodenum
with the bile duct on the major duodenal
papilla

27.  Sometimes the main duct drains separately into
the duodenum
 The accessory duct, if present, drains the upper
part of the head
 Opens a little above the main duct on the
minor duodenal papilla
 The accessory duct frequently communicates
with the main duct

29.  Arteries: The superior and inferior
pancreaticoduodenal arteries
 Veins: The corresponding veins drain into the
portal vein