Nuclear Medicine Seminars, cilt.8, sa.1, ss.43-58, 2022 (Scopus)
Diagnosis and treatment of bone and soft tissue infections are more difficult than other infections. Since there is no single specific diagnostic method, a multidisciplinary approach is required in which clinical, laboratory, microbiological/histopathological and imaging methods are used together. Direct radiographs, computed tomography (CT) and magnetic resonance imaging are radiological methods used in diagnosis and provide diagnostic benefit through anatomical changes. Radionuclide imaging, on the other hand, allows functional and metabolic evaluation and early detection of the disease before anatomical changes occur. The main nuclear medicine methods used in musculoskeletal infections are three-phase bone scintigraphy (TPBS), Gallium-67 (Ga-67) citrate scintigraphy, and labeled leukocyte scintigraphy (LLs). Each test has some limitations. Although TPBS is a sensitive test, it has low specificity, especially in the presence of underlying bone anomalies. Ga-67 citrate has a long injection-imaging interval and may show false positive uptake in cases of tumor, trauma, and aseptic inflammation. It is primarily preferred in spine infections. LLs is the first preferred imaging method in cases of complicated osteomyelitis except spinal infections. However, it is a laborious process that requires equipped personnel-environment and sterility, and it should be evaluated together with bone marrow scintigraphy for optimal diagnosis. Although new alternative in vivo labeling methods such as labeled antigranulocyte antibodies and antibody fragments have been investigated, they have not been used routinely due to some limitations. In recent years, with the combination of these conventional methods with single photon emission computed tomography (SPECT/CT) and the introduction of 2-F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET/CT), significant improvements in diagnostic accuracy and reliability have been achieved. SPECT/CT allows the correct anatomical localization of the involvement area, accurate detection of the spread of infection, and especially the differentiation of bone-soft tissue infections. FDG PET/CT has high sensitivity and negative predictive value, especially in the diagnosis of spinal infections. It also has high diagnostic sensitivity in patients with metallic implants. Although it is also used in diabetic foot infections, its effectiveness is lower. Its use is also increasing in skull base osteomyelitis. Studies are still ongoing to develop more specific new PET pharmaceuticals such as Ga-68 citrate, 6''-F-18 fuoromaltotriose, F-18 F-p-Aminobenzoic acid (F-PABA) and iodine-124 fialuridine (I-124 FIAU).