Fig. 4

Quantitative analysis. a Recovered activity concentration in the tumor insert of the anthropomorphic phantom. Data are presented in terms of minimum and maximum recovered activity values, 1st and 3rd quartile, average activity concentration and recovered activity concentration after correcting for PVE. After the application of RCs, differences with measured activity concentration values reduce significantly with underestimations of the order of 4% down to an activity concentration of about 2 MBq mL⁻¹. b For each phantom acquisition HI_dDVH were plotted as a function of the number of positrons emitted from the VOI. A power function of the form y = ax ^b was used to fit data points, where x is the number of emitted positrons from the VOI and a and b coefficients to be determined from the fit. From the regression analysis it resulted b = − 0.54 ± 0.07 (with r ² = 0.86)