Real-time weighted integration system for rapid calculation of parametric rate-constant images in 3-dimensional positron emission tomography

A system has been developed to rapidly calculate functional images of parametric rate constants, without dynamic scan in 3D PET, and implementation of this system was tested in a clinical study following O-15 water administration. The technique is based on the weighted-integration algorithms derived for the 2- and 3-compartment models. The system consists of large-scale memory (1 GBytes) and a micro-processor that is capable of acquiring, transferring and making arbitrary arithmetic calculations during data acquisition, providing multiple time-weighted 3D-sinograms in real-time. These sinograms are reconstructed, and inserted into operational equations, thus generating parametric rate-constant images. This technique was found to reliably provide quantitative parametric rate-constant images in 3D PET, and thus would be useful for routine clinical use of 3D PET.