Parameters of the protocols used on the 320-row CT scanner
| Parameter | Noncontrast Head CT Scan (Volume) | Noncontrast Head CT (Incremental) | Combo (Cerebral CTA + CTP) | Neck CTA | |
|---|---|---|---|---|---|
| Infratentorial | Supratentorial | ||||
| Lens protection | No | No | Yes | Yes | |
| Collimation (mm) | 0.5 × 280 | 2 × 4 | 2 × 4 | 0.5 × 320 | 0.5 × 64 |
| Table increment (mm) | No | 8 | 8 | none | 20.5 |
| Pitch | 1 | 1 | no | 0.614 | |
| Tube current (mAseff) | 320 | 375 | 250 | 100 | Tube current modulation |
| Tube current (mA) | 320 | 250 | 100 | Tube current modulation | |
| Voltage (kV) | 120 | 120 | 80 | 120 | |
| Rotation time | 1 s | 1.5 s | 1 s | 1 s | 0.5 s |
| Scan length (mm) | 140 | 140 | 160 | 216 | |
| Scan time | 7.2 s | 26.8 s | 29.8 s | 30.99 s | |
| Gantry angulation | Yes | Yes | Yes | No | No |