Fig. 7

Ratio between mean concentration in the threshold-based VOIs (40% and 50% of maximum voxel value) and actual concentration and volume of these VOIs for the QSPECT reconstruction (a, b), the fQSPECT reconstruction (c, d) and the Bayesian reconstruction (e, f). Data for VOIs based on 40% and 50% of the maximum voxel value are indicated by solid and open symbols, respectively. The dashed lines in a, c, e indicate a ratio of unity, while in b, d, f they represent the lines of identity and the dash-dotted lines indicate the volume of a ø20 sphere. The solid lines indicate the fit of Eq. (5) for the 40% of maximum value method