Recurrent surgical site infection of the spine diagnosed by dual ¹⁸F-NaF-bone PET/CT with early-phase scan

We report a case of a 31-year-old man who showed recurrently elevated level of the serum inflammatory marker C-reactive protein (CRP) after spinal operation. He underwent ¹⁸F-flurodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) and dual ¹⁸F-sodium-fluoride (¹⁸F-NaF) PET/CT with an additional early-phase scan to find a hidden inflammation focus. Only mildly increased ¹⁸F-FDG was found at the surgical site of T11 spine on ¹⁸F-FDG PET/CT. In contrast, dual ¹⁸F-NaF bone PET/CT with early-phase scan demonstrated focal active inflammation at the surgical site of T11 spine. After a revision operation of the T11 spine, serum CRP level decreased to the normal range without any symptom or sign of inflammation. Inflammatory focus in the surgical site of the spine can be detected with using dual ¹⁸F-NaF bone PET/CT scan with early-phase scan.