Cholelithiasis is the medical term for the presence of gallstones within the gallbladder. Gallstones form when substances in bile, particularly cholesterol or bilirubin, crystallize and accumulate into solid masses. On ultrasound, gallstones have a classic appearance: they are echogenic (bright), usually mobile, and produce a clean posterior acoustic shadow. Ultrasound is the gold standard for detecting gallstones, with a sensitivity greater than 95 percent, making it far more accurate than any other imaging method for this purpose. Cholelithiasis is extremely common, affecting approximately 10 to 15 percent of the adult population, and is one of the most frequent findings encountered during routine abdominal ultrasound examinations.
Sonography Term