Common bile duct stones may be small or large, single or multiple, the incidence increases with age. Biliary stones present almost always as low signal intensity on MR images. Therefore, the stone is identified as a round or oval- shaped "signal void" within the common bile duct (CBD), surrounded by the high signal intensity bile, CBD stone can present as sharp cutoff of a CBD at the ampulla, often with a well-marginated “meniscus” configuration, CBD stone may be associated with CBD dilatation and/or dilated intrahepatic biliary tree.
To evaluate MRCP signs in detecting CBD stones in patients with obstructive jaundice.
PATIENTS AND METHODS:
The study included 50 patients with jaundice suspecting to have CBD stones as a cause of their complaint ,MRCP parameters include: CBD diameter, meniscus sign ,Status of intrahepatic and extrahepatic ducts, Gall bladder status, Pancreatic duct status Statistical analyses for the results were done.
MRCP diagnose choledocholithiasis in 49(98%) out of 50 patients with a sensitivity of 98%, Accuracy =98%, the specificity of MRCP in diagnosing choledocholithiasis in our study was 95%, P value= 0.001. MRCP show filling defect in 31 patients (3 of them show multiple filling defects) giving Accuracy =62%, sensitivity rate 62%, specificity rate 90%, P value= 0.0001. MRCP show meniscus sign in 18 patients giving Accuracy =36%, sensitivity rate 36%, specificity rate 95%, P value= 0.0001. MRCP show CBD dilatation in 48 patients giving Accuracy =96%, sensitivity rate 96%, specificity rate 95%, P value= 0.001.
MRCP is a non–invasive investigation with high sensitivity, specificity, positive and negative predictive values in detection of CBD stones. Gathering well-defined radiological signs of CBD stones in MRCP allows good diagnostic accuracy. CBD dilatation is the more sensitive sign of detecting CBD stone while meniscus sign is more specific sign for detecting CBD stone in MRCP.