If the pancreatic duct is dilated and symptoms persist, a longitudinal pancreaticojejunostomy (Puestow) is performed (Figure below). In this operation, the pancreatic duct is slit open and anastomosed side-to-side to the cut end of the divided jejunum with a Roux-en-Y anastomosis. Resection of the pancreas is reserved for patients without a dilated duct (<6 mm). In these cases, a distal pancreatectomy is performed when the disease primarily involves the body and tail of the pancreas; whereas, a Whipple operation is performed when the disease is confined to the head.Lateral pancreatic jejunostomy (Puestow) for chronic pancreatitus