Utility of C-methionine and C-donepezil for imaging of induced osteomyelitis in a juvenile porcine model: comparison to autologous In-labelled leukocytes, Tc-DPD, and F-FDG.

The aim of this study was to compare C-methionine and C-donepezil positron emission tomography (PET) with In-labeled leukocyte and Tc-DPD (Tc-99m 3,3-diphosphono-1,2-propanedicarboxylic acid) single-photon emission computed tomography (SPECT), and F-fluorodeoxyglucose (F-FDG) PET to improve detection of osteomyelitis. The tracers' diagnostic utility where tested in a juvenile porcine hematogenously induced osteomyelitis model comparable to osteomyelitis in children. Five 8-9 weeks old female domestic pigs were scanned seven days after intra-arterial inoculation in the right femoral artery with a porcine strain of . The sequential scan protocol included Computed Tomography, C-methionine and C-donepezil PET, Tc-DPD and In-labelled leukocytes scintigraphy, and F-FDG PET. This was followed by necropsy of the pigs and gross pathology, histopathology, and microbial examination. The pigs developed a total of 24 osteomyelitic lesions, 4 lesions characterized as contiguous abscesses and pulmonary abscesses (in two pigs). By comparing the 24 osteomyelitic lesions, F-FDG accumulated in 100%, In-leukocytes in 79%, C-methionine in 79%, C-donepezil in 58%, and Tc-DPD in none. Overall, F-FDG PET was superior to In-leukocyte SPECT and C-methionine in marking infectious lesions.