The validity of high-frequency Doppler ultrasound in identifying knees rheumatoid synovitis / 中华风湿病学杂志

ABSTRACT

ObjectivesTo examine the validity of high-frequency Doppler ultrasound in identifying knees synovitis in patients with rheumatoid arthritis(RA).MethodsNinety-five consecutive patients with active RA were examined withhigh-frequency Doppler ultrasound to examine synovitis signals in knees.Synovial tissue samples of 51 patients were obtained by closed needle biopsy from knees after ultrasound examination.Serial synovial tissue sections were stained with H&E and immunohistochemical staining,and the histopathological synovitis scores were evaluated.The relationship among clinical, histopathological and ultrasound synovitis indexes was analyzed by Spearman's rank order correlation test and receiver operating characteristic curve analysis.ResultsAmong 95 RA patients,the median thickness of synovial membrane in ultrasound was 2.8 mm,the median depth of effusion was 2.7 mm; Doppler signals of synovial blood flow were detected in 82％(78/95 ) of patients and the median semiquantitive grading of synovial blood flow was 1.0.The thickness of synovial membrane and synovial blood flow at Doppler ultrasound correlated positively with histological synovitis score,hyperplasia of the lining layer,and inflammatory infiltration in sublining area (the thickness of synovial membraner=0.438,0.424,0.368,respectively; synovial blood flowr=0.357,0.377,0.347,respectively; all P＜0.05).Although there was no significant difference in clinical synovitis indexes between patients with histologically low-grade and high-grade synovitis,the thickness of synovial membrane and synovial blood flow in ultrasound in patients with histologically high-grade synovitis was significantly higher than those with low-grade synovitis(P=0.001,0.036,respectively).When the thickness of synovial membrane in ultrasound was ≥ 3.9 mm,the specificity of diagnosing the high-grade synovitis was 96.7％ and the sensitivity was 61.9％.ConclusionSynovitis signals at high-frequency Doppler ultrasound correlate with histopathological synovitis,and it might be helpful in evaluating the severity of histopathological synovitis.