All 37 patients were examined with dynamic contrast-enhanced CT with a 64-channel MDCT scanner (Aquilion 64, Toshiba, Tochigi, Japan) before TACE. Images were reconstructed in a section thickness of 5 mm with 5-mm intervals.
Non-ionic contrast material, a bolus of 100 ml iopamidol (370 mg I/ml, Iopamiron 370; Bayer Healthcare, Osaka, Japan) was administered intravenously via typically an antecubital vein at a rate of 3 to 4 ml/second with a power injector (Auto Enhance A-60; Nemotokyorindo, Tokyo, Japan).
For setting the adequate starting time of hepatic arterial phase scanning, an automatic bolus-tracking program (Real prep, Toshiba) was used. A circular region of interest (ROI) with an area of 50 pixels was placed in the aorta at the level of the celiac axis. The hepatic arterial phase scan started automatically 22 second after the threshold enhancement of 50 HU was reached in the aorta with the bolus-tracking program. The portal venous phase scan started 75 second just after contrast material injection.
Non-ionic contrast material, a bolus of 100 ml iopamidol (370 mg I/ml, Iopamiron 370; Bayer Healthcare, Osaka, Japan) was administered intravenously via typically an antecubital vein at a rate of 3 to 4 ml/second with a power injector (Auto Enhance A-60; Nemotokyorindo, Tokyo, Japan).
For setting the adequate starting time of hepatic arterial phase scanning, an automatic bolus-tracking program (Real prep, Toshiba) was used. A circular region of interest (ROI) with an area of 50 pixels was placed in the aorta at the level of the celiac axis. The hepatic arterial phase scan started automatically 22 second after the threshold enhancement of 50 HU was reached in the aorta with the bolus-tracking program. The portal venous phase scan started 75 second just after contrast material injection.