Three-dimensional functional images of myocardial oxygen consumption from positron tomography

Images from positron emission tomography (PET) are usually presented as transaxial slices portraying tissue radioactivity. Studies can be difficult to interpret from transaxial images, and the temporal changes in tissue tracer concentrations which permit quantitative determinations of metabolism and perfusion are not displayed. We have developed a method to give quantitatively accurate three-dimensional images of myocardial oxygen consumption from serial images of the myocardial washout of carbon-11-acetate. Following i.v. bolus injection, data are collected for 20-30 min. The time-activity curves for each pixel in the transaxial slices are fit to a monoexponential function to determine the washout rate, which is directly related to the rate of myocardial oxygen utilization. Thus, functional images of myocardial oxygen consumption are produced for all seven slices of PET data. A previously developed method is then used to generate realistic and quantitatively accurate three-dimensional images.