Three-dimensional helical computed tomography cholangiography with minimum intensity projection in gallbladder carcinoma patients with obstructive jaundice: comparison with magnetic resonance cholangiography and percutaneous transhepatic cholangiography.

Objective:  Computed tomography (CT) is traditionally used for evaluation and staging of gallbladder carcinoma (GC). However, in the subgroup of patients with obstructive jaundice, magnetic resonance cholangiography (MRC) is generally required to assess the level of biliary obstruction. The present study was  undertaken  to  evaluate  the  diagnostic potential of three-dimensional helical CT cholangiography (3-D CTC) with minimum intensity projection (minIP), to determine the presence and level of biliary obstruction. Materials and Methods:  Twenty-five consecutive patients with proven GC, presenting with clinical and biochemical features of obstructive jaundice, over a 1-year period were included in the study. Dual phase helical CT data was obtained in the arterial and venous phases, respectively, after intravenous contrast injection using a pressure injector. Axial CT data (both arterial and venous phase) was studied for staging and resectability of tumor. Three-dimensional helical CT cholangiography using minIP obtained from the venous phase data set, was used to assess the level of biliary obstruction and isolation of hepatic segmental ducts. Three-dimensional helical CT cholangiography findings were compared with MRC and percutaneous transhepatic cholangiography (PTC) (gold standard). None of the patients were operated on as they were all considered inoperable on axial CT images due to extensive local disease or distant metastasis. Results:  In all patients, 3-D CTC demonstrated dilated intrahepatic ducts up to tertiary branch level. The 3-D CTC correctly diagnosed the level of biliary obstruction and demonstrated isolated segmental ducts in all patients and correlated well in all cases with MRC and PTC findings in this regard. However, the 3-D CTC did not add any additional information over the axial source images. Conclusion:  Three-dimensional helical CT cholangiography with minIP can correctly determine the level of biliary obstruction in patients with GC and may be a strong competitor with MRC, because it gives equivalent information with regard to the level of ductal obstruction even while being a part of an overall comprehensive CT staging study. Even though 3-D CTC did not provide additional information on top of the source images, the referring physicians found them very useful for conceptualization of the 3-D biliary anatomy.