Cerebral Blood Flow with the Continuous Infusion of Oxygen-15-Labeled Water

This work describes the determination of CBF in eight normal human subjects with positron emission tomographic (PET) imaging using the continuous intravenous infusion of H215O. A whole-brain CBF model is described that permits the comparison of the CBF values determined using PET with those obtained using other methods. This model includes a correction for whole-brain recovery coefficient, a correction for the underestimation of flow due to the nonlinearity of the CBF model when considering tissue that includes both gray and white matter, the use of in vitro-determined brain–blood partition coefficients for gray and white matter, and a variation of the equilibrium model that permits the arterial concentration to vary. CBF values using this method compare well with values determined previously. Regional determinations using a brain overlay atlas are presented. Radiation dosimetry for the continuous infusion of H215O is also included.