Pancreas divisum literally means "divided pancreas". In early life the pancreas consists of two small 'buds' arising from the primitive foregut. One is located in front (called ventral), the other one in the back (called dorsal). At the end of the 6th week of pregnancy, however, these two buds have rotated in such a way that they are close together and can fuse

The dorsal bud and its ducts (drainage tubes) form the body, tail and part of the head of the pancreas. The ventral bud completes the head and a part of the pancreas known as the uncinate process. The ducts fuse forming a main and an accessory pancreatic duct.

If the fusion of the dorsal bud and ventral bud does not happen, the pancreas ducts are disconnected, a condition known as 'pancreas divisum'

This is actually not unusual and occurs in 5 - 10 % of normal people. However, in patients with unexplained chronic pancreatitis, pancreas divisum is found much more frequently. Also, there are a number of patients where recurrent acute pancreatitis seems to be related to the presence of pancreas divisum.

Sometimes the drainage from the dorsal duct is impaired because the pancreatic juice has to flow through a smaller opening (the minor papilla). If this seems to be the problem, endoscopic therapy during ERCP may help.

Pancreas divisum is the most common variant of human pancreas, occurring in nearly 10% of the population. This anomaly results from the failure of fusion of the dorsal and ventral pancreatic ducts, which usually occurs in the second month of fetal life. This results in the drainage of the main pancreatic duct (including the superior-anterior aspect of the head, the body and the tail) into the dorsal duct via the accessory papilla. The ventral duct, which drains the posterior-inferior aspect, joins the common bile duct and empties into the major papilla . The diagnosis of this condition is made by ERCP.

Most patients having this anomaly are symptom-free, although some reports have suggested a high incidence of abdominal pain and pancreatitis. It has been suggested that the relative stenosis of the accessory papillary orifice, the major outflow tract for pancreatic secretions, is the cause of problems.

Endoscopic sphincterotomy or transduodenal sphincteroplasty has been advocated as the operation of choice in these individuals. The results obtained with this intervention have been controversial. Some studies have reported a success rate of 90% in patients with pancreas divisum pancreatitis after two years, whereas other reports did not support such findings. From the available literature, surgical intervention in pancreas divisum is as controversial as its causative relationship in abdominal pain and pancreatitis.