MRI Scoring Test for Hand RA Now Extends to Joint Space Narrowing

A scoring system using MRI to evaluate the status of joints in patients with rheumatoid arthritis (RA) has now been extended to another aspect of joint damage, researchers report at the 2013 annual meeting of the European League Against Rheumatism (EULAR) in Madrid, Spain. The OMERACT-RAMRIS system now matches the reliability of computed tomography (CT) for measuring joint space narrowing (JSN) in the hand.

This is significant, as CT provides optimal imaging of bone surfaces, and a scoring system based on CT is regarded as the standard reference for assessing JSN.  

The new JSN scoring system in rheumatoid arthritis, one step in  an effort to determine whether OMERACT-RAMRIS can be implemented in clinical practice, is part of the international Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) initiative. Previous assessments have validated the scoring system using MRI to assess edema, erosion volume, and synovitis in RA of the hand.

This small study compared MRI, CT, and X-ray images of the wrist and metacarpal from 14 RA patients and one healthy control.The images came from a clinical trial, representing a broad range of JSN on X-ray, and were assessed twice independently for JSN by three readers. X-rays were scored by a single reader using the Sharp-van der Heijde method.

The analysis found high agreement between MRI and CT imaging, according to lead investigator Uffe Mller Dhn MD and coworkers in the Department of Rheumatology at Copenhagen University Hospital. X-ray images agreed only moderately with those from CT.