A5.02 Fluorescence optical imaging coupled with ultrasound radiography for detecting subtle hand inflammation in early rheumatoid arthritis

Objectives Fluorescence Optical Imaging (FOI) is an emerging modality that uses an intravenous fluorophore to display altered microcirculation (abnormal perfusion/capillary leakage) in synovial tissues in the hands. FOI can be analyzed visually (FOI-v) or by using automated Disease ACTivity (DACT). Using musculoskeletal ultrasound (MSUS) as a validated reference measure, we previously showed FOI to be highly sensitive and specific in detecting clinically manifest and silent synovitis in patients with various rheumatic diseases. Here, we analyze whether the same is true for early rheumatoid arthritis (eRA). Methods Hands and wrists ineRA patients were assessed by clinical examination, MSUS and FOI-DACT. Active inflammation was defined as having synovial-hypertrophy/effusions and intra-articular Doppler signaling on MSUS, and as increased optical-intensities on FOI-v. Scores on DACT ≥ 1 was considered indicative of disease activity. Results 39 eRA patients were studied [72% females, 56% previous/current smokers, 54% RF(+) and 69% ACCP(+)]. Of the 1326 joints in these patients, 303 were inflamed by clinical assessment, 380 by MSUS, and 400 by FOI-v. The percentages of patients and (mean ± SD) joints by clinical, MSUS and FOI-v were 69%(7.8 ± 8.1), 95%(9.7 ± 7.7), and 95%(10.3 ± 7.2), respectively. Using MSUS as reference, FOI-DACT was 95%(35/37) accurate in identifying patients with active disease, 24%(9/37) of whom had erosive RA. Good correlations noted between MSUS and FOI-v (rho = 0.803; p  Conclusions As reported for established rheumatic diseases, here we show high correlations and agreements between clinical examination, MSUS and FOI-v in detecting subtle inflammation in early RA as well. Moreover, DACT-FOI emerges as a useful automated quantitative scoring method for synovial inflammation in eRA. Reference Kisten Y, Gyori N, af Klint E, et al . 2015 Detection of clinically manifest and silent synovitis in the hands and wrists by fluorescence optical imaging. RMD Open . 1 : e000106. doi:10.1136/ rmdopen-2015-000106(http://rmdopen.bmj.com/content/1/1/e000106.full.pdf+html)