: a calculus (as of cholesterol) formed in the gallbladder or biliary passages—called also biliary calculus, cholelith
Mass of crystallized substances that forms in the gallbladder. The most common type occurs when the liver secretes bile with too much cholesterol to stay in solution. Liver damage, chronic gallbladder disease, or biliary-tract cancer may predispose one to stone formation. In the gallbladder, stones may cause inflammation or produce no symptoms. A stone obstructing the bile duct causes severe pain (biliary colic). Gallstones usually must be removed with the gallbladder or broken up with ultrasound. In some cases a stone can be treated by giving the patient bile salts, which help redissolve cholesterol. If the gallbladder must be removed, laparoscopy is the method of choice.