Small Animal PET/CT Imaging Protocol

PET/CT imaging scans were performed on a small animal PET/CT scanner (Inveon PET/CT, Siemens Medical Solutions, Knoxville, TN, USA) according to a standard protocol as described before [30 (link)]. Briefly, mice were anesthetized by isoflurane (1–3%, supplemented with oxygen) and received a mean dose of 16.03 ± 1.10 MBq ^[18F]FDG intravenously via a microcatheter placed in a tail vein. Static PET scans were acquired using a small animal micro PET/CT scanner (Inveon PET/CT Siemens, Knoxville, TN, USA). The PET image reconstruction method consisted of a 2-dimensional ordered subset expectation maximization algorithm (2D-OSEM) with four iterations and six subsets. Attenuation correction was performed on the basis whole body CT scan and a decay correction for [¹⁸F] was applied. PET images were corrected for random coincidences, dead time and scatter. By marking the entire tumors, starting at the edge and cutting through the whole ^[18F]FDG-enriched tumor, volumes and SUVs were determined. This was done by using Inveon Research Workplace 4.2 software.