ABSTRACT
For a better understanding of the vascular diseases of the liver, a concise review of the vascular anatomy of the liver is important.
ANATOMY OF THE SPLANCHNIC CIRCULATION The splanchnic circulation comprises the arterial blood supply and venous drainage of the entire gastrointestinal tract from the distal esophagus to the mid rectum and includes the spleen, pancreas, gallbladder, and liver. The arterial system is derived from the celiac artery and the superior and inferior mesenteric arteries. The superior mesenteric artery arises from the abdominal aorta just distal to the celiac trunk. For most of its course, this artery lies in the mesentery, with the ileocolic artery being the terminal branch. The superior mesenteric artery gives off three sets of branches: 1) several small branches to the pancreas and duodenum before entering the mesentery, 2) three large arteries that supply the proximal two-thirds of the large bowel, and 3) during its course through the mesenteric root, an arcade of arterial branches to supply the jejunum and ileum. The branches given off in the mesentery form a row of arterial arcades that terminate in the arteriae rectae of the wall of the small bowel. The venous drainage has a similar pattern, with the venae rectae forming a venous arcade that drains the small bowel. These join with the ileocolic, middle colic, and right colic veins to form the superior mesenteric vein.
