Introduction
CT perfusion provides rapid assessment of cerebral blood flow blood volume and mean transit time to estimate ischemic core and salvageable penumbra. It complements noncontrast CT and CT angiography in acute stroke triage. Timely acquisition and standardized postprocessing are essential for treatment decisions.
Acquisition and Processing
Dynamic contrast enhanced acquisition with appropriate temporal resolution is required to derive perfusion maps. Deconvolution algorithms and standardized thresholds are used to estimate core and penumbra volumes. Quality control for motion and contrast bolus timing affects reliability.
Clinical Integration
Perfusion results inform selection for thrombectomy and thrombolysis in extended time windows when clinical and vessel imaging are inconclusive. Interpretation must consider clinical presentation and collateral status on CTA. Multidisciplinary stroke teams integrate perfusion data with neurologic assessment for rapid decision making.
Limitations and Pitfalls
Perfusion maps can be affected by patient motion poor bolus and technical variability across vendors and software. Thresholds for core and penumbra are not universally standardized and require local validation. Continuous training and protocol harmonization improve clinical utility.