Performance evaluation of microPET P4 for rat, rabbit and monkey

Abstract MicroPET P4 is a Positron Emission Tomography (PET) scanner designed for small animal study with a 22-cm animal port and a 7.8-cm axial field of view (FOV). The scanner consists of 168 detector modules, each with an 8×8 array of 2.2×2.2×10 mm 3 lutetium oxyorthosilicate (LSO) crystals, arranged as 32 crystal rings with an inner diameter of 26 cm. The system operates in 3D mode and data acquisition is done in list mode. The object animals and target regions for ongoing microPET studies in this site were rat and monkey brains and rabbit lungs. The purpose of this study is to determine the attenuation effects of these objects. Three cylindrical phantoms with outer diameters of 3, 7 and 9 cm and simulated rat and monkey heads and rabbit thorax, respectively, were used for investigating the attenuation effects. The attenuation effects can be divided into “factor changing” (FC) and “increasing nonuniformity” (NU). The NU values were 10.2%, 31.8% and 42.5% in 3-, 7- and 9-cm phantoms, respectively. The FC values were −26.6%, −49.2% and −59.3% in 3-, 7- and 9-cm phantoms, respectively.