High accumulation of fluorine-18-fluorodeoxyglucose in turpentine-induced inflammatory tissue.

UNLABELLED Fluorine-18-2-deoxy-2-fluoro-D-glucose ([18F]FDG) uptake and distribution in an experimentally induced inflammatory tissue were investigated. METHODS Rats were subcutaneously inoculated with turpentine oil to induce inflammation and used for tissue distribution studies and autoradiography. RESULTS Time course study of [18F]FDG tissue distribution showed that the uptake in inflammatory tissue increased gradually until 60 min and then decreased. A longitudinal study of [18F]FDG tissue distribution showed that the uptake increased progressively to a peak 4 days after inoculation and then decreased. On the fourth day postinoculation, a section of inflammatory tissue showed characteristic changes of chronic inflammation. Macro- and micro-autoradiography showed a high density of silver grains in the abscess wall consisting of an inflammatory cell layer and granulation tissue. Grain counting on micro-autoradiography of the abscess wall showed that the highest grain density was found in the marginal zone of young fibroblasts, endothelial cells of vessels and phagocytes of neutrophils and macrophages, followed by that in the neutrophil layer and granulation tissue. CONCLUSION Our results indicate that [18F]FDG PET may be useful in detecting and monitoring chronic inflammatory processes.