[Comparative analysis of quantitative evaluation methods for FDG-PET scans]

The comparative analysis of two kinetic methods most frequently applied for the quantization of the results of FDG-PET brain scans was performed applying PET investigations and computer simulations. The analysis of the measured data and computer simulation demonstrated that the applicability of the results of SUV-methods to estimate glucose metabolic rates (GMR) as calculated by the Phelps-method (the most advanced method ) depended on the selected cerebral region. The distorted estimation was explained by the fact that the simpler models neglect dephosphorylation of the FDG-6P, and they also disregard the contribution of the intravascular activity to the tissue radioactivity. The simulations revealed the lack of a general and close positive correlation between SUV and GMR data; under special circumstances they might even change in an inverse manner.