Think of the gallbladder as a small storage facility for bile, which is originally produced by the liver. The gallbladder releases bile into the common bile duct, which runs to the small intestine and along the way picks up digestive juices from the intersecting pancreatic duct. After that point, bile and pancreatic juice continue to flow together to the small intestine, where they play key roles in the digestive process.
Yet things can go wrong when small gallstones form in the gallbladder – typically from excess cholesterol or other waste – and pass into the common bile duct. Gallstone pancreatitis occurs when those gallstones block off the pancreatic duct downstream. This typically causes acute pancreatitis requiring immediate treatment. Even after the inflammation heals, the patient may have a damaged pancreas with a blockage in the main pancreatic duct that continues to cause problems.
These problems can be fixed by draining the blocked off part of the pancreatic duct into the small intestine with a form of the Puestow procedure. It also may be treated with removal of the damaged and non-drained portion of the pancreas (a distal pancreatectomy).