ERCP (Endoscopic Retrograde Cholangio-Pancreatography)
If there is a suspicion that a gallstone is present in the common bile duct (history of pancreatitis, jaundice or cholangitis or if the liver function tests are abnormal) then an ERCP examination can be used to detect the stone and remove it. ERCP involves the passage of a flexible camera (endoscope) through the mouth, gullet and stomach into the duodenum. This is done under mild sedation in a patient who has been starved for 6 hours (so that the stomach is empty). You will see from the anatomy section that the common opening of the bile duct and pancreatic duct can then be entered. Contrast medium (X-ray dye) can be injected to visualise the ducts. The picture below shows gallstones in the common bile duct (they appear black in the white bile duct as it tapers at the bottom. You can also see the endoscope in the x-ray).
 |
 |
| Endoscope | X-ray of gallstones in the bile duct |
These stones can be removed using a balloon or a basket. The outlet of the bile duct can be widened by cutting with diathermy (the use of an electric current to generate heat). Sometimes it may not be possible to remove the stones and a plastic tube (stent) may be inserted to allow drainage of the bile - this will allow the jaundice to settle before an operation is carried out. If the bile duct has to be explored at open operation to remove stones, a rubber tube is left in place for 10-14 days. This is called a 'T-tube' - a small part is left in the bile duct and the long tail brought to the skin surface. This allows the bile duct to heal without allowing leakage of bile. An X-ray is taken with contrast in the T-tube before it is removed.
Complications that may arise from ERCP:
 | pancreatitis - inflammation of the pancreas gland may occur as the pancreatic juice is temporarily prevented from emptying into the gut by the endoscope. The risk of this can be minimized by avoiding the injection of contrast medium into the pancreatic duct. |
| bleeding - if the diathermy is used to cut the opening of the bile duct into the duodenum (in order to widen it) bleeding may occur. Usually this will settle without further treatment. Rarely an operation may be necessary. |
| perforation - this may occur if the diathermy cut is a bit too long and the duodenum is cut beyond the exit of the bile duct. This may be treated with antibiotics but may require surgery. |