Gallstones are very frequent finding following cholecystectomy (surgical resection of the gallbladder) and there can be as many as hundreds of them!These are hardened deposits of digestive fluid that can form in the gallbladder that can eventually block the exiting bile ducts and cause sudden, severe abdominal pain, known as biliary colic. They range in size from as small as a grain of sand to as large as a golf ball.