In cholangiography CBD stone appears as ?
**Core Concept**
The underlying principle being tested is the radiological appearance of stones in the common bile duct (CBD) during cholangiography, a medical imaging technique used to visualize the bile ducts. Cholangiography involves injecting a contrast agent into the bile ducts to highlight their structure on X-rays. **CBD stones** are a common cause of biliary obstruction.
**Why the Correct Answer is Right**
Since the correct answer is not provided, I will explain the general concept. In cholangiography, a CBD stone typically appears as a filling defect, which means it shows up as an area where the contrast agent does not penetrate, indicating the presence of a solid object like a stone. This is because the stone blocks the flow of the contrast agent, creating a visible obstruction.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the correct answer provided, it's challenging to specify why each option is incorrect. However, generally, options that do not describe a filling defect or an obstruction in the CBD would be incorrect.
**Option B:** Similarly, without the correct answer, it's difficult to address each option specifically. Options that suggest the stone would enhance with contrast or not be visible would be incorrect.
**Option C:** Any option suggesting that the stone would not cause an obstruction visible on cholangiography would be incorrect.
**Option D:** An option that does not align with the typical radiographic appearance of a CBD stone would be incorrect.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that CBD stones can cause significant morbidity if not diagnosed and treated promptly. The appearance of a filling defect in the CBD during cholangiography is a critical diagnostic finding that requires further evaluation and possible intervention, such as endoscopic retrograde cholangiopancreatography (ERCP) for stone removal.
**Correct Answer:** Correct Answer: D. Filling defect