Brief Answer:
Dilated common bile duct and obstruction explained

Detailed Answer:
Hi XXXX,
Thanks for writing in to us.

I have read through your query in detail.
Please let me explain this in detail from basics.

The gall bladder stores bile which helps in digestion. The bile exits the gall bladder through the cystic duct. The cystic duct then joins the common bile duct through which the bile is transported to the duodenum or small intestine. The opening of the common bile duct into the duodenum is called ampulla of vater.
The common bile duct has got a proximal (upper half) and distal (lower half) portions. The lower half of common bile duct passes through the head of pancreas as it enters the duodenum.

An obstruction due to stone, stricture, tumour or cancer can develop anywhere along the course of the common bile duct. The causes the part of common bile duct above the are of obstruction to enlarge and is called dilatation.

The dilated common bile duct and obstruction is evaluated by ultrasound scan, CT scan, MRI scan and ERCP (endoscopic retrograde cholangiopancreatography)

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

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