The purpose of this study was to investigate the contrast effect of arteries and the distribution of contrast medium along the z-axis in three-dimensional computed tomography angiography from neck to lower extremity (neck-lower-extremity 3D-CTA) using the F variable-speed injection method.
The subjects were 112 patients who underwent neck-lower-extremity 3D-CTA. In the fixed-speed injection method, contrast medium was injected at the same rate for 35 s. In the variable-speed injection method, contrast medium was injected for 35 s at varying rates. CT values were measured in the common carotid artery (CCA), ascending aorta (AAo), abdominal aorta (AA), superficial femoral artery (SFA), popliteal artery (PA), anterior tibial artery (ATA), and dorsalis pedis artery (DPA). We normalized the CT values of each artery for each patient, defined the contrast uniformity, and compared them. We also performed a four-level visual evaluation.
A significant difference was found in the PA, ATA, and DPA, with the variable-speed injection method showing a higher CT value than the fixed-speed injection method (p<0.01). There were no significant differences in the CCA, AAo, AA, and SFA. Similarly, the variable-speed injection method scored significantly higher in the visual evaluation.
The variable-speed injection method is useful in neck-lower-extremity 3D-CTA.