Test yourself
Common bile duct: find the parallel channel
4 questions. Pick an answer to see whether you are right and why. Your score appears at the end.
Question 1How do you separate the common bile duct from the hepatic artery at the porta hepatis?
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Answer d. Both tubes run anterior to the portal vein and look alike on greyscale. Colour Doppler shows flow in the artery and none in the duct.
Question 2Which measurement is the usual upper limit of normal for the common bile duct in an adult with a gallbladder?
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Answer d. Most references use 6 mm, with some using 7 mm. The duct widens with age, by about 1 mm a decade over 60, and up to 10 mm can be normal after cholecystectomy.
Question 3A 45-year-old with gallstones and jaundice has a common bile duct of 11 mm. What does this suggest?
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Answer d. An 11 mm duct is dilated in a 45-year-old with a gallbladder. With jaundice and gallstones, a stone in the duct is likely, and the patient needs further imaging and specialist review.
Question 4A patient with jaundice has a common bile duct of 5 mm on POCUS. What do you conclude?
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Answer a. Early obstruction and stones in the distal duct, hidden behind the duodenum, occur with a normal-calibre duct on bedside scanning.
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Four or five delegates per instructor, FAMUS-accredited faculty and long, supervised time on the probe.
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