Table 2:
Scan and reconstruction parameters for patient exams
| Chest | Temporal bone | Contrast-enhanced abdomen | Head CTA | ||||
|---|---|---|---|---|---|---|---|
| Modality | EID-CT | PCD-CT | EID-CT | PCD-CT | PCD-CT | PCD-CT | |
| Scanner platform | SOMATOM Force | SOMATOM Count Plus | SOMATOM Force | SOMATOM Count Plus | SOMATOM Count Plus | SOMATOM Count Plus | |
| Acquisition mode | Standard (single-energy) | UHR | UHR (comb-filter) | UHR | Standard (multi-energy) | Standard (multi-energy) | |
| Collimation (mm) | 192 × 0.6 | 120 × 0.2 | 64 × 0.6 | 120 × 0.2 | 144 × 0.4 | 144 × 0.4 | |
| X-ray focal spot size (mm2) | 0.8 × 1.1 | 0.6 × 0.7 | 0.4 × 0.5 | 0.4 × 0.5 | 0.8 × 1.1 | 0.8 × 1.1 | |
| Tube voltage (kV) | 120 | 120 | 120 | 120 | 140 | 140 | |
| Automatic Exposure (CARE Dose4D) | ON | ON | ON | OFF | ON | ON | |
| Tube current time product (mAs) | 80 (QRM) | 70 (QRM) | 400 (QRM) | 182 (effective) | 140 (QRM) | 150 (QRM) | |
| CTDIvol (mGy, size) | 5.3 (32 cm) | 5.3 (32 cm) | 49.9 (16 cm) | 31.6 (16 cm) | 11.7 (32 cm) | 16.1 (16 cm) | |
| Pitch | 1.2 | 1.2 | 0.35 | 1.2 | 0.8 | 1.2 | |
| Rotation time (s) | 0.25 | 0.33 | 1.0 | 1.0 | 0.5 | 0.33 | |
| Energy threshold (keV) | NA | 20 | NA | 20 | 20, 70 | 20, 70 | |
| Reconstruction technique | ADMIRE | PNR | ADMIRE | PNR | WFBP | PNR | PNR |
| Reconstruction kernel (IR strength) | Qr54 (3) | Qr76 (1,3) | Ur77 (3), Ur89 (3) | Hr76 (3), Hr89 (3) | Br44 | Br44 (1,3) | Qr40 (3) |
| Slice thickness (mm) | 0.6 | 0.6, 0.2 | 0.4 | 0.4 | 3.0 | 3.0 | |
| Slice increment (mm) | 0.5 | 0.5, 0.1 | 0.3 | 0.3 | 3.0 | 3.0 | |
| Reconstruction FOV (mm) | 340 | 340 | 80 | 80 | 380 | 250 | |
| Image matrix size | 1024 | 1024 | 512 | 512 | 512 | 512 | |
EID-CT: Energy-integrating detector-based computed tomography; PCD-CT: Photon-counting detector-based computed tomography; CTA: CT angiography; FOV: Field of view; CTDIvol: volume CT dose index; QRM: Quality reference mAs; IR: Iterative reconstruction; WFBP: Weighted filtered back projection; ADMIRE: Advanced modeled iterative reconstruction; PNR: Prior-based noise reduction