Isotope independent determination of PET/CT modulation transfer functions from phantom measurements on spheres

A PET/CT system's imaging capabilities are best described by its point spread function (PSF) in the spatial domain or equivalently by its modulation transfer function (MTF) in the spatial frequency domain. Knowing PSFs or MTFs is a prerequisite for many numerical methods attempting to improve resolution and to reduce the partial volume effect. In PET/CT, the observed PSF is a convolution of the system's intrinsic imaging capabilities including image reconstruction (PSFPET/CT images of seven phantom spheres with volumes ranging from 0.25 to 16 ml and filled either withThe MTF fit method was able to determineMTF