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The coeliac trunk (Fig. 12.2)
duodenum and pancreatic head.
This trunk arises from the aorta at the level of T12/L1 and after a short
course divides into three terminal branches. These include the:
• Ileocolic artery: passes in the root of the mesentery over the right
ureter and gonadal vessels to reach the caecum where it divides into ter-
• Left gastric artery: passes upwards to supply the lower oesophagus • Inferior pancreaticoduodenal artery: supplies the lower half of the
by branches which ascend through the oesophageal hiatus in the minal caecal and appendicular branches (Fig. 12.4).
diaphragm. The left gastric then descends in the lesser omentum along • Jejunal and ileal branches: a total of 12–15 branches arise from the
the lesser curve of the stomach which it supplies. left side of the artery. These branches divide and reunite within the
• Splenic artery: passes along the superior border of the pancreas small bowel mesentery to form a series of arcades which then give rise
in the posterior wall of the lesser sac to reach the upper pole of the left to small straight terminal branches which supply the gut wall.
kidney. From here it passes to the hilum of the spleen in the lienorenal • Right colic artery: passes horizontally in the posterior abdominal
ligament. The splenic artery also gives rise to short gastric branches, wall to supply the ascending colon.
which supply the stomach fundus, and a left gastroepiploic branch • Middle colic artery: courses in the transverse mesocolon to supply
which passes in the gastrosplenic ligament to reach and supply the the proximal two-thirds of the transverse colon.
greater curve of the stomach.
• Hepatic artery: descends to the right towards the first part of the The renal arteries
duodenum in the posterior wall of the lesser sac. It then passes between These arise from the abdominal aorta at the level of L2.
the layers of the free border of the lesser omentum which conveys it to
the porta hepatis in close relation to the portal vein and bile duct (these The gonadal arteries (ovarian or testicular)
structures together constitute the anterior margin of the epiploic fora- These arteries arise from below the renal arteries and descend obliquely
men). Before reaching the porta hepatis it divides into right and left on the posterior abdominal wall to reach the ovary in the female, or pass
hepatic arteries and from the right branch the cystic artery is usually through the inguinal canal in the male to reach the testis.
given off. Prior to its ascent towards the porta hepatis the hepatic artery
gives rise to gastroduodenal and right gastric branches. The latter The inferior mesenteric artery (Fig. 12.5)
passes along the lesser curve of the stomach to supply it. The former The inferior mesenteric artery arises from the abdominal aorta at the
passes behind the first part of the duodenum and then branches further level of L3. It passes downwards and to the left and crosses the left
into superior pancreaticoduodenal and right gastroepiploic branches. common iliac artery where it changes its name to the superior rectal
The right gastroepiploic branch runs along the lower part of the greater artery. Its branches include:
curvature to supply the stomach. • The left colic artery: supplies the distal transverse colon, the splenic
flexure and upper descending colon.
The superior mesenteric artery (Fig. 12.3) • Two or three sigmoid branches: pass into the sigmoid mesocolon
The superior mesenteric artery arises from the abdominal aorta at the and supply the lower descending and sigmoid colon.
level of L1. From above downwards, it passes over the left renal vein • The superior rectal artery: passes into the pelvis behind the rectum
behind the neck of the pancreas, over the uncinate process and anterior to form an anastomosis with the middle and inferior rectal arteries. It
to the third part of the duodenum. It then passes obliquely downwards supplies the rectum and upper half of the anal canal.
and towards the right iliac fossa between the layers of the mesentery of The marginal artery (of Drummond) is an anastomosis of the colic
the small intestine where it divides into its terminal branches. The arteries at the margin of the large intestine. This establishes a strong
branches of the superior mesenteric artery include the: collateral circulation throughout the colon.

The arteries of the abdomen 33