ObjectiveTo investigate the application value of superb microvascular imaging（SMI） and Power Doppler ultrasound（PDUS）in monitoring synovium blood flow in finger and wrist joints with rheumatoid arthritis（RA）in clinical remission.MethodsThe bilateral wrist

metacarpophalangeal joint and proximal phalangeal joint of 40 RA patients in clinical remission and 20 healthy volunteers were examined by ultrasound.The blood flow grading results of PDUS and SMI on thickened synovial membrane were recorded.The difference of synovial blood flow and its classification between the two methods was observed

and the consistency of the results of synovial blood flow classification between the two methods was compared.ResultsIn the 40 patients with RA in clinical remission

PDUS showed blood flow signal in synovium of joint in 16 patients

the remission rate was 60%（24/40）

SMI showed blood flow signal in synovium of joint in 25 patients

the remission rate was37.5%（15/40）

there was significant difference between the two methods（χ

2

=4.053

P=0.044）.In the 20 healthy volunteers

the detection rate of synovial blood flow by SMI and PDUS was 0.However

in the 40 patients with RA

the synovial blood flow display rates of SMI and PDUS were 12.72% and 8.64%

respectively

and the difference was statistically significant（χ

2

=7.718

P=0.005）.The results of synovial blood flow grading by PDUS and SMI were consistent by Kappa test（Kappa=0.741

P

<

0.01）.ConclusionIn the clinical remission stage of RA

SMI and PDUS both have great clinical application value

but SMI is more sensitive than PDUS in detecting the blood flow signal in the synovial membrane of finger and wrist joints.