Table 1.

Details on protocols and phantoms used in the study

Physical Parameter Investigated	Scan Parameters	Reconstruction Parameters	Phantom Used
Water mean CT value and standard deviation versus dose and SAFIRE strength (Fig. 1)	120 kV, 300/200/100/50 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, 2 mm slice thickness, pitch 1.0	FBP:B31s SAFIRE: I31s S1, S2, S3, S4, S5	30 cm diameter water‐filled phantom
Water standard deviation versus different reconstruction kernels (Table 2)	120 kV, 200 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, 2 mm slice thickness, pitch 1.0	FBP:B31s, B36s, B40s, B70s SAFIRE: I31s, I36s, I40s, I70h S3	30 cm diameter water‐filled phantom
Noise power spectrum NPS (Fig. 2)	120 kV, 200 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, 2 mm slice thickness, pitch 1.0	FBP: B40s SAFIRE: I40s S1, S2, S3, S4, S5	30 cm diameter water‐filled phantom
CT number linearity and CT number accuracy (Table 3)	120 kV, 200 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, 2 mm slice thickness, pitch 1.0	FBP:B31s SAFIRE: I31s S1, S3, S5	Catphan 600, sensitometry module
Low contrast resolution (Fig. 3, Table 4)	120 kV, 300/200/100 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, 2 mm slice thickness, pitch 1.0	FBP : B31s SAFIRE: I31s S1, S2, S3	Catphan 600, low‐contrast resolution module
Transverse spatial resolution and modulation transfer function MTF (Fig. 4)	120 kV, 200/50 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, 2 mm slice thickness, pitch 1.0	FBP: B70s SAFIRE: I70h S1, S3, S5	Catphan 600, high‐resolution module
Coronal spatial resolution (Fig. 5)	120 kV, 500 mAs, 1.0 sec rotation time, $128\times 0.6\text{mm}$ collimation, pitch 1.0	FBP: B46f SAFIRE: I46f S5 MPR: 1 mm recon thickness, 0.1 mm image increment	3D spatial resolution phantom