The Siemens Inveon multimodality PET/CT imaging scanner is capable of providing three dimensional CT and PET images of live mouse and rat as well as fixed samples. The system can deliver high resolution CT images (<10 µM for a field-of-view <20mm) with a maximum field-of-view of 80 mm X 50 mm (with a resolution of approximately 50 µM). The minimum resolution achievable with the PET scanner is approximately 1 mm (maximum field-of-view of 120 mm) with a high sensitivity in pico-Molar range. The PET scanner uses molecular imaging probes labelled with positrons-emitting radionuclides produced by a cyclotron (i.e. 18F, 11C, 64Cu).