Diagnostic value of high-frequency ultrasound and magnetic resonance imaging in early rheumatoid arthritis

Early diagnosis and management improve the outcome of patients with rheumatoid arthritis (RA). The present study explored the application of high-frequency ultrasound (US) and magnetic resonance imaging (MRI) in the detection of early RA. Thirty-nine patients (20 males and 19 females) diagnosed with early RA were enrolled in the study. A total of 1,248 positions, including 858 hand joints and 390 tendons, were examined by high-frequency US and MRI to evaluate the presence of bone erosion, bone marrow edema (BME), synovial proliferation, joint effusion, tendinitis and tendon sheath edema. The imaging results of the above abnormalities, detected by US, were compared with those identified using MRI. No statistically significant overall changes were observed between high-frequency US and MRI in detecting bone erosion [44 (5.1%) vs. 35 (4.1%), respectively; P>0.05], tendinitis [18 (4.6%) vs. 14 (1.5%), respectively; P>0.05] and tendon sheath edema [37 (9.5%) vs. 30 (7.7%), respectively; P>0.05]. Significant differences were observed between high-frequency US and MRI with regards to the detection of synovial proliferation [132 (15.4%) vs. 66 (7.7%), respectively; P<0.05] and joint effusion [89 (10.4%) vs. 52 (6.1%), respectively; P<0.05]. In addition, significant differences were identified between the detection of BME using MRI compared with high-frequency US (5.5 vs. 0%, respectively; P<0.05). MRI and high-frequency US of the dominant hand and wrist joints were comparably sensitive to bone erosion, tendinitis and tendon sheath edema. However, MRI was more sensitive in detecting bone marrow edema in early RA, while US was more sensitive in the evaluation of joint effusion and synovial proliferation. In conclusion, US and MRI are promising for the detection and diagnosis of inflammatory activity in patients with RA.