Application of color Superb microvascular imaging and high-frequency ultrasonography in juvenile idiopathic arthritis

Objective To explore the application of color Super Microvascular Imaging (cSMI) and high-frequency ultrasonography (US) in evaluating the knee joint diseases of juvenile idiopathic arthritis (JIA) in the active period. Methods 90 patients diagnosed JIA clinically with knees pain and swelling were collected, the ultrasound diagnostic apparatus was used to examine knee joints. the main US signs were observed, the numbers of thickening of suprapatellar bursa synovial joints were recorded. The thickness of synovial membrane and the thickness of suprapatellar bursa effusion were also recorded, the blood flow signals of the thickening of synovial joints was checked by the cSMI and power doppler ultrasound (PDUS) separately. Color flow signals were graded by the semi-quantitative scoring systems. At the same period, the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were collected. The differences of cSMI and PDUS in thickened synovial blood flow were compared. The correlations between the parameters were analyzed. Results 110 suprapatellar bursa synovial joints showed synovial thickening, synovial thickened joints are associated with varying degrees of suprapatellar bursa effusion. The thickness of synovial membrane and the thickness of suprapatellar bursa effusion were (6.01±3.08) mm, (7.45±3.91) mm, respectively. The proportion of blood flow signals detected by cSMI in thickened synovial membranes of Wri was 86.36%, while that of PDUS was 59.09%. The differences of blood flow signals rate were statistically significant (P=0.000). The differences of grading of PDUS and cSMI were statistically significant (P=0.000), Compared with PDUS, cSMI can raise the blood flow classification level. PDUS and cSMI blood flow signals grading were positively correlated with CRP, ESR, synovial membrane and suprapatellar bursa effusion (P=0.000). CRP was positively correlated with ESR, synovial membrane and suprapatellar bursa effusion (P=0.000). Synovial membrane was positively correlated with suprapatellar bursa effusion (P=0.000). Conclusion The application of cSMI and High-frequency US is helpful in the early diagnosis of knee joint lesions in active JIA children. Key words: Juvenile idiopathic arthritis; Knee joint; Color super microvascular imaging; High-frequency ultrasonography