Effect of beam hardening on arterial enhancement in thoracoabdominal CT angiography with increasing patient size: an in vitro and in vivo study.

Purpose: To assess the effect of beam hardening on arterial enhancement in thoracoabdominal computed tomographic (CT) angiography in various body sizes in a phantom and in a clinical study.

Materials And Methods: An abdominal aortic phantom was placed in three cylindrical water containers simulating a small, an intermediate, and a large patient (diameters of 22, 30, and 40 cm, respectively). CT scanning was performed at 80, 100, and 120 kVp, and aortic attenuation was assessed.