Recommended Acquisition Protocol for Perfusion-CT (PCT)
| Image acquisition rate | 2 phases: |
| 1st phase: 1 image per second, duration=30 to 45 seconds | |
| 2nd phase: 1 image per 2 to 3 seconds, duration=30 to 45 seconds | |
| Total duration of the acquisition at least 70 to 90 seconds | |
| Gantry rotation | 1 second per gantry rotation (up to every 3 seconds with “shuttle” or “toggle table” mode) |
| Image acquisition parameters | 80 kVp, 100 mAs |
| Coverage and slice thickness | Maximal coverage possible based on CT scanner configuration(minimal coverage of 20 mm slab per contrast bolus injection preferable; two boluses is suggested to double coverage for all CT scanners with under 4 cm detector length unless precluded by contrast dose considerations)focus on supratentorial compartment/anterior circulation5- to 10-mm-thick slicesfield of view ≈24 cm |
| Slice orientation | Parallel to hard palatelowest slice through the proximal middle/anterior cerebral artery (above the orbits) |
| Contrast material | 350 to 370 mg/mL iodinated contrast material high concentration, low/iso osmolar contrast preferred follow local guidelines for contrast-induced nephropathy prevention |
| Contrast volume | 35 to 50 mL, followed by 20 to 40 mL saline flush |
| Injection rate | 4 to 6 mL per second (power injector required) same injection rate for contrast and saline |
| IV access | 18 to 20 gauge IV lineright antecubital vein preferred (for anatomical reasons, reduces pooling of contrast, lowers the risk of extravasation and minimizes streak artifact at thoracic inlet in CTA portion) |
| Miscellaneous | PCT can be performed before or after CTA |