Posterior superior pancreaticoduodenal artery

The posterior superior pancreaticoduodenal artery (PSPDA) is a branch of the gastroduodenal artery that arises as the gastroduodenal artery passes behind the first part of the duodenum. It is one of the two superior pancreaticoduodenal arteries (the other being the anterior superior pancreaticoduodenal artery).

Origin and Course

The posterior superior pancreaticoduodenal artery (PSPDA) typically arises from the gastroduodenal artery at the upper border of the first part of the duodenum, before the gastroduodenal artery bifurcates into the right gastroepiploic artery and the anterior superior pancreaticoduodenal artery. It courses posteriorly, descending along the groove between the second part of the duodenum and the head of the pancreas, running behind the common bile duct and the head of the pancreas.

Supply and Anastomosis

• It supplies the posterior aspect of the head of the pancreas via the pancreatic branches of posterior superior pancreaticoduodenal artery and the descending (second) part of the duodenum via the duodenal branches of posterior superior pancreaticoduodenal artery.

• It anastomoses with the posterior inferior pancreaticoduodenal artery, which is a branch of the superior mesenteric artery (SMA). This anastomotic arcade forms a critical connection between the celiac trunk territory (via the gastroduodenal artery) and the SMA territory.

Clinical Significance

• The pancreaticoduodenal arcades (both anterior and posterior) are important collateral pathways. In cases of celiac artery stenosis or occlusion (e.g., from median arcuate ligament syndrome), these arcades can enlarge to provide retrograde flow to the celiac territory via the SMA.

• The PSPDA is a key landmark during pancreaticoduodenectomy (Whipple procedure), where its identification and ligation are essential surgical steps.

• It is also clinically relevant in cases of upper gastrointestinal bleeding, particularly from posterior duodenal ulcers, which may erode into the gastroduodenal artery or its branches, including the PSPDA.

Anatomical Variants

Variations in the origin and branching pattern of the PSPDA are common. In some individuals, the anterior and posterior superior pancreaticoduodenal arteries may arise from a common trunk, or the PSPDA may originate directly from the common hepatic artery or the proper hepatic artery rather than the gastroduodenal artery.