Abstract: Objectiv The purpose of this study was to compare magnetic resonance cholangiopancreatography （MRCP） with color Doppler ultrasound （US） in diagnosis of patients with common bile duct stones. Methods 102 patients with suspected common bile duct stones were recruited in our hospital,and all of them were examined by color Doppler ultrasound and MRCP. The diagnostic efficacies between the two approaches were evaluated by area under the receiver-operating characteristic curve（AUC）. Results Out of the 102 patients with suspected choledocholithiasis,90 were diagnosed having common bile duct stones by post-operational pathology. The US demonstrated single stone in 39（43.3%） and multiple stone in 25（27.8%）,while the MRCP found them in 46（51.1%） and 39（43.3%）,respectively,with the detection rate of 94.4% by MRCP,significantly higher than 71.1%（P<0.05） by US;the detection rates by MRCP in stones with diameters of >1.0 cm,0.5-1.0 cm and <0.5 cm were 36.7%,50.0% and 7.8%,significantly different as compared to 34.4%,35.6% and 1.1% by US （P<0.05）;the diameters of stones showed by MRCP were （1.1~0.8）cm,much smaller than （1.4~0.6）cm by US （P<0.05）,while there was no significant difference between the diameters of undetectable stones by the two methods 【（0.8~0.2） cm vs.（0.6~0.4） cm,P>0.05】;the sensitivity,specificity and Youden's index by US were 71.1%,75.0% and 0.5,while they were 94.4%,91.7% and 0.9 by MRCP（P<0.05）. Conclusion MRCP is a sensitive approach in diagnosing common bile duct stones,which might help clinicians to make decisions.

Key words: Choledocholithiasis, Magnetic resonance cholangiopancreatography, Color Doppler ultrasound, Diagnostic efficacy