Evaluation of the activity of synovitis in patients with rheumatoid arthritis: Value of power Doppler ultrasonography

To correlate the grades on power Doppler ultrasonography with clinical disease activity indices and acute phase reactant values for assessing the activity of synovitis in patients with rheumatoid arthritis. Twenty patients with rheumatoid arthritis diagnosed on the basis of American College of power Doppler ultrasonography. Two experienced radiologists evaluated, in consensus, the power Doppler signals as follows: grade I=no flow or minimal flow, grade 2=mild flow, grade 3=moderate flow and grade 4= marked flow. The clinical disease activity indices consisted of the counts of tender joints and swollen joints, patient's assessment of pain, patient's global assessment of disease activity, physician's globe assessment of disease activity and patient's assessment of physical function. Acute-phase reactants included CRP and ESR. The grades on power Doppler ultrasonography were correlated with clinical disease activity indices as well as acute-phases reactant values by a use of Spearman rank correlation coefficient. The grades on power Doppler ultrasonography showed a statistically significant correlation with tender joint count (rs=.835; p<.05), swollen joint count (rs=.833; p<.05), physician's global assessment of disease activity (rs=.857; p<.05), CRP (rs=.838; P<.05) and ESR (rs=.838; p<.05). The power Doppler ultrasonography is an useful diagnostic modality for assessing the activity of synovitis in patients with rheumatoid arthritis.