Diagnostic and Interventional Radiology
Abdominal Imaging - Original Article

Ectopic opening of common bile duct into the duodenal bulb: magnetic resonance cholangiopancreatography findings


Department of Radiology, Ankara University School of Medicine, Ankara, Turkey

Diagn Interv Radiol 2020; 1: -
Read: 52 Published: 10 May 2021

Purpose: We aimed to evaluate spectrum of MR cholangiopancreatography (MRCP) findings in patients with ectopic opening of common bile duct (CBD) into the duodenal bulb and to determine the efficacy of MRCP technique in diagnosis.

Methods: Morphologic and morphometric MRCP/MRI features in 16 patients and 36 controls were retrospectively analyzed by 2 radiologists. The frequency of MRCP findings was determined. The significance of difference between the MRCP observations in patients and controls were evaluated statistically and the diagnostic efficacy of MRCP was investigated.

Results: Hook-shaped ending of CBD and bulbar deformity were the most frequent morphologic findings seen on MRCP in ectopic bulbar opening. Mean pylorus–papilla distance and mean CBD length were significantly shorter and median diameter of CBD was significantly larger than control group (28.6±15.3 mm, 33.7±12.8 mm, 8.6 (2-16) mm, 66.7±11.7 mm, 50.3±14.4 mm, 3.2 (1.5- 10) mm, p < 0.001, respectively). ROC analysis showed sensitivity and specificity of MRCP in the diagnosis were 87.5% and 100%, respectively, if any three of the four signs (hook-shaped ending of CBD, bulbar deformity, large, and short CBD) were present in a patient whose pylorus-papilla distance was <50 mm.

Conclusion: At MRCP, presence of short, and large CBD with hook-shaped ending in deformed duodenal bulb may support the diagnosis of ectopic biliary drainage.

EISSN 1305-3612