🩸 Vascular CT Protocols
Vascular imaging protocols including aorta, peripheral vessels, and runoff studies.
Quick Reference
| Clinical Scenario | Key Protocol Features | Timing |
|---|---|---|
| Aortic dissection | Arterial phase, non-gated | 25-30s |
| AAA evaluation | Arterial + delayed | 30s + 70s |
| Peripheral runoff | Multi-phase, bolus chase | Variable |
| Renal arteries | Arterial phase only | 20-25s |
Timing Optimization
Arterial Phase Timing
\[
\text{Delay} = \text{Circulation Time} + 5-8 \text{ seconds}
\]
Multi-Phase Protocols
- Arterial: 25-30 seconds
- Portal venous: 70 seconds
- Delayed: 180-300 seconds
Bolus Tracking
- Aortic arch: For head/neck CTA
- Descending aorta: For thoracic/abdominal
- Trigger: 150-200 HU
Common Pitfalls
- Early scan → poor arterial opacification
- Late scan → venous contamination
- Low flow rate → streak artifacts