Diagnostic value of magnetic resonance imaging in early rheumatoid arthritis

Objective To investigate the diagnostic value of magnetic resonance imaging(MRI)of the wrist and finger joints in patients with rheumatoid arthritis(RA).Methods The study group comprised twenty-eight patients with newly diagnosed RA and sixty patients with early unclassified polyarthritis in whom erosions were not demonstrated on conventional radiographs.These patients underwent Gd-DTPA-enhanced MRI of wrist and finger joints to detect signs of arthritis at baseline.It was determined the presence of bone erosions,synovitis,joint effusion,tendonitis and bone marrow oedema.In a 1-year follow-up study,the patients with polyarthritis received clinical assessment.Results MRI revealed pathologic findings in the wrist and finger joints in 27 of 28(96%)newly diagnosed RA patients.After 1 year,24 of 60 patients with polyarthritis fulfilled ARA diagnostic standard,their disease duration(P=0.001),the number of swollen joints(P0.01),the number of tender joints(P0.01)and symmetry of wrist joints involve(P=0.046)were significantly different compared with 28 newly diagnosed RA patients at baseline,but MRI suggested abnormal in 96%(23/24)patients(synovitis in 22,bone erosions in 15,joint effusion in 8,bone marrow oedema in 6 and tendonitis in 14)already and had no significantly different compared with RA patients.MRI has been shown to be more sensitive than conventional radiography for detecting bone erosions in RA.Conclusion The data suggests that a high proportion of RA patients develop MRI erosions very early in their disease.MRI of the wrist and finger joints is a very valuable tool for assessment of both established and early RA,it contributes an additional method aimed at earlier and more accurate diagnosis and thus might allow an earlier decision to start appropriate medication in patients with early RA.