Assessment of PET scanner quantitative factors: Analysis and validation of GATE Monte Carlo simulation with experimental study

Author(s): Mehrnoosh Karimipourfard, Sedighe Sina*, M. Sadeghi, R. safari & M.S. Alavi

The quality control procedure would also be a requirement for any department to achieve a level of formal accreditation. The QC of the PET images was performed using NEMA and Jaszczak phantoms. This article describes the experimental and simulation quantitative protocols of acquiring PET imaging parameters to validate and analyze the result to use in complex geometry, patient dosimetry, and the optimal value of scanner performance in comparison studies. The QC factors such as signal-to-noise ratio, SNR, contrast to noise ratio, CNR, standardized uptake values, SUV, and spatial resolution were estimated from the hot and cold PET-CT images of the phantoms containing various activities. GATE Monte Carlo code was used for simulation of the phantoms. The images were reconstructed by STIR software, and the QC parameters of the simulation-based images were obtained. The maximum differences between SNR results of the Monte Carlo simulation, and the experimental results were found to be 2.29 and 2.93, and the maximum differences in CNR values were reported to be 2.79 and 2.2 for 20 and 40 MBq/ml activates respectively. The spatial resolution of the images was obtained by the size of spheres and rods of the Jaszczak phantom. According to the results 12.7 and 15.9 mm sphere diameters and 8 mm rod diameters were invisible in 20 and 40 MBq/ml cold scans. The simulation results show that the GATE Monte Carlo code is a beneficial tool for the simulation of PET images. These findings, while preliminary, suggest that analyzing the factors in patient dosimetry with a relation of the pixel intensity value of images with activity variation.