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A method of calculating brain blood flow with a CT dynamic scanner.

The development of CT scanners capable of making scans of short duration in rapid sequence offers the possibility of a noninvasive method of determining brain blood flow . The change in CT numbers in a series of such scans performed after the intravenous injection of a brief bolus of iodinated contrast medium clearly shows the passage of the bolus through the section being scanned . The additional prolongation of the bolus by its passage through the tissue can be observed . Because the change in CT numbers is proportional to the change in concentration of contrast, application of the principles of indicator-dilution analysis (1) with nondiffusible indicators permits, in principle, the calculation of regional blood flow within the cross section being scanned .