Quantitative power Doppler signal assessment in the subchondral bone region of the metacarpophalangeal joint is an effective predictor of radiographic progression in the hand of rheumatoid arthritis: a pilot study

Abstract

Objectives. To investigate the predictive value of the quantitative power Doppler (PD) signal assessment in the subchondral bone region of the metacarpophalangeal (MCP) joint concerning radiographic progression of the hand in patients with rheumatoid arthritis (RA) by comparing with those of the previously reported scoring systems. Methods. Twenty-two patients (20 women) with RA underwent power Doppler ultrasonography (PDUS) of the bilateral 1-5 MCP joints at baseline. Radiography of both hands was performed at baseline and at 1 year. PDUS of the synovial space was evaluated according to semi-quantitative scoring (0-3) and quantitative measurement (0-100%). The PD signal in the subchondral bone region was qualitatively (0, 1) and quantitatively (mm²) assessed. The performance of PDUS assessments were compared using the area under the curve (AUC) of the receiver operating characteristic curve and risk ratio (RR). Results. As a predictor for radiographic progression, the quantitative PD signal assessment in the subchondral bone region (AUC = 0.842, p < 0.01) was equivalent to quantitative vascularity (AUC = 0.817, p < 0.05), and better than semi-quantitative scoring (AUC = 0.754, p < 0.05). As for the RR of the PD signal in the subchondral bone region for radiographic progression, the quantitative PD signal assessment was 5.40 (p < 0.01), whereas the qualitative PD signal assessment was 1.60 (p = 0.204). Conclusion. Quantitative PD signal assessment in the subchondral bone region may predict radiographic progression of RA.