For suspected gallstones in the abdomen, which imaging modality is preferred?

For suspected gallstones in the abdomen, which imaging modality is preferred?

• A. X-ray abdomen
• B. CT scan
• C. Ultrasound
• D. MRI

Answer: (C)

Ultrasound is the best initial imaging for suspected gallstones because it directly detects stones within the gallbladder with high sensitivity, and it can quickly assess the gallbladder for signs of inflammation or complications. It is safe and noninvasive—there's no radiation and no contrast needed—which makes it ideal for emergency or outpatient evaluation. On ultrasound, stones appear as bright echogenic foci with posterior acoustic shadowing, and the exam can also evaluate gallbladder wall thickening, pericholecystic fluid, and the presence of a positive Murphy sign, all of which help identify cholecystitis or other biliary pathology. In contrast, plain abdominal X-rays miss most gallstones since many are radiolucent; CT is less sensitive than ultrasound for stones and involves radiation and contrast risks; MRI/MRCP provides excellent anatomy but is more costly and less readily available as a first test. So, the ultrasound approach offers the best combination of accuracy, safety, and practicality for suspected gallstones.

Ultrasound is the best initial imaging for suspected gallstones because it directly detects stones within the gallbladder with high sensitivity, and it can quickly assess the gallbladder for signs of inflammation or complications. It is safe and noninvasive—there's no radiation and no contrast needed—which makes it ideal for emergency or outpatient evaluation. On ultrasound, stones appear as bright echogenic foci with posterior acoustic shadowing, and the exam can also evaluate gallbladder wall thickening, pericholecystic fluid, and the presence of a positive Murphy sign, all of which help identify cholecystitis or other biliary pathology. In contrast, plain abdominal X-rays miss most gallstones since many are radiolucent; CT is less sensitive than ultrasound for stones and involves radiation and contrast risks; MRI/MRCP provides excellent anatomy but is more costly and less readily available as a first test. So, the ultrasound approach offers the best combination of accuracy, safety, and practicality for suspected gallstones.