Limits and perspectives of ultrasound in the diagnosis and management of rheumatic diseases

Abstract

Musculoskeletal sonography (MSUS) has played a growing role in the diagnosis and management of rheumatic diseases, enabling the imaging of synovitis, bone erosion, and cartilage damage in the early phase of arthritis. "Dynamic" evaluation of tendons and help in guiding needle positioning in interventional manoeuvres are some of the other reasons for its success. MSUS, particularly when coupled with power Doppler (PD) examination, has recently been shown to be an efficient tool for monitoring disease activity and progression in rheumatoid arthritis, spondyloarthritis, crystal-related arthropathy, and osteoarthritis, with general consensus on its interesting results. More specifically, the PD signal has proved to be a simple and promising tool for short-term monitoring of synovial vascularity changes induced by steroids or biological agents in RA patients. MSUS has some limits, because of the physical properties of US and the quality of the equipment; it is, moreover, an operator-related imaging technique, with few standardized protocols. Future goals should be standardization of the examining approach in grey scale and Doppler ultrasound (US), including use of new equipment (3D US), extensive use in other fields (i.e. connective tissue diseases and vasculitis), and possible new applications (e.g. thoracic US).

Power Doppler ultrasonography of symptomatic rheumatoid arthritis ankles revealed a positive association between tenosynovitis and rheumatoid factor

“…The ability of PDS to reveal synovial inflammatory activity in rheumatoid hands was reported to be comparable to that of post-contrast high-field MRI [22] and superior to that of low-field MRI without contrast [23]. More specifically, PDS has proved to be a simple and promising tool for short-term monitoring of synovial vascularity changes induced by steroids or biological agents, including infliximab, etanercept, and adalimumab, in RA patients [13]. An analysis of interobserver variation in diagnoses based on PDS data also produced encouraging results [24].…”

“…The definitions based on BUS basically conformed to the OMERACT 7 consensus [27] and were modified with reference to recent reviews [13,28]. Joint synovitis was defined as synovial fluid collection (anechoic or hypoechoic, compressible homogenous joint space widening) and/ or synovial proliferation (homogenous, noncompressible, echoic joint space widening).…”

“…Synovial proliferation and effusion are accurately distinguished, and, in some joints (e.g., finger joints), synovitis can be visualized with higher sensitivity in US than in MRI [12]. Furthermore, US is now considered the gold standard for the evaluation of pathological changes in tendons [13]. Its effectiveness in the diagnosis of foot diseases, however, is less securely established.…”

Clinical assessment and outcome research in spondyloarthritis

“…A disadvantage of US is that it does not appropriately image very deep structures, such as the spine and SI joints, which are commonly affected in SpA [35]. However, this may be due to the technique used.…”

“…Furthermore, US can be used for guided aspiration of synovial fl uid or corticosteroid injection. In combination with power Doppler examination, which shows hyperemia that can be considered as an indirect sign of infl ammation, US has been shown to be an effi cient tool for monitoring disease activity, progression, and response to treatment in SpA [33][34][35]. US examination is cheap, safe, widely available, and comfortable for patients, and multiple joints can be assessed in one setting.…”