Anatomy of the pancreas and the spleen

The pancreas comprises a head, uncinate process, neck, body and tail. It lies retroperitoneally, roughly at the transpyloric plane, separated from the stomach in front by the lesser sac. Its tail abuts onto the spleen. It has a rich blood supply, from the superior and inferior pancreatico-duodenal arteries and, particularly, from the tortuous splenic artery, which lies along its superior border. Its corresponding veins drain into the portal system. It has both exocrine (digestive enzymes), and endocrine secretory functions, the latter, most importantly, being the secretion of insulin from the islet cells. It also secretes glucagon, somatostatin and gastrin.The spleen fits comfortably into the palm of the hand. It is just palpable when it is enlarged to three times normal size. It lies against the left diaphragm, which separates it from the base of the left lung and the ninth, 10th and 11th ribs. It is supplied at its hilum by the splenic artery and vein. It has a thin, closely adherent capsule which provides trabeculae which divide the contained vascular splenic pulp.Aberrant splenic tissue may occur, especially at the splenic hilum.