Effect of detector scatter restoration on image spatial resolution and partial volume

The potential of positron emission tomography (PET) to provide quantitative physiological parameters in vivo is of great importance in medicine as well as in pharmacology. However, the PET data need to be previously corrected for the physical image degrading effects. In this work, we demonstrate the effect of detector scatter on image quality in small animal imaging as measured with individual crystals. PET scanners. The detector scatter is shown to affect the spatial resolution and the partial volume. Its effect on object scalier correction is also discussed. The spatial resolution was found to increase about 4% after restoration of detector scatter as assessed in the projections of the sinograms. The gain in amplitude of a small size measured structure corresponding to this ratio should be considered to subsequently accurately correct for partial volume effect.