Pancreaticoduodenal arcades and dorsal pancreatic artery: comparison of CT angiography with three-dimensional volume rendering, maximum intensity projection, and shaded-surface display.

OBJECTIVE: The objective of this study was to compare the ability of CT angiography to depict the pancreaticoduodenal arcades and the dorsal pancreatic artery using the techniques of three-dimensional (3D) volume rendering, maximum intensity projection (MIP), and shaded-surface display (SSD). SUBJECTS AND METHODS: Twenty-seven patients were selected at random from a group of 42 patients undergoing arterial-phase helical CT angiography before liver transplantation. CT angiograms were constructed from identical data sets using 3D volume rendering, MIP, and SSD.
RESULTS: Seventy-two vessels were evaluated in 27 patients. Three-dimensional volume rendering depicted 24 anterior and 22 posterior arcades and 26 dorsal pancreatic arteries; combined MIP and SSD depicted 14 anterior and 13 posterior arcades and 19 dorsal pancreatic arteries. Thirty vessels with diameters of between 2 and 3 mm were well seen with 3D volume rendering but were incompletely depicted with MIP and SSD. Sixteen vessels with diameters of greater than 3 mm were well seen using all three techniques. Twenty-six vessels with diameters of less than 2 mm were faintly seen with 3D volume rendering but were unidentifiable with MIP and SSD.
CONCLUSION: Three-dimensional volume rendering is superior to MIP and SSD in the depiction of pancreaticoduodenal arcades and dorsal pancreatic arteries. Unlike the other rendering techniques, 3D volume rendering can also show relationships between these vessels and pancreatic parenchyma and adjacent structures.