One afternoon in March 2008, Ms. Wu, a villager in a Guangdong county, was working when she suddenly experienced severe pain in her right upper abdomen. The pain was persistent and increased in paroxysms, making her unable to stand up straight, and was accompanied by a bout of nausea and vomiting. On the second day, she also had fever and yellow eyes. She understood that her gallstones had returned. A CT scan at the local hospital the next day confirmed Ms. Wu’s fears, showing several stone shadows in her common bile duct, 1.2 to 1.5 cm in diameter. In the five years prior to this, Ms. Wu had had three gallstones. The first attack was in 2003, when she underwent open surgery at a local hospital to remove her gallbladder and have the common bile duct explored for stones. After the surgery, a T-tube was placed in the common bile duct for drainage. However, 2 years after the surgery, Ms. Wu had 2 more occurrences of common bile duct stones, both of which were retrieved at the local hospital with open surgery of the common bile duct. The first 3 stone operations left a “zigzag” surgical scar on Ms. Wu’s right upper midsection. Now, facing this 4th attack, the doctor who operated on her did not dare to do it for her. Therefore, Ms. Wu came to Guangzhou to prepare for another surgery to remove the stone. After examination, our surgeon concluded that the previous 3 operations had not only left surgical scars on Ms. Wu’s abdomen, but also left multiple healing scars on her bile ducts, making it difficult and risky to operate again. Ms. Wu was advised to undergo endoscopic minimally invasive common bile duct lithotripsy instead of open surgery as before. It turns out that the bile ducts originate in the liver, and the bile ducts in the liver merge to form the common hepatic duct, which extends downward to the common bile duct. The opening of the lower part of the common bile duct is also connected to the pancreatic duct, and the common bile duct and the pancreatic duct open together at the papilla of the duodenum. Between the common hepatic duct and the common bile duct, there is a cystic duct, which connects to the gallbladder. If a stone grows in the common bile duct and blocks the opening of the common bile duct, the bile cannot be drained out and jaundice will occur. The blockage of the bile duct and the lack of bile drainage can also lead to bacterial infections, which can lead to cholangitis or cholecystitis. Since the bile ducts are connected to the pancreatic ducts, pancreatitis may also occur. Therefore, gallstones can cause abdominal pain, fever and jaundice during an attack, which can be life-threatening in severe cases. In the past, the treatment of bile duct stones focused on open surgery to remove stones. In recent years, with the development of endoscopic technology, many bile duct stones that previously required surgery can be removed through endoscopic (duodenoscopy, or in some places, pancreaticobiliary) minimally invasive procedures. Endoscopic stone extraction involves inserting an endoscope through the mouth, passing through the stomach to the duodenum, and finding the duodenal papilla, the common opening of the common bile duct and pancreatic duct, in the descending duodenum. Through the endoscopic channel, a contrast tube is inserted into the papilla, selectively enters the common bile duct and injects a contrast agent, which clearly shows the size and number of stones in the bile duct under X-ray. This procedure is called “transendoscopic retrograde cholangiopancreatography” (also called ERCP). Then, the doctor inserts an electric knife to cut the papilla and expose the common bile duct. Then, through the endoscopic channel, a lithotripsy mesh is inserted into the common bile duct and the stone is removed. If the stones are large, a lithotripsy basket can be inserted to crush the stones before they are removed with the mesh blue. This technique allows many patients who used to need open surgery to remove bile duct stones to avoid opening the abdomen, reducing the patient’s pain and saving hospital time and costs. Ms. Wu was fortunate. At our Gastrointestinal Endoscopy Center, the doctor removed several stones from her common bile duct at once through a painless and minimally invasive endoscopic approach. During the extraction, the doctor found that Ms. Wu’s stones had a hard “core”, but the stones were largely sediment-like. This type of stone is difficult to remove even with surgical treatment. Some of the tiny stones left after surgery can become the “core” and bile will keep adhering to its surface to form large stones, leading to recurrence. This is the reason why Ms. Wu had gallstones 4 times in 5 years. In order to reduce the chance of recurrence, the gastroenterologist placed a drainage tube in Ms. Wu’s common bile duct after the endoscopic stone extraction. The other end of this drainage tube came out of Ms. Wu’s nasal cavity and was connected to an external drainage bag. Through this nasobiliary tube, the doctors were able to flush the common bile duct with saline several times in the days after the endoscopic stone extraction, so that the residual microscopic stones could be discharged into the intestinal cavity, thus greatly reducing the chance of recurrence of gallstones.