ABSTRACT
Department of Nuclear Medicine & PET Research, VU University Medical Center, Amsterdam, the Netherlands
6.1 Positron emission tomography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 6.1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 6.1.2 Data normalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 6.1.3 Noise equivalent count rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 6.1.4 System dead time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108 6.1.5 Partial volume . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
6.2 Single photon emission computed tomography . . . . . . . . . . . . . . . . . . 112 6.2.1 Linearity, center of rotation, and whole body imaging . . 112 6.2.2 Motion correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
In PET a positron annihilation event results in two 511 keV photons. Due to conservation of momentum these photons are emitted in approximately 180-degree opposing directions. When detected as a prompt coincidence, the detectors in which the photons were detected define a so-called line of response (LOR; actually it is a tube of response, the volume of which is determined by the distance between the detectors and the area of the detector surface).
