All imaging data were processed with PMOD software (v3.1; PMOD Technologies Ltd., Zurich, Switzerland). MicroCT data were received from the Inveon platform as DICOM files and PET data as microPET files. Scans were imported into the program's local SQL database with the units for the PET radiotracer in kBq/ cc. PET images were co-registered with the CT images with reslicing done as necessary to facilitate later calculations. For analysis of 18F-FDG levels, the standardized uptake value (SUV) was used. SUV is a widely used semi-quantitative measure that normalizes radiotracer uptake in a given region of interest based on body weight, and calculated for this study as follows: 