opening of the common bile duct into main pancreatic duct is controlled by sphincter of Boyden. The accessory pancreatic duct opens into duodenum with separate openings located above the opening of the main pancreatic duct. Parts The head of the pancreas sits within the curvature of the duodenum, and wraps around the superior mesenteric artery and vein. To the right sits the descending part of the duodenum, and between these travel the superior and inferior pancreaticoduodenal arteries. Behind rests the inferior vena cava, and the common bile duct. In front sits the peritoneal membrane and the transverse colon. A small uncinate process emerges from below the head, situated behind the superior mesenteric vein and sometimes artery. The neck of the pancreas separates the head of the pancreas, located in the curvature of the duodenum, from the body. The neck is about wide, and sits in front of where the portal vein is formed. The neck lies mostly behind the pylorus of the stomach, and is covered with peritoneum. The anterior superior pancreaticoduodenal artery travels in front of the neck of the pancreas. The body is the largest part of the pancreas, and mostly lies behind the stomach, tapering along its length. The peritoneum sits on top of the body of the pancreas, and the transverse colon in front of the peritoneum. Behind the pancreas are several blood vessels, including the aorta, the splenic vein, and the left renal vein, as well as the beginning of the superior mesenteric artery. Below the body of the pancreas sits some of the small intestine, specifically the last part of the duodenum and the jejunum to which it connects, as well as the suspensory ligament of the duodenum which falls between these two. In front of the pancreas sits the transverse colon. The pancreas narrows towards the tail, which sits near to the spleen. It is usually between long, and sits between the layers of the ligament between the spleen and the left kidney. The splenic artery and vein, which also passes behind the body of the pancreas, pass behind the tail of the pancreas. Blood supply The pancreas has a rich blood supply, with vessels originating as branches of both the coeliac artery and superior mesenteric artery. The splenic artery runs along the top of the pancreas, and supplies the left part of the body and the tail of the pancreas through its