The arterial blood supply of the pancreas: a review. IV. The anterior inferior and posterior pancreaticoduodenal aa., and minor sources of blood supply for the head of the pancreas. An anatomical review and radiologic study.

The present article is the fourth part of a comprehensive review of the arterial blood supply of the pancreas and completes the study of the arterial vascularization of the pancreatic head dealing with the anterior inferior and posterior inferior pancreaticoduodenal aa. and with some minor sources of blood supply not involving the classical system of the pancreaticoduodenal arches. The aim of this review is to summarise the anatomical studies, starting from Haller's reports, and to supply, as far as possible with original material, angiographic evidence for the classic anatomical concepts. For this purpose, 1015 selective angiographs (celiac trunk and its branches, superior mesenteric a.) were taken from the angiographic archives of the Institutes of Radiology of Siena, Rome (Catholic University), and Perugia. These demonstrated the anterior inferior pancreaticoduodenal a., present in most instances, as arising from the inferior pancreaticoduodenal a., from a common trunk with the posterior inferior pancreaticoduodenal a. and the 1st jejunal a., from the 1st jejunal a. or from the superior mesenteric a.; on the other hand, the posterior inferior pancreaticoduodenal a. was more variable, originating from the inferior pancreaticoduodenal a., from a common trunk with the anterior inferior pancreaticoduodenal a. and the 1st jejunal a., from the superior mesenteric a., from the dorsal pancreatic a., or from a right accessory hepatic a. coming from the superior mesenteric a. In addition, minor branches to the head of the pancreas arose from the gastroduodenal a., the dorsal pancreatic a., the common hepatic a. and the inferior right phrenic a. Other origins of the inferior pancreaticoduodenal aa. previously reported, but not angiographically detectable with certainty, as well as further minor sources of blood supply to the head of the pancreas, have been listed. The differing opinions regarding the incidence of the various ways the inferior pancreaticoduodenal aa. arise are discussed and an attempt is made to explain the variability of the vascular anatomy of the pancreatic head on embryologic grounds.