Brief Answer:
There could be a stone or a mass( benign or malignant).

Detailed Answer:
Hello Dear,
Thanks for choosing HealthcareMagic for your query.
I've gone through your details and I appreciate your concerns.

First, let's understand what does the test means this will help you understand things better.
A cholangiogram is a special x-ray procedure that is done with contrast media to visualize the bile ducts after removal of the gallbladder.The bile ducts drain bile from the liver into the duodenum through a cystic duct(arises from gall bladder) and hepatic duct originating from liver and merging with cystic duct to form a big vessel called common bile duct.

Now let's analyze the reports-
When the gallbladder is removed, the duct originating from it termed as the cystic duct is tied up. Slowly and slowly it gets opaque due to deposition of calcium in it(Part of programmed cellular death)-So it's a natural thing and you need not worry about it.

A small filling defect.....-Cystic duct joins with a hepatic duct to form common bile duct which drains into the intestine. During cholangiogram, a XXXXXXX is injected into these ducts. If there is no obstruction (like stone) then XXXXXXX should diffuse equally in every part of these ducts. However, filling defect means that some parts don't show diffusion of XXXXXXX normally(Dye can't fill that part).

It is either suggestive of a stone or a mass in duct.
An MRI or CT scan of the hepatobilliary system should be done to see the exact cause of filling the defect.

Hope this is understood.
Please feel free to follow-up.

Thanks!

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