MRCP Magnetic Resonance Cholangiopancreatography

When patients have suspected biliary or pancreatic disease, ultrasound imaging is the traditional screening technique. However, ultrasound is limited in its ability to image abnormalities in the biliary and pancreatic ductal systems and further evaluation may be necessary with either endoscopic retrograde cholangiopancreatography (ERCP) or MRCP.

ERCP is a minimally invasive procedure that combines endoscopy with the injection of iodinated contrast agent into the biliary and pancreatic ducts. ERCP has the advantage of combining diagnosis with intervention. In addition, manometry can be performed and the ampulla can be directly visualized. However, ERCP carries a small but significant risk of complications, including pancreatitis, hemorrhage, and perforation. At MGH, the complication rate is 1-2%, significantly lower than the national average. In addition, ERCP may be difficult in patients with post-surgical anastomotic complications.

Normal MRCP image showing the common bile duct (curved arrow) and the pancreatic duct (arrow). Note the fluid filled duodenum.

Common Bile Duct Stone. MRCP image shows a dilated bile duct with a dark stone (arrow) in its distal end

MRCP image that shows a dilated main pancreatic duct and abnormal side branches, which are diagnostic of chronic pancreatitis

In this image, we see a dilated common bile duct that is obstructed by a large stone (arrow). The common bile duct conveys bile from the liver into the intestine. Stones can form in the bile ducts, and obstruct them, often leading to severe pain. MRCP is a safe, non-invasive way to study the biliary system.