Post Mortem Leukocyte Scintigraphy in Juvenile Pigs with Experimentally Induced Osteomyelitis

We have previously demonstrated that (111)In-labeled autologous leukocyte scintigraphy is able to detect osteomyelitis in living juvenile pigs. In animal research studies, it may well be an advantage if the animals could be scanned after euthanasia. Applying traditional scanning of living animals to euthanized animals will render anaesthesia unnecessary and be ideal for obtaining good and reliable scans for the correct interpretation of imaging afterwards, since the animals do not move. The autologous leukocytes of the pigs were collected, marked with (111)In, and reinjected into the pigs and allowed for homing to the site of infections as usual while the pigs were alive. In this study, we demonstrate that it is possible to perform SPECT/CT with (111)In-labelled autologous leukocytes almost 24 hrs after euthanasia with the same detectability of osteomyelitic lesions as in living pigs (78% versus 79%). The pigs in this study had exactly the same experimental conditions as the living pigs and were examined in parallel with the living pigs except for euthanasia prior to the leukocyte scan and that no PET/CT scans were performed.