30-Second Review

CT Brain Perfusion

Contrast injection
↓
Repeated CT over time
↓
Contrast passage through brain
↓
Perfusion maps
↓
Core + Penumbra

Key Outputs

CBF
Cerebral Blood Flow
CBV
Cerebral Blood Volume
MTT
Mean Transit Time
TTP
Time to Peak
Tmax
Contrast arrival delay

Clinical Applications

NCCT
  • Bleed
  • Early ischaemia
CTA
  • Vessel assessment
  • Large-vessel occlusion
CTP
  • Perfusion
  • Core
  • Penumbra

Advantages

  • Quantitative perfusion maps
  • Distinguishes core from penumbra
  • Complements NCCT and CTA in acute stroke
  • Supports treatment selection

Limitations

  • Repeated acquisitions increase radiation
  • Coverage limited by detector size
  • Requires reliable contrast timing
  • Motion and artefact sensitivity
CT Perfusion = Contrast + Time + Brain perfusion → Core and Penumbra.