To provide the qualitative and quantitative characteristics of changes revealed by the data of magnetic resonance imaging (MRI) of the hand and by those of X-ray study of the hand and foot in patients with early rheumatoid arthritis (ERA).
The study enrolled 110 patients (90 females, 20 males; age 49.6 +/- 12.2 years) examined in the framework of the RADICAL program at the Research Institute of Rheumatology, Russian Academy of Medical Sciences. The mean duration of the disease was 5.61 +/- 3.17 months. The diagnosis of rheumatoid arthritis was established by the 1987 ARA criteria in all the patients on primary standard examination comprising X-ray study of the hand and feet and evaluation by the modified Sharp method. MRI of the hand was performed in all the patients, by assessing the result by the OMERACT-RAMRIS procedure.
Destructive changes (cysts and erosions) evidenced by X-ray study were found in the wrists, metacarpophalangeal articulations (MPA), and foot in 7.27, 8.2, and 13.64%, respectively. MRI revealed destructions in the wrist, MPA, and metacarpal bone base in 50, 60, and 16.36%, respectively. Overall, erosions could be seen on X-ray films and MRI scans in 20.91 and 67.27%, respectively (p < 0.0001). MRI revealed bone edema (osteitis) in 46.4% of the patients; there was no difference in the detection rate between the extremities. MRI synovitis was found in 99% of the patients, the right hand being significantly more commonly affected. Detailed characterization of the changes revealed by MRI and Xray was obtained in patients with ERA.
MRI detected erosions significantly more frequently than did X-ray (p < 0.001), which confirms the high value of low-field MRI diagnosis on primary examination of patients with ERA and supports the opinion that the results of this study should be included into the diagnostic criteria of ERA.