Establishment of the Guideline for the Anatomical Resection of the Ventral and Dorsal Portion of the Pancreatic Head

ABSTRACT

PURPOSE: This study was designed to delineate the anatomical details of the pancreatic head for a ventral or dorsal segmental pancreatic resection along the embryological fusion plane, and to determine the feasibility of both procedures. METHODS: The resected pancreaticoduodenectomy specimens were analyzed (n=8), with the pancreatic and distal common bile ducts visualized by pancreatography (n=8). Immunohistochemical staining, with pancreatic polypeptide (PP), was performed in serially sliced specimens (n=3). The immunohistochemical and H&E staining were performed to evaluate the composition of the anatomical structures of the two differentially stained pancreas. RESULTS: What was presumed to be the embryological fusion plane was discovered between two differentially stained segments. This started just above the anterior inferior pancreaticoduodenal artery, directed to the posterior superior part of the pancreatic head and ended at the anterior surface of the distal common bile duct. The duct of Wirsung and the distal common bile duct were included in the posterior segment of the pancreas (ventral pancreas). There were two types of pancreatic duct arrangement, with the differences between the two types being; (1) the distance between the fusion point of the ventral and dorsal pancreatic ducts and the papilla of Vater, and (2) the stream of the Santorini duct. The branches of the pancreatic ducts were scattered over the entire pancreatic head region in multiple-directions. CONCLUSION: The fusion plane of the ventral and dorsal pancreas seems to initiate just above the anterior inferior pancreaticoduodenal artery, in a posterior-superior direction along the anterior surface of the distal common bile duct. A ventral pancreatectomy seems an impractical procedure with regard to the postoperative morbidity and operative difficulty, while a dorsal pancreatectomy seems to be more practical and feasible in its clinical aspects.