Exposure of the Superior Mesenteric Artery and Celiac Axis
Surgical Anatomy
The celiac axis refers to a short arterial trunk originating from the anterior surface of the proximal abdominal aorta as it passes between the diaphragmatic crura at the level of the 12th thoracic vertebra (T12). The artery divides most often into three major branches within 2 cm of its origin: the common hepatic, splenic, and left gastric arteries (Fig. 34-1, A and B). These arterial branches and their tributaries provide the blood supply for the stomach, liver, spleen, portions of the pancreas, and proximal duodenum. The common hepatic artery gives rise to the superior pancreaticoduodenal arteries, cystic artery, and right gastric artery in addition to its left and right hepatic arteries. In approximately 18% of cases, the right hepatic artery is “replaced” and originates from the superior mesenteric artery. The splenic artery gives off the dorsal pancreatic artery, left gastroepiploic artery, and short gastric arteries before completing its tortuous course toward the spleen. The left gastric artery supplies the gastric cardia and fundus before anastomosing with the right gastric artery. A “replaced” left hepatic artery originates from the left gastric artery in approximately 12% of cases.
FIGURE 34–1 Celiac axis and superior mesenteric artery (SMA). (D from Horton KM, Fishman EK. Multidetector CT angiography in the diagnosis of mesenteric ischemia. Radiol Clin North Am 2007;45:275-88.)