Abstract
Introduction: Positron emission tomography (PET) using F-18 ßuorodeoxyglucose (FDG) is a promising new imaging modality for bone infections. The method is based on intensive cellular use of glucose during infection. The aim of the current study was to establish the FDG-PET characteristics of normal bone healing and bone infection under standardized conditions. Methods: A modiþed osteomyelitis model of Mader and Fitzgerald was applied in the rabbit (n=12). A metaphyseal defect of the proximal tibia was þlled with bone cement. A predetermined amount (0.1 ml) of Staphylococcus aureus (strain 52/52A/80, 1x105/ml) suspension was injected into the defect. The control animals received an equal saline injection without bacteria. Bone cement was removed from each animal at 2 weeks. During the follow-up, FDG-PET and pQCT were performed at 3 weeks and 6 weeks. Osteomyelitis was conþrmed with bacterial cultures at the time of cement removal and again at sacriþce at 6 weeks. Results: Compared with the contralateral intact tibia, control defects healing without infection showed an increased uptake (p=0.019) at 3 weeks but their FDG-PET tended to normalize within 6 weeks. In the osteomyelitis group, the uptake did not decrease over time and was signiþcantly (p< 0.001) increased both at 3 weeks and at 6 weeks compared with intact bone uptake. The uptake of the infected region was also signiþcantly higher than that of non-infected control defects. Conclusions: Standardized osteomyelitis of the current model was shown to result in an intense continuous FDG-PET activation, which is higher than the transient response of a healing bone defect.
Theses abstracts were prepared by Professor Dr. Frantz Langlais. Correspondence should be addressed to him at EFORT Central Office, Freihofstrasse 22, CH-8700 Küsnacht, Switzerland.
