Value of MR cholangiography in the diagnosis of obstructive diseases of the biliary tree: a study of 58 cases

Objective: The aim of this study was to evaluate magnetic resonance cholangiography (MRC) in the diagnosis of biliary tree obstruction. Methods: Fifty-eight consecutive patients underwent MRC (GYROSCAN ACS II 1.5 Tesla, TSE T2 axial/coronal-MIP sequences) for clinical and biochemical signs of main bile duct obstruction. MRC images were interpreted by two radiologists and consensus was established according to presence or absence of main bile duct dilation, choledocholithiasis, and malignant or benign stricture. MRC was compared to a final diagnosis established by ultrasound and CT in 19 cases, endoscopic retrograde cholangiopancreatography (ERCP) in 25, intraoperative cholangiography and exploration in 14, and clinical, biochemical, and histological presentation when relevant. Included were single or multiple choledocholithiasis (28, including 11 ≤ 3 mm), malignant (10) and benign (12) strictures, and intrahepatic cholestasis (9). Results: Overall, MRC was sensitive (94%) and specific (92%) in detecting main bile duct dilation and choledocholithiasis (86% and 97%), but was less sensitive (64%) for small stones ≤ 3 mm. Sensitivity for stones > 3 mm was 100%. For benign and malignant strictures, MRC was less sensitive (67% and 80%) but remained specific (98% and 96%). In the detection of normal main bile duct, MRC was highly sensitive (100%) and specific (94%). Diagnostic accuracy ranged from 91% to 98%. Conclusion: MRC appears to be specific for choledocholithiasis and sensitive except for small stones. Results for biliary stricture are less satisfactory, but remain specific. Our data confirm that MRC can be useful in the diagnostic workup of main bile duct obstruction.