Comparison of capability of abdominal 320-detector row CT and of 16-detector row CT for small vasculature assessment.

The purpose of our study was to compare the capability of the 320-detector row CT (area-detector CT: ADCT) using the step-and-shoot scan protocol for small abdominal vasculature assessment with that of the 16-detector row CT using the helical scan protocol. Contrast-enhanced abdominal CT for preoperative assessment was administered to 25 patients, 18 of whom, suspected of having lung cancer, underwent ADCT using the step-and-shoot scan protocol, while the remaining 7, suspected of having renal cell carcinoma, underwent 16-MDCT using the helical scan protocol. Two experienced abdominal radiologists independently assessed renal interlobar and arcuate as well as mesenteric marginal (Griffith point) arteries by means of a 5-point visual scoring systems. Kappa analysis was used for evaluation of interobserver agreement. To compare the visualization capability of the two systems, the scores for each of the arteries were compared by using the Mann-Whitney U-test. Overall interobserver agreements for both systems were almost perfect (κ>0.78). Visualization scores for renal interlobar and arcuate, (p<0.0001) and mesenteric marginal (Griffith point) arteries (p<0.05) were significantly higher for ADCT than for 16-detector row CT. ADCT using the step-and-shoot scan protocol for small abdominal vasculature assessment can be considered superior to 16-detector row CT using the helical scan protocol.