Demonstration of the Adamkiewicz artery in patients with descending or thoracoabdominal aortic aneurysm: optimization of contrast-medium application for 64-detector-row CT angiography.

Our aim was to prospectively investigate the contrast agent concentration and the infusion rate to obtain optimal images of the Adamkiewicz artery by 64-row MDCT. Eighty patients were divided into four groups based on the following protocol: A, 100 mL of 300 mg I/mL at 5.0 mL/s; B, 100 mL of 350 mg I/mL at 5.0 mL/s; C, 100 mL of 300 mg I/mL at 3.5 mL/s; D, 100 mL of 350 mg I/mL at 3.5 mL/s. Quantitative evaluation was performed by calculating mean aortic attenuation value from T5 to L3 level. Visual evaluation of the Adamkiewicz artery was also performed. In a quantitative evaluation, the rapid injection (A, 473.4 +/- 82.6 HU; B, 506.7 +/- 71.9 HU) was significantly superior to the slow injection (C, 371.3 +/- 65.1 HU; D, 391.5 +/- 60.8 HU). In a visual evaluation, the Adamkiewicz artery was assessable in 15 of 20 (75%), 16 of 20 (80%), 9 of 20 (45%), and 10 of 20 (50%) patients in groups A, B, C, and D, respectively. The injection protocol of 1.75 g iodine/s provides both the adequate aortic attenuation of more than 450 HU to assess the Adamkiewicz artery and the best visualization of the Adamkiewicz artery in 64-row MDCT.