Finding-the-Path: Abdominal ultrasound

Abdominal ultrasound scans show a mildly dilated common bile duct measuring 8 mm in diameter (arrow). An echogenic calculus with acoustic shadowing is visible in the distal portion of the common bile duct (arrow). There is no intrahepatic biliary dilatation. The gallbladder appears contracted (arrow). These findings are consistent with choledocholithiasis resulting in early or incomplete biliary obstruction.

Which study to you request next?

• MR cholangiogram
• Abdominal CT
• Endoscopic retrograde cholangiopancreatography with stone extraction
• Oral cholangiogram
• Percutaneous cholangiogram