We performed rapid sequential computerized tomography (CT) scanning following i.v. injection of a bolus of contrast medium, and generated three functional images related, respectively, to intravascular circulation time (rABCT), vascular volume density (Vv) and blood-brain barrier (BBB) unidirectional constant uptake rate (Ki). This was accomplished by calculating the first mathematical moment of the monitored time-density curves about the injection time, and by the multiple time graph analysis described by Patlack and coworkers. A satisfactory resolution was achieved, allowing separate appreciation of changes in rABCT both at large vessels and at tissue small vessels. Combined evaluation of rABCT and Vv images allowed us to draw qualitative conclusions about blood flow and perfusion reserve.