Download Learning Objectives of Duodenum and Pancrease

Pancreas and duodenum gross anatomy by dr santosh
It is shortest (25cm), widest and most fixed part of small intestine which is devoid of mesentery but
partly covered with peritoneum.
It is just like a constant curve which encloses the head of pancreas.
It starts at pylorus, passes upward and backward undercover of posterior part of quadrate lobe of liver.
It forms a curve i.e.
superior duodenal flexure and comes downward about 7.5cm infront of medial part of right kidney at
the level of 4LV.
From the here it makes a 2nd curve
Inferior duodenal flexure i.e. right to left of the vertebral column just above the umbilicus
.
. Then again ascends up in front and left of abdominal aorta 2.5cm at the level of 2LV and joins with the
jujenum forming the
duodenojejunal flexure.
Superior part (1st part):
Most moveable part and 5cm in length starts – at pylorus Ends – Neck of gallbladder covered with
peritoneum anteriorly, devoid of peritoneum posteriorly except at the area of pylorus where it takes the
part in formation of omental bursa (Lesser sac).
Anterior:
Quadrate lobe of liver and gallbaldder.
Posterior:
Gastroduodenal artery and portal vein and bile duct.
Superior:
Epiploic foramen.
Inferior:
Head of pancreas.
Descending part (2nd part):
8cm in its length starts at the neck of gallbladder (superior duodenal flexure)
end lower border of 3LV.
It descends along the right side of vertebral column
Crossed by Tr. Colon. The parts above and below the transverse colon are covered with peritoneum.
Anterior – Right lobe of liver, Tr. Colon, Tr. Mesocolon (root) and jujenum.
Posterior – Hilus of right kidney, renal vessels, inferior vena cava.
Medial – Head of pancreas, bile duct and pancreatic duct.
Lateral – Right colic flexure.
Both (bile and pancreatic) ducts enter in the wall of duodenum obliquely and they unite to form short
dilated duct known as hepatopancreatic ampulla which opens in major duodenal papilla i.e. papilla of
vater (ampulla of vater).
Some times accessory pancreatic duct opens in minor papilla which is situated 2cm proximal to major
duodenal papilla
Horizontal (3rd part) (inferior part)
10cm long starts at the right side of 3LV (inferior duodenal flexure). Ends – Infront of aorta in its 4th part.
It is retroperitoneal i.e. only anterior surface is covered with peritoneum except the median plane
where it is crossed by superior mesenteric vessels and root of mesentery.
Anterior – Root of mesentery of small intestine and superior mesenteric vessels.
Posterior surface is covered by the peritoneum only at its left end where the left layer of mesentry
sometimes cover it.
This surface rest on R.ureter, R.psoas muscle, R. testicular or ovarian vessels, inferior vena cava and
abdominal aorta.
Superior – Head of pancreas.
Inferior – Coils of jujenum.
Ascending (4th part):
2.5cm long, ascends to the left of aorta and ends at 2LV as Duodenojujenal junction which is fixed by a
fibromuscular band ligament of treitz or suspensory ligament of duodenum of duodenum (muscle)
which arises from the right crus of diaphragm.
Anterior – Transverse colon and Tr.mesocolon.
Posterior – Left psoas muscle and left sympathetic trunk, left renal and left testicular / ovarian vessels.
Superior – Head of pancreas.
Left – Left kidney with ureter.
Right – Root of mesentery.
Blood supply:
From the arteries of foregut as well as mid gut.
1. Right gastric artery – Hepatic artery, - colic trunk – Abdominal aorta.
2.
Supra duodenal artery – gastroduodenal or hepatic even from right gastric artery – coelic – A.A.
(Superior aspect of upper parts of anterior and posterior surfaces of proximal ½ of duodenum.
3. Right gastroepipolic – Terminal branch of gastroduodenal – hepatic – coelic – A.A (Lower
surface of superior part of duodenum).
4. Superior pancreaticoduodenal – hepatic – coelic – Abdominal aorta.
5. Inferior pancreaticoduodenal – superior mesenteric artery of abdominal aorta.
Veins: Splenic, superior mesentric, portal veins
.
Lymph nodes: Duodenum – pancreaticoduodenal, coelic and superior mesentric nodes – hepatic nodes.
Nerve supply: Coelic plexus (parasympathetically) T9 – T10 (sympathetically).
Clinical anatomy – ulcer, diverticula, stenosis and obstruction.
PANCREAS
There are two embryological primordia of the pancreas.
Ventral bud → Head and uncinate process
Dorsal bud → Remaining part
This is soft lobulated, greyish pink gland partly exocrine (pancreatic acini) and partly endocrine
(pancreatic islets) (insulin and glucogan) 12 – 15cm long lying behind the stomach.
It lies more or less transversally on the posterior abdominal wall at L1 + L2 level weighing almost about
20gms.
It has head, neck body and tail.
Head:
It lies in the curve of duodenum over the inferior nerve care and right and left renal veins.
From the lower and left part of head there is a prolongation, known as uncinate process which is closely
related with bile duct, it is anterior to superior mesenteric vessels and posterior to aorta.
Head has superior, inferior and right lateral borders. Anterior and posterior surface.
Superior border → 1st part of duodenum and superior pancreatico duodenal artery.
Lateral border → 2nd part of duodenum + terminal part of bile duct and anastomosis between P.D
arteries.
Inferior border → 3rd part of duodenum and inferior P.D artery.
Anterior surface → on the right side there is a groove for gastroduodenal artery. Where as on the left
side superior mesenteric and splenic veins join together to form portal vein.
Below and right of neck anterior surface is also related to transverse colon – transverse mesocolon and
coils of jejunum.
Posterior surface → related to inferior vena cava, terminal parts of renal veins, right crus of diaphragm
and bile duct.
Neck:
This is a constricted portion between the head and body.
Anterior → to lesser sac of peritoneum and pylorus. At its junction with head gastroduodenal and
superior pancreaticoduodenal artery lies.
Posterior → This surface is related to the termination of superior mesenteric vein and start of portal
vein.
Body:
This is triangular in shape.
Tuber omentale → Projection of body beyond the superior border.
Anterior border → gives attachment for the root of transverse mesocolon.
Superior border → Coelic artery, hepatic A, splenic artery.
Inferior border → related to superior mesentric vessels.
Anterior surface → Concave, covered with peritoneum and is related to lesser sac and stomach.
Posterior surface → Devoid of peritoneum, related to aorta, left crus of diaphragm, left supra renal
gland, left kidney, left renal vessels and splenic vein.
Inferior surface → Covered with peritoneum and is related to duodenojejunal flexure, coils of jejunum
and left colic flexure.
Tail:
This is long, narrow left extension of pancreas.
It is in contact with gastric surface of spleen.
It lies in lienorenal ligament with splenic vessels.
Main pancreatic duct (Wirsung):
Airse from tail runs towards right through the body, neck and head and is related to bile duct.
The two ducts enter in the wall of 2nd part of duodenum and join to form the ampulla of vater and opens
in major duodenal papilla.
Accessory pancreatic duct (santorini):
Drain the uncinate process and opens into the minor duodenal papilla.
Arteries:
1. Pancreatic branch of splenic artery (dorsal branch of splenic A. Arteria pancreatica
magna)
2. Superior pancreatic duodenal artery arises from common hepatic artery which arises
from coelic trunk.
3.
Inferior pancreaticoduodenal artery → superior mesenteric artery.
Lympatic drainage → Splenic, coelic and superior mesenteric group of lymph nodes.
Nerves: Sympathetic by → splanchnic nerves.
Parasympathetic → controls pancreatic secretions.