Size of common bile duct stones on MRCP predicts likelihood of positive findings at ERCP

ACR Appropriateness Criteria® Jaundice

“…For diagnosis of CBD stones, MRCP (without IV contrast) has a reported sensitivity ranging from 77% to 88%, specificity between 50% to 72%, accuracy of 83%, positive predictive value between 87% to 90%, and negative predictive value between 27% to 72%, as compared to the gold standard of ERCP [57,58]. However, MRCP has diminishing sensitivity with decreasing stone sizes of <4 mm [58][59][60]. The reasons for the low specificity of MRCP for tiny CBD stones are multifactorial.…”

“…One such factor is that there is an increased likelihood for spontaneous stone passage when stones are <4 mm in size; therefore, the stone may be present for the MRCP but have passed by the time of the ERCP. Similarly, the sensitivity of MRCP may be affected by stones in the gallbladder that pass into the CBD between the MRCP and the ERCP [60]. Additionally, studies that compare MRCP to ERCP use ERCP as the gold standard, which intrinsically biases the results toward ERCP.…”

Analysis of Endoscopic Retrograde Cholangiopancreatography in Rural Appalachia

“…Although ERCP has proven useful in both identifying and treating etiologies of primary biliary ductal obstruction, its precise role has been scrutinized with the advent of magnetic resonance cholangiopancreatography (MRCP). 1 Although MRCP is a less invasive procedure it offers diagnostic, not therapeutic, value in the assessment of biliary disease while presenting both a greater financial burden and difficulty in allocating limited health care resources. 2,3 Although ERCP has proven an invaluable technique in surgical and gastroenterological practice, its exact utility in the Appalachian population has yet to be precisely elucidated.…”