Takaki M, Takenaka N, Mori K, et al. - Researchers sought the optimal standardized uptake value (SUV) cut-off values using 18F-FDG positron emission tomography (PET) computed tomography (CT) to visualize the infection focus of osteomyelitis accurately. Initially, a case was examined where bacteriological detection of osteomyelitis was done after orthopedic surgery on the lower limb. They investigated the optimal SUV cut-off value of the 18F-FDG PET/CT image taken before surgery based on the surgical pathology. They examined the decided SUV cut-off value for its accuracy for diagnosing osteomyelitis. 18F-FDG PET/CT was performed on a total of 16 patients for suspected osteomyelitis (one case involved the upper extremity and 15 cases the lower one). Surgery was undertaken in all these patients. Bacteriologic culture of surgical specimens and histopathologic analysis were undertaken for making the final diagnosis. Surgical pathology was compared with preoperative 18F-FDG PET/CT. In the first case studied, the most accurate localization of infection was done with a SUV with a lower level of 2.00 and an upper of 8.00. The SUV was set with a lower level of 2.00 and an upper level of 8.00 following comparison of the pathological findings with the 18F-FDG PET/CT. They detected infection with positive pathological findings in 13 cases. In these cases, high accumulation was observed in preoperative 18F-FDG PET/CT. They identified no infection using pathological findings or 18F-FDG PET/CT findings in the remaining three cases. These findings suggest that accurate visualization of the infection focus of osteomyelitis could be done by setting the SUV cut-off lower level to 2.00 and upper level to 8.00. This 18F-FDG PET/CT technique is thus suggested to be valuable for image-guided surgery of osteomyelitis.