Keywords:
Biliary Tract / Gallbladder, Gastrointestinal tract, Abdomen, MR, Ultrasound, Diagnostic procedure, Cholangiography, Obstruction / Occlusion
Authors:
O. Abdulla1, S. J. Golding2; 1Bangor/UK, 2Oxford/UK
DOI:
10.1594/ecr2013/C-0604
Purpose
Calculous disease is the most common surgical disease of the biliary system [1].
Gallstone disease is associated with 8-20% incidence of the stones migrating into the common bile duct (CBD) [2].
It is critical that in the clinical management of CBD stones these stones are detected and treated appropriately before the development of cholangitis or pancreatitis [2].
Among the non-invasive imaging techniques currently advocated for evaluating the biliary tree,
ultrasonography (US) and computed tomography (CT) are the most frequently used in the initial evaluation of patients with symptoms and signs referable to the pancreaticobiliary system [1].
Despite the high sensitivity of ultrasound imaging in the detection of gallbladder calculi,
choledochal stones may remain undetected in a large percentage of patients [3-5].
Other invasive procedures for diagnosing common bile duct stones include endoscopic retrograde cholangiopancreatography (ERCP),
intraoperative cholangiography (IOC),
percutaneous transhepatic cholangiography (PTC) and endosonography (EUS).
ERCP is widely used because of its high sensitivity,
the resolution obtained with the technique and the ability to provide therapy on determination of the diagnosis,
with only a single invasive intervention such as stone removal,
endoscopic sphincterotomy or stent placement.
Magnetic resonance cholangiopancreatography (MRCP) is a well established radiologic tool for the evaluation of biliary tree (fig.
2 and 3).
The technique does not utilize ionizing radiation,
is non-invasive and no intravenous contrast is necessary.
Current evidence [6] suggests that MRCP might have great sensitivity and specificity to diagnose common bile duct stones similar to that at direct cholangiography and yet combine the patient comfort and safety associated with US.
The aim of this study is to evaluate what MRCP can add after transabdominal US in patients with choledocholithiasis,
and to perform a subgroup analysis to establish the characteristics of stones and bile duct status in patients who escaped detection by US and were exclusively diagnosed by MRCP.