We annually evaluated (18)F-fluorodeoxyglucose-positron emission tomography/ computed tomography (FDG-PET/CT) scans for three consecutive years in a patient with rheumatoid arthritis. The inflammatory activity of the rheumatoid synovium was visualized in coronal and transverse sections by FDG-PET/CT. The extent and area of the synovial inflammation was relatively well delineated, and this technique was more informative in detecting inflammation than were conventional X-rays.