Functional circulation and blood-brain permeability images by angio CT in the assessment of cerebral ischemia

Abstract We performed rapid sequential computerized tomography (CT) scanning following ii.v. injection of a bolus of contrast medium, and generated three functional images related, respectively, to intravascular circulation time (rABCT) vascular volume density ( V v ) and blood-brain barrier (BBB) unidirectional constant uptake rate ( K i ). 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 V i images allowed us to draw qualitative conclusions about blood flow and perfusion reserve.