Cerebral blood flow (CBF) is the blood supply to the brain in a given period of time. In an adult, CBF is typically 750 millilitres per minute or 15% of the cardiac output. This equates to an average perfusion of 50 to 54 millilitres of blood per 100 grams of brain tissue per minute.
| Term | Definition | Temporal Nature | Purpose | Example Tools |
|---|---|---|---|---|
| Cerebral Blood Flow Testing | One-time or episodic assessment of cerebral perfusion to answer a specific diagnostic question. | Snapshot / Single time point | Diagnosis or confirmation (e.g. brain death, no cerebral perfusion in TA-NRP) | CT/MR perfusion, radionuclide scan, transcranial Doppler (spot), angiography |
| Cerebral Blood Flow Monitoring | Continuous or repeated observation of cerebral perfusion over time. | Ongoing / Real-time or repeated | Trend analysis, intraoperative safety, critical care surveillance | Continuous TCD, cerebral NIRS, brain tissue oxygen sensors |
Key distinction: *Cerebral blood flow testing* provides a diagnostic snapshot. *Cerebral blood flow monitoring* tracks changes over time for clinical management.