Table 1 Contrast media protocol and CT technical specifications
Parameter | 64-row CT scanner | 256-row CT scanner |
|---|---|---|
CM protocol | ||
Fixed dose protocol | 25 patients | 25 patients |
LBW protocol | 25 patients | 25 patients |
Scanner parameters | ||
Tube voltage | 120 kVp | 120 kVp |
Beam pitch | 1.375:1 | 1 |
Detector configuration | 64 rows × 0.625 mm | 2 × 128 rows × 0.625 mm |
z-axis tube current modulation | Smart mA, GE Healthcare | Dose Right ACS, Philips Healthcare |
Automatic mA current modulation | 200/600 mAs | 200/600 mAs |
Noise index | 28 | 22 DRI, Liver DRI of + 2 |
Slice thickness | 1.25 mm | 1.25 mm |
Spacing | 1.25 mm | 1.25 mm |
Iterative reconstruction | ASiR 40%; GE Healthcare | iDose4 – level 2; Philips Healthcare |