1.   All patients underwent an abdominal ultrasound examination before endoscopic retrograde cholangiopancreatography.

2.   Upper abdominal ultrasound and abdominal computed tomography were normal.

3.   All patients had standard haematological and biochemical tests, and an upper abdominal ultrasound scan.

4.   Abdominal ultrasound imaging showed non-dilated bile ducts, several fluid collections, and guided puncture yielded bile.

5.   Abdominal ultrasound showed a stenotic area in the mid-CBD, with prestenotic dilation.

6.   Remarkably, previous abdominal ultrasound showed non-dilated intrahepatic bile ducts despite the presence of major bile duct injury in four patients.