Search

Abstract: Objective: Computer-aided joint space analysis (CAJSA) is a newly developed technique for the measurement of radiogeometrically detectable joint space widths of the metacarpal-phalangeal (JSD-MCP) and proximal-interphalangeal articulations (JSD-PIP). The aim of this study was to verify the sensitivity and specificity of these CAJSA measurements in the assessment of established RA. Methods: Four hundred and fifty-eight participants (248 healthy subjects, 210 RA patients) underwent computerized semi-automated measurements of the JSD-MCP and JSD-PIP articulations (CAJSA, Radiogrammetry Kit, Version 1.3.6) based on digitally performed radiographs. The Sharp joint space narrowing score was also performed to determine RA-related joint space narrowing. Results: The significant severity-dependent reduction for JSD-MCP was –44.0% and for JSD-PIP, –25.94% between Sharp scores 0 and 3. The sensitivity and specificity of JSD-MCP (total) was 88.1% versus 77.8%, respectively (AUC=0.920; P <0.001). Furthermore, JSD-PIP (total) revealed a lower sensitivity and specificity with 61.4% and 88.7% (AUC=0.878; P <0.001). Conclusion: The CAJSA method presented a reliable assessment of disease-related joint space narrowing in patients suffering from RA with excellent sensitivity and specificity. By providing quantitative data, other scoring methods could be significantly improved, and thereby the accuracy of the diagnosis and a better therapeutic evaluation could be achieved. [Copyright &y& Elsevier]

Abstract: Objectives: Computer-aided joint space analysis (CAJSA) is a recently developed, semi-automated tool to aid in the measurement of joint space margins based on hand radiographs. The objective of this study is to verify the potential effect of hand rotation during X-ray imaging on the measurement of joint space width using CAJSA and to evaluate the reproducibility of the CAJSA technique in healthy subjects and in patients with rheumatoid arthritis. Methods: All joint space distance (JSD) measurements were performed using CAJSA-technology at the metacarpophalangeal articulation based on conventional and digital hand radiographs. Results: I. Hand rotation showed an effect on the reproducibility with CV ranging between 0.39% (angulation 1°) and 1.66% (angulation 19°). II. Regarding the overall reproducibility of the CAJSA method, the intra-radiograph reproducibility of JSD was calculated with CV=0.54% for conventional images and CV=0.38% for digital images. The inter-radiograph reproducibility error was observed with CV=0.66% (conventional images) and CV=0.63% (digital images). III. The study revealed a reproducibility for CAJSA measurements in RA ranging between 0.37% (JSD-MCP ring finger; van der Heijde-modification of the Sharp method Score 1) to 1.37% (JSD-MCP index finger; van der Heijde-modification of the Sharp method Score 3). Conclusion: CAJSA measures JSD at the metacarpophalangeal articulation with high reproducibility in healthy subjects and in patients with differing stages of rheumatoid arthritis. Additional findings show that hand rotation during X-ray imaging has an impact on the CAJSA measurements; thus avoiding acquisition of hand radiographs with a rotation error of more than 15 degrees can be recommended. [Copyright &y& Elsevier]