The Puestow procedure is a lateral side-to-side pancreaticojejunostomy that is used for the treatment of chronic pancreatitis. The pancreas is essentially filleted along its long axis from the uncinate process to the tail and connected to a Roux en-Y loop of jejunum.
The pancreaticojejunal anastomosis can usually be seen on CT. The anastomosed loop of bowel may be collapsed and empty, creating a soft tissue bulge arising from the anterior aspect of the pancreatic body and/or tail. This may be mistaken for a tumour when collapsed, or an abscess or pseudocyst when full of fluid and/or gas.
The anastomosed loop of bowel may also contain small amounts of fluid or gas, mimicking an abscess, or be filled with refluxed enteric contrast. If the afferent jejunal loop is collapsed, the anastomosis may not be clearly seen.
Peripancreatic stranding may occur around the anastomosis which may be difficult to differentiate from a recurrent pancreatitis. Pancreatic calcifications, gas, or enteric contrast may enter the pancreatic duct. Some patients who also have a choledochoduodenostomy, choledochojejunostomy, hepaticoduodenostomy, or hepaticojejunostomy before or during the Puestow procedure may also demonstrate pneumobilia.