Commom Hepatic Duct

[sonotech]

Would you consider a 6-7 mm common hepatic duct dilated in a sixteen year old with a disorder of the red blood cells(anemia) who presents with jaundice, right upper quadrant pain and has sludge and stones in the gallbladder? Could there be a stone in the bile duct even though it wasn't seen by ultrasound or MRCP?

[sonotech]

Thank you for your reply. It was very helpful. I also later discovered that there was a possible 3mm filling defect on MRCP in the distal CBD that could suggest an artifact or possible stone so an ERCP was suggested for this patient. I was betting on a stone causing the jaundiced state, but I didn't realize the patient also had spherocytosis and jaundice could be a condition from this disease. I learn something new everyday. I am curious as to what the results from the ERCP will show now. I did call the 6-7 mm CBD dilated but even knowing the patient's history of spherocytosis, maybe it's still possible there could be a very small stone?? However, I was told the patient's jaundiced state is more than likely from spherocytosis. This is a tough case like you said.

I was also told that up to age 50 the CBD is WNL up to 6mm and after age 50 add 10 mm. Is that correct?

Thanks for all your help!
Sonotech

[Dr. Kokil Mathur]

Hi!
The common hepatic duct is usually 6 mm in diameter so a 6-7mm diameter can be taken as a normal variation. A 16 year old can be considered an adult. If the diameter was 7 mm or more then yes, there is always a benefit of doubt that there could be a stone. However, there have been instances when stones were missed, could not be palpated during surgery and were yet present and demonstrated on visualizing the duct.  Usually MRCP is conclusive, unless the stone was very small. This is a very tough diagnosis to make on net. Please discuss the report with the treating doctor. Take care!