An evaluation of simultaneous dual-tracer technique for PET static studies

Simultaneous dual-tracer technique (SDTT) was proposed 30 years ago to discriminate between two PET radiotracer concentrations based on their different radioactive decay rates. This study evaluates the performance of SDTT in static studies using 2-deoxy-2-¹⁸F-fluoro-D-glucose (¹⁸F-FDG) and ¹³N-ammonium (¹³N-NH₄ ⁺) as radiotracers. SDTT was applied to a phantom. The influence of applying SDTT on either the reconstructed image or directly on the sinogram, different rebinning algorithms, total time acquisition and frame duration were investigated. Best results were obtained using the image method with a single-slice rebinning (SSRB) and total time acquisition of at least 20 min. Using the reasonable experimental settings better per-voxel statistics are achieved and subsequently SDTT has a better performance. Frame duration did not influence SDTT. The results encourage the use of SDTT as it has very good potential for simultaneously examining two different biological processes at the same time utilizing rodent PET scanners.