PET/CT Imaging of Mouse Models

For the PET/CT experiments, mice were fasted for 12 h before radiotracer injection and anesthetized with xylazine (10 mg/kg) and ketamine (100 mg/kg) through intraperitoneal injection prior to radiotracer administration. Subsequently they were injected via the lateral tail vein with approximately 22.2 MBq of [¹⁸F]F-FDG or 5.55 MBq of [⁶⁴Cu]Cu-DOTATATE. Tracers were allowed to circulate for 60 min. Immediately before imaging, mice were placed under 1% isoflurane (BaxterHealthcare, Deerfield, IL), and subsequently imaged on a high resolution (700 µm) Mediso nanoScan PET/CT scanner (Mediso, Budapest, Hungary). CT scan was acquired at 50 kVp and 300 ms exposure per projection. eXIA160 (Binitio, Ontario, Canada) was used as a contrast agent to improve imaging of the vasculature by intravenous administration of 100 μl per mouse 5 min prior to CT acquisition^{51 (link)}. PET acquisition time was 40 min. Reconstruction was performed using TeraTomo 3D reconstruction engine, for 8 iterations and 6 subsets per iteration for both tracers. The voxel size was isotropic at 0.3 mm. Immediately after the PET/CT scan, animals were euthanized for ex vivo assays.