Gadolinium-enhanced magnetic resonance imaging in shoulders contributes accurate diagnosis and predicting recurrence to patients with polymyalgia rheumatica.

Objectives We aimed to evaluate whether gadolinium-enhanced magnetic resonance imaging (MRI) in shoulders can contribute to more accurate diagnosis and prediction of recurrence in patients with polymyalgia rheumatica (PMR). Methods Gadolinium-enhanced MRI and ultrasonography (US) in shoulders were performed in the patients who had bilateral shoulders pain and fulfilled the Bird's Classification Criteria between June 2012 and June 2018. PMR was clinically diagnosed by at least two rheumatologists. MRI and US findings assessed by independent radiologists were compared between the PMR or non-PMR patients. PMR patients were treated with 20 mg/day of prednisolone and were followed-up until June 2019 to determine any recurrences of the disease. Results PMR was diagnosed in 58 of 137 patients received gadolinium-enhanced MRI and US examinations. Enhancement of joint capsule, enhancement of rotator cuff tendon and focal bone oedema in humerus heads were frequently found in the PMR patients. If the three findings were used in combination to diagnose PMR, MRI had 76% sensitivity and 85% specificity, higher compared to US findings, which had 50% sensitivity and 72% specificity. During follow-up, PMR recurred in 24 patients. Patients with recurrent PMR were younger in age, had less enhancement of rotator cuff tendon and more synovial hypertrophy findings on their MRI. Conclusions Gadolinium-enhanced MRI could display capsulitis, rotator cuff tendonitis and focal bone oedema in humerus heads that was sensitive and specific to patients with PMR, improving diagnostic accuracy in PMR. Rotator cuff tendonitis and synovial hypertrophy on MRI could help predict recurrence in PMR.