[Evaluation of MRI in the diagnosis of rheumatoid arthritis].

Objective: to study the features of rheumatoid arthritis (RA) on MRI of hands and wrists and compare MRI with clinical manifestations and laboratory tests of RA.
Methods: a total of 25 patients fulfilling the 2009 ACR/EULAR RA criteria were enrolled. MRI and plain films of hands and wrists and clinical data of swollen joints, tender joints, visual scale (VAS) score, DAS28 score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), RF classification, anti-cyclic citrullinated peptide antibodies (anti-CCP antibodies) were obtained simultaneously.
Results: MRI revealed pathologic findings on the wrist and hand joints in all diagnosed RA patients. VAS had a positive correlation with bone marrow edema(r = 0.562, P = 0.003). Although the disease duration was less or more than 1 year, the difference of bone erosion had statistical significance between anti-CCP antibody-positive group and anti-CCP antibody negative group (all P = 0.000). The serum concentration of RF-IgA had a positive correlation with bone marrow edema (r = 0.561, P = 0.041). The synovitis score of MRI of RA was higher in the RF-IgG positive group than that in the RF-IgG negative group (P = 0.035). There was significant difference in MRI synovitis between the RF-IgG or RF-IgM positive and negative groups of patients with a disease course of under 1 year (P = 0.015, P = 0.007). The serum CRP level had a positive correlation with arthroderma (r = 0.457, P = 0.022).
Conclusion: MRI is proved to be a valuable examination for an early diagnosis and assessment of RA.