QUANTITATION OF REGIONAL CEREBRAL BLOOD-FLOW WITH O-15-BUTANOL AND POSITRON EMISSION TOMOGRAPHY IN HUMANS

We describe the implementation and validation of a combined dynamic-au toradiographic approach for measuring the regional cerebral blood flow (rCBF) with O-15-butanol. From arterial blood data sampled at a rate of 1 s and list mode data of the cerebral radioactivity accumulated ov er 100 s, the time shift between blood and tissue curves, the dispersi on constant DC, the partition coefficient p, and the CBF were estimate d by least squares fitting, Using the fit results, a pixel-by-pixel pa rametrization of rCBF was computed for a single 40-s (autoradiographic ) O-15-butanol uptake image. The mean global CBF found in 27 healthy s ubjects was 49 +/- 8 ml 100 g(-1) min(-1). Gray and white matter rCBF were 83 +/- 20 and 16 +/- 3 ml 100 g(-1) min(-1), respectively, with a corresponding partition coefficient p of 0.77 +/- 0.18 and 0.77 +/- 0 .29 ml/g in both compartments. The quantitative images resulted in a s ignificantly higher gray matter rCBF than the autoradiographic images.