According to the American Gastroenterological Association, gallstone disease is a common medical problem, affecting 10-15% of the U.S. population. The gallbladder is a sac that lies on the undersurface of the liver. It is connected to the liver and the intestine by small tubes, or ducts. The primary job of the gallbladder is to store bile, which is secreted continuously by the liver, until the bile is needed to aid in digestion. Gallstones are pieces of hard solid matter in the gallbladder that form when components of bile form into crystals. Sometimes the crystals and stones are too small to see with the naked eye. This condition is called biliary sludge.

The most typical symptom of gallstone disease is severe steady pain in the upper abdomen or right side. The pain may also be felt between the shoulder blades or in the right shoulder. Sometimes patients also have vomiting or sweating. It is thought that gallstone pain results from blockage of the gallbladder duct (cystic duct) by a stone. When the blockage is prolonged (greater than several hours), the gallbladder may become inflamed. This condition is called acute cholecystitis.

More serious complications may occur when a gallstone passes out of the gallbladder duct and into the main bile duct. If the stone lodges in the main bile duct, it can lead to a serious bile duct infection. If it passes down the bile duct, it can cause an inflammation of the pancreas, which has a common drainage channel with the bile duct. Either of these situations can be extremely dangerous.

The most accurate tests to identify stones in the bile duct include: Magnetic resonance imaging (MRI) scans, Endoscopic ultrasound (EUS), and Endoscopic retrograde cholangiopancreatography (ERCP). During ERCP, if the gastroenterologist finds stones in the bile then these stones may be removed endoscopically.