How is cholelithiasis typically diagnosed?

• A. CT scan of the abdomen
• B. Abdominal ultrasound of the right upper quadrant
• C. MRI of the abdomen
• D. X-ray of the abdomen

Answer: (B)

Cholelithiasis, or the formation of gallstones, is most commonly diagnosed using an abdominal ultrasound of the right upper quadrant. This imaging technique is preferred because it is non-invasive, does not use ionizing radiation, and is particularly effective at visualizing gallstones and assessing the gallbladder's condition. The ultrasound can reveal the presence of stones, measure the size of the gallbladder, and detect any complications such as inflammation or bile duct obstruction.

Other imaging methods, such as a CT scan, may also identify gallstones, but they are often reserved for cases where other abdominal pathologies are suspected alongside cholelithiasis. MRI is useful in evaluating soft tissue structures and certain liver conditions but is not typically the first choice for diagnosing gallstones. An X-ray of the abdomen is less effective in diagnosing cholelithiasis since most gallstones are not radiopaque and thus may not be visible on an X-ray.