BRAIN OXYGEN UTILIZATION MEASURED WITH O-15 RADIOTRACERS AND POSITRON EMISSION TOMOGRAPHY

  • 1 January 1984
    • journal article
    • research article
    • Vol. 25  (2) , 177-187
Abstract
A method for the measurement of the local cerebral metabolic rate for oxygen (CMRO2) with positron emission tomography (PET) was developed. Data from a single inhalation of O-15-labeled CO2 for cerebral blood volume (CBV), an i.v. injection of [O-15]H2O for cerebral blood flow (CBF) and a single inhalation of [O-15]O2 is used for the final calculation of CMRO2 and the extraction of oxygen (E). The mathematical model used to analyze the data consists of 2 compartments and accounts for production and egress of water of metabolism in the tissue, recirculating water of metabolism and the arterial, venous and capillary contents of [O-15]O2 in the brain. The technique was validated in baboons by comparing the PET-measured E with E measured using an intracarotid injection of [O-15]O2. The correlation between these 2 techniques was excellent. Mathematical simulations were done to examine the effect of errors in CBV, CBF and recirculating water of metabolism on the measurement of E and CMRO2. The technique was implemented on 5 normal human subjects in whom the global CMRO2 was 2.93 .+-. 0.37 (SD) ml/min.cntdot.100 g.