New insights into the role of imaging in polymyalgia rheumatica

PMR is an inflammatory rheumatic disease of elderly people characterized by pain and stiffness in the neck, shoulder and pelvic girdles. No specific diagnostic confirmatory tests exist and clinical symptoms, as well as increased acute phase reactants, are unspecific. The diagnostic value of imaging including ultrasound, MRI and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) with/without CT for PMR is increasingly studied. These techniques, particularly FDG-PET/CT, may help to detect underlying GCA in PMR patients with an incomplete response to glucocorticoids and/or recurrent relapses. Recent imaging studies provide novel insights into the anatomical basis of inflammation in PMR, particularly at hip and spine, which may help to distinguish this disease from other mimicking conditions. In this review, we discuss novel insights into the pathoanatomy of PMR, compare the diagnostic values of different imaging techniques and summarize current data on the role of imaging for monitoring and outcome prediction.