NEMA-2008 and In-Vivo Animal and Plant Imaging Performance of the Large FOV Preclinical Digital PET/CT System Discoverist 180

The RAYCAN Discoverist 180 (RAYCAN D180) is a novel preclinical positron emission tomography (PET) and computed tomography (CT) integrated system for the imaging of small- and medium-sized animals and plants. We measured a system resolution of (2.56 ± 0.04) mm (radial), (2.46 ± 0.05) mm (transverse), and (1.67 ± 0.03) mm (axial) at the center of the field of view using a filtered backprojection reconstruction algorithm. An OSEM-PSF-3D reconstruction algorithm improves the spatial resolution to (1.34 ± 0.04) mm (radial), (1.35 ± 0.05) mm (transverse), and (1.64±0.04) mm (axial). The peak noise equivalent count rate of the system is (713 ± 2) kcps, (207 ± 2) kcps, and (47 ± 1) kcps reached at approximately 97 MBq for the mouse-, rat- and monkey-like phantoms, respectively. This result is approximately 2x higher and is reached at approximately 3x higher activity in comparison with most of the existing commercial and research scanners. The peak absolute system sensitivity is (4.00±0.02)% and is competitive with state-of-the-art preclinical PET scanners. We found an image uniformity of (4.86±0.04)%. Finally, we report the static PET/CT scan of a mouse and of a leaf of Epipremnum aureum, and the time-activity curves of the [18F]-FDG metabolism in mouse left myocardial ventricle and kidneys obtained with a PET/CT scan in dynamic modality.