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The use of CT or MRI for the one-stage placement of stents in biliary obstructions.

PURPOSE
This study describes and evaluates a simple method of percutaneous intervention planning in order to treat obstructed biliary systems using computed tomography (CT) or magnetic resonance imaging (MRI).


MATERIALS AND METHODS
CT (n=18) and MRI (n=31) examinations, which were performed during the imaging work-up of 31 patients with malignant biliary obstruction, were used to plan transhepatic percutaneous biliary intervention. The appropriate intrahepatic duct, the entry point on the skin, and the puncture direction and depth were determined on axial CT or MR images. Under fluoroscopic guidance, a 21-G needle was used for puncture, and the puncture was followed by a percutaneous transhepatic cholangiography, the placement of a stent, and the placement of an external drainage catheter.


RESULTS
The biliary system was successfully accessed on the first attempt in 16 patients (51.6%). Second or third attempts were required in eight (25.8%) and two (6.4%) patients, respectively, whereas more than three attempts were necessary for the remaining five (16.3%) patients. One-stage percutaneous transhepatic biliary stent placement was performed in 29 patients (93.5%). Two (n=1) and three (n=1) interventional sessions were required in order to successfully complete stent placement in the remaining two cases. The mean fluoroscopy time for one-stage biliary stent placement was 12.6 min +/- 2.6 min, and no major complications were noted.


CONCLUSION
Thorough CT/MRI-based planning is suggested prior to the interventional treatment of malignant biliary obstruction so as to reduce the number of needle passes, the duration of the procedure, the fluoroscopy time, and the number of complications.