800 THE VASCULAR SYSTEM. 4 j 
coehae axis. It runs a more or less tortuous course behind the stomach and the 
lesser sac of the peritoneum, and along the upper border of the pancreas. It hes in 
front of the left suprarenal capsule and the upper end of the left kidney, and 
passes forwards between the two layers of the leno-renal ligament, where it divides 
into from five to eight terminal branches (rami henales), which enter the hilus of the 
spleen and supply the splenic substance. It is accompanied by the splenic vein, 
which les below it. 
Branches.—(i.) Pancreatic (rami pancreatici).— Numerous small branches (pancreatica 
parvee) are given off to the pancreas. One large branch (pancreatica magna), occasionally 
present, enters the upper border of the pancreas, about the junction of its middle and 
left thirds, and runs from left to right in the substance of the pancreas, a little above and 
behind the pancreatic duct. Both the small and large arteries supply the substance of 
the pancreas, and anastomose with one another and with branches of the pancreatico- 
duodenal arteries. 
(ii.) The vasa brevia (aa. gastricxe breves), or short gastric branches, four or five in 
number, are given off either from the end of the main vessel or, more commonly, from 
some of its terminal branches. They pass between the layers of the gastro-splenic 
omentum to the left end of great curvature of the stomach, and anastomose with the 
cesophageal, the gastric, and the left gastro-epiploic arteries. 
(iii.) The left gastro-epiploic branch (a. gastro-epiploica sinistra) arises from the 
front of the splenic, close to its termination, and passes forwards between the layers of the 
gastro-splenic omentum to the left end of the great curvature of the stomach, along which 
it is continued, from left to right, between the layers of the gastro-colic or great omentum. 
It ends by anastomosing w ith the right gastro- epiploic artery, and it gives off numerous 
gastric branches to both surfaces of the stomach, which anastomose with the vasa brevia 
and with branches of the coronary and pyloric arteries. Long slender omental branches 
pass to the omentum and anastomose with branches of the colic arteries. 
(c) The hepatic artery (a. hepatica, Fig. 567) runs along the upper border of 
the head of the pancreas to the right pancreatico-e gastric ‘fold of peritoneum, in 
which it turns forwards to the upper border of the first part of the duodenum. It 
then passes upwards, between the layers of the small omentum, in front of the 
portal vein and to the left of the common bile duct, and reaches the transverse 
fissure of the liver, where it divides into right and left branches. 
Branches. —(i.) The pyloric artery (a. gastrica dextra) is a small branch which 
arises opposite the upper border of the first part of the duodenum. It descends to 
the pylorus, running between the layers of the small omentum, and then turns to the left 
along the smaller curvature of the stomach. It gives branches to both surfaces of the 
stomach, and terminates by anastomosing with the coronar y artery. 
(ii.) The gastro- duodenal artery (a. gastro-duoden: alis). —This branch of the hepatic 
arises Just above the upper border, descends behind, and terminates opposite the lower 
border of the first part of the duodenum. In its course it les between the neck of 
the pancreas and the first part of the duodenum, and it is in front of the portal vein. The 
common bile duct is on its right side. The vessel ends by dividing into the right gastro- 
epiploic and the superior pancreatico-duodenal arteries. The right gastro-epiploic artery 
(a. gastro-epiploica dextra) is the larger of the two terminal branches of the gastro- 
duodenal ; it passes from right to left along the greater curvature of the stomach, between 
the layers of the gastro-colic omentum, and unites with the left gastro-epiploic branch 
of the splenic artery. From the arterial arch so formed branches pass upwards on both 
surfaces of the stomach, and anastomose with branches of the pyloric and coronary arteries. 
Other branches pass downwards to the omentum, and anastomose with branches of the 
colic arteries. The superior pancreatico-duodenal artery (a. pancreatico-duodenalis 
superior) runs a short course to the right, between the duodenum and the head of the 
pancreas, and divides into anterior and posterior terminal branches which descend, the 
former in front of and the latter behind the head of the pancreas, to anastomose with 
similar branches of the inferior pancreatico-duodenal artery. They supply the head 
of the pancreas, anastomosing in it with the pancreatic branches of the splenic artery ; 
branches are also given to the second part of the duodenum and to the common bile duct. 
(iii.) Terminal branches.—The right hepatic artery (ramus dexter) passes either in 
front of or behind the hepatic duct and behind the cystic duct, to the right end of the 
transverse fissure of the liver, where it divides into two or more branches which enter the 
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