MULTIPLANAR CT PANCREATOGRAPHY AND DISTAL CHOLANGIOGRAPHY WITH MINIMUM INTENSITY PROJECTIONS

PURPOSE: To develop a technique of projectional computed tomographic ( CT) cholangiopancreatography (CTCP). MATERIALS AND METHODS: Sixty-one patients underwent CT for suspected biliary or pancreatic abnormalitie s. The axial CT and CTCP techniques included spiral scanning during th e portal venous phase and thick-slab minimum intensity projections. Vi sualization of pancreatic and extrahepatic bile ducts (divided in five duct segments per patient) was graded blindly on a scale of 1-5 by a consensus of two radiologists. Two hundred seventy-seven duct segments were used to compare axial CT and CTCP in the depiction of duct segme nts and dilatation; 109 segments were used to compare CTCP with ERCP. RESULTS: Fifty-six of 277 duct segments were not visualized on axial C T images; 15 segments were not visualized on CTCP images (P < .001). T here was no statistically significant difference between the number of segments missed with ERCP and the number missed with CTCP: nine and t hree of 109 segments, respectively. Duct visualization was equal on ax ial CT and CTCP images in 35 of 109 duct segments and was superior on CTCP images in all but one of the remaining segments (P < .001). Duct visualization on CTCP images was equal to that on ERCP images in 35 se gments, superior in nine, and significantly inferior in 66 (P < .001). CONCLUSION: CTCP improves CT depiction of pancreatic and bile ducts w ith a quality that approaches that of ERCP.