Gallstones refer to the solid material that can form when bile precipitates. Initially, this takes the form of small crystals, which can ultimately clump together and create larger solid pieces of matter. Most gallstones are primarily made up of cholesterol and are therefore referred to as cholesterol stones. Gallstones can actually be quite tiny, almost like a grain of sand or can grow both in size and in number. The gallbladder can actually accumulate hundreds of stones in some people. Sometimes the gallbladder contains only crystals, which can be just as problematic, but sometimes harder to diagnose. This condition is called biliary sludge.
Gallstone disease is a common problem affecting 10-15% of the population in the United States. Almost one million new cases of gallstone disease are diagnosed every year and approximately ¼ of these require treatment.