18F-FDG PET/CT in polymyalgia rheumatica-a pictorial review.

Polymyalgia rheumatica (PMR) is one of the inflammatory rheumatic diseases that can potentially be detected by positron emission tomography/CT. High fluorine-18 fludeoxyglucose (18F-FDG) accumulation around the shoulders, sternoclavicular and hip joints are the most common pre-treatment features of patients with PMR. Another common sign is increased 18F-FDG uptake in extra-articular regions between columnal spinous processes, near ischial tuberosities and in the praepubic area. Some patients also present with high 18F-FDG uptake in main arteries, corresponding to the characteristics of giant cell arteritis. It is possible to observe a decrease or even a disappearance of 18F-FDG uptake after effective therapy, an event which may be useful for the monitoring of treatment as well as for detection of PMR relapse.