Toward Early Detection and Differentiation of Arthritic diseases: Quantification of Haemodynamics Changes in Small Joints

Inflammatory rheumatic diseases, such as rheumatoid arthritis (RA), are leading causes of disability and constitute a frequent medical disorder, leading to inability to work, high co-morbidity and increased mortality; RA involves indirect expenses secondary to disability, loss of productivity and early retirement. The gold-standard for diagnosing RA is based on patient conditions and radiographic findings, as joint erosions or decalcification. Recently, it has been shown that development of microvessels in the synovia is the earliest sign of RA, so that identification of prognostic factors such as persistent synovial hyperaemia is fundamental. By using immersion contrast-enhanced ultrasound with a steady probe to analyse the perfusion of those joints that are the most important for early detection of RA, we propose a quantitative analysis of the contrast kinetics in the synovial and peri-synovial tissues. This analysis allows the identification and differentiation of rheumatoid arthritis from other diseases that involve synovial activity such as psoriatic arthritis. We show the results of the proposed immersion-CEUS with a semi-automatic quantification procedure of the contrast kinetics in the synovia on a set of 16 metacarpophalangeal (MCP) joints of consecutive patients affected either by RA or psoriatic arthritis. Estimated kinetics parameters allows an accurate separation of the two classes of patients, that can be further improved by using serologic data.