On MRCP (Magnetic Resonance Cholangiopancreatography), the 'double duct sign' refers to simultaneous dilation of both the common bile duct and the pancreatic duct. This sign is MOST associated with which condition?
- A Carcinoma of the head of the pancreas or periampullary carcinoma ✓
- B Primary sclerosing cholangitis
- C Chronic pancreatitis with pseudocyst
- D Common bile duct stone
Correct answer: A. Carcinoma of the head of the pancreas or periampullary carcinoma
Explanation
The double duct sign — simultaneous dilation of both the common bile duct (CBD) and main pancreatic duct (MPD) — occurs when a periampullary or pancreatic head mass obstructs both ducts at or near the ampulla. It is highly associated with carcinoma of the head of the pancreas or periampullary carcinoma (ampullary, duodenal, distal cholangiocarcinoma). PSC causes strictures and irregular beading. Chronic pancreatitis can dilate the MPD but typically with calcifications. A CBD stone obstructs only the CBD.
Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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