History: 55 year old female with abdominal pain.
This is the typical appearance of cholelithiasis (gallstones) on CT. There are multiple types of gallstones, including cholesterol stones (the most common type) and pigment stones. Ultrasound is usually the imaging method of choice to diagnose cholelithiasis, however, they can be seen on CT up to 80% of the time. Cholelithiasis is common in the United States, affecting nearly 10-15% of patients (6-20% of patients worldwide); however, it is usually asymptomatic. They are 2-3x more common in women, and prevalence increases with increasing age. Acute cholecystitis is seen with sudden inflammation in the gallbladder and is caused by gallstones in 90% of cases.