Therapy efficacy evaluation in synovitis

Ultrasonography (US) allows a quantitative assessment of synovitis in patients with chronic inflammatory arthritis. US assessment of synovitis is essential for at least three reasons: (i) for diagnosing synovitis, (ii) for therapy monitoring, and (iii) for predicting relapse in patients in remission. A number of scoring systems, improving both reliability and responsiveness of US, have been proposed. In most of the published studies, grayscale and Doppler findings have been graded independently and each elementary component had its dedicated scoring system. However, there is still a lack of an expert-derived consensus, especially on the core set of joints to scan. Recently, the EULAR-OMERACT (European League Against Rheumatism-Outcome Measures in Rheumatology) group for musculoskeletal US has agreed on the use of a four-grade semiquantitative scoring system for both B-mode-detected and Doppler-mode-detected synovitis, which have demonstrated good multi-examiner intra-observer and inter-observer reliability in rheumatoid arthritis patients. The use of contrast-enhanced ultrasonography (CEUS) improves the sensitivity of Doppler US in the identification of abnormal vascularization in joint inflammation, allowing a better characterization of the pannus, in terms of differentiation between hypervascularity, hypovascularity, and avascularity.