Embryologic and anatomic basis of duodenal surgery

The embryology, congenital anomalies, and surgical anatomy of the duodenum are detailed in this article. Exposure of the duodenum during surgical procedures, surgical applications of the parts of the duodenum, and relations of neighboring anatomic entities also are presented

Embryology, anatomy, and surgical applications of the preperitoneal space

This article discusses the enigmatic preperitoneal space, with emphasis on the spaces of Bogros and Retzius. Detailed information about the anatomic pathway to the preperitoneal space for the repair of inguinofemoral hernia from above (i.e., skin to myopectineal orifice of Fruchaud) and from below (i.e., peritoneum to myopectineal orifice of Fruchaud) is presented

Ultrastructural and immunohistochemical analysis of the 8-20 week human fetal pancreas

Development of the human pancreas is well-known to involve tightly controlled differentiation of pancreatic precursors to mature cells that express endocrine- or exocrine-specific protein products. However, details of human pancreatic development at the ultrastructural level are limited. The present study analyzed 8–20 week fetal age human pancreata using scanning and transmission electron microscopy (TEM), TEM immunogold and double or triple immunofluorescence staining. Primary organization of islets and acini occurred during the developmental period examined. Differentiating endocrine and exocrine cells developed from the ductal tubules and subsequently formed isolated small clusters. Extracellular matrix fibers and proteins accumulated around newly differentiated cells during their migration and cluster formation. Glycogen expression was robust in ductal cells of the pancreas from 8–15 weeks of fetal age; however, this became markedly reduced at 20 weeks, with a concomitant increase in acinar cell glycogen content. Insulin secretory granules transformed from being dense and round at 8 weeks to distinct geometric (multilobular, crystalline) structures by 14–20 weeks. Initially many of the differentiating endocrine cells were multihormonal and contained polyhormonal granules; by 20 weeks, monohormonal cells were in the majority. Interestingly, certain secretory granules in the early human fetal pancreatic cells showed positivity for both exocrine (amylase) and endocrine proteins. This combined ultrastructural and immunohistochemical study showed that, during early developmental stages, the human pancreas contains differentiating epithelial cells that associate closely with the extracellular matrix, have dynamic glycogen expression patterns and contain polyhormonal as well as mixed endocrine/exocrine granules

Pancreatographic investigation of pancreatic duct system and pancreaticobiliary malformation

To clarify the anatomy of the pancreatic duct system and to investigate its embryology, we reviewed 256 pancreatograms with normal pancreatic head, 81 with pancreas divisum and 74 with pancreaticobiliary maljunction. Accessory pancreatograms were divided into two patterns. The long-type accessory pancreatic duct forms a straight line and joins the main pancreatic duct at the neck portion of the pancreas. The short-type accessory pancreatic duct joins the main pancreatic duct near its first inferior branch. The short-type accessory pancreatic duct is less likely to have a long inferior branch arising from the accessory pancreatic duct. The length of the accessory pancreatic duct from the orifice to the first long inferior branch was similar in the short- and long-type accessory pancreatic ducts. The first long inferior branch from the long-type accessory pancreatic duct passes though the main pancreatic duct near the origin of the inferior branch from the main pancreatic duct. Immunohistochemically, in the short-type accessory pancreatic duct, the main pancreatic duct between the junction with the short-type accessory pancreatic duct and the neck portion was located in the ventral pancreas. The long-type accessory pancreatic duct represents a continuation of the main duct of the dorsal pancreatic bud. The short-type accessory pancreatic duct is probably formed by the proximal main duct of the dorsal pancreatic bud and its long inferior branch