Definition of Annular pancreas:

An annular pancreas is a ring of pancreatic tissue that encircles the duodenum (the first part of the small intestine, just below the stomach).

Causes, incidence, and risk factors:

Annular pancreas is caused by malformation during the development of the pancreas, before birth. This condition may result in a narrowing of the duodenum due to squeezing by the ring of pancreas.

Complete obstruction of the duodenum is often seen in newborns with this condition. However, half of cases are not diagnosed until symptoms occur in adulthood. There are probably many cases that go undetected due to mild symptoms.

People with this condition are more like to have a peptic ulcer.