ANATOMY OF THE DUODENUM, PANCREAS, SPLEEN AND PORTAL VEIN Flashcards
Where is the infracolic compartment?
lies beneath the transverse colon
Describe the lesser sac
recess of peritoneal cavity that lies posterior to the stomach
Where is the spleen located?
under cover of the diaphragm and ribcage
o Main surface lies against the diaphragm
o Obscured by the stomach
Describe the structure of the spleen
The spleen has a slightlyovalshape.
covered by a weak capsule that protects the organ, whilst allowing it to
expand in size.
The outer surface can be anatomically divided into two:
o Diaphragmatic surface– in contact with diaphragm and ribcage.
o Visceral surface– in contact with the other abdominal viscera.
It has anterior, superior, posteromedial and inferior borders.
The posteromedial and inferior borders are smooth, whilst the anterior and superior borders
containnotches.
What is the arterial supply of the spleen
Receives its arterial supply from the splenic artery.
o arises from the coeliac trunk
o Runs laterally along the superior aspect of the pancreas, within the splenorenal ligament.
o torturous vessel – may be to even off the pulsations so that the spleen does not pulsate
Evens out pulse pressures for a more continuous flow of blood
o As the artery reaches the spleen, it branches into five vessels – each supplying a different part of
the organ.
o branches do not anastomose with each other – gives rise to vascular segments of the spleen.
o Possible to remove one of these segments without affecting the others (subtotal splenectomy).
What is the venous drainage of the spleen
Venous drainage occurs through the splenic vein.
o Several veins exit the spleen at the hilum of the spleen
o Splenic vein runs posterior to the body of the pancreas
o Joins with the superior mesenteric vein to form the portal vein
o Portal vein runs up towards the liver and splits into left and
right branches
What is the innervation of the spleen
The nerve supply to the spleen is from the coeliac plexus
Describe the head of the pancreas
Head: This is the widest part of the pancreas.
o Lies within the C-shaped curve created by the duodenum,
o Attached to the medial aspect of descending duodenum and horizontal parts by connective
tissue.
o Bile duct lies on a groove on its posterior side
Describe the uncinate process of the pancreas
Uncinate process: projection arising from the lower part of the head and extending medially to lie
beneath the body of the pancreas.
o Lies posterior to the superior mesenteric vessels.
o Uncus – latin for ‘hook’
Describe the neck of the pancreas
Neck: Located between the head and the body of the pancreas.
o Anterior surface covered with peritoneum
o Part of pancreas that lies in front of the formation of the portal vein
Describe the body of the spleen
Body: centrally located, crossing the midline of the human body
o Lies behind the stomach and to the left of the superior mesenteric vessels.
o Anterior surface covered with peritoneum
Describe the tail of the spleen
Tail: left end of the pancreas that lies within close proximity to the hilum of the spleen.
o Contained within the splenorenal ligament with the splenic vessels.
o Only part of the pancreas that is intraperitoneal.
o Relatively mobile
Describe the blood supply of the pancreas
supplied by the pancreatic branches of the splenic artery.
The head is additionally supplied by:
o Superior pancreaticoduodenal artery -
branch of the gastroduodenal artery (from coeliac trunk)
o Inferior pancreaticoduodenal artery branch of the superior mesenteric artery
What is the venous drainage of the pancreas
Venous drainage:
o head - superior mesenteric vein.
Rest of the pancreas - pancreatic veins (drain
into the splenic vein)
