动态增强MRI定量评价类风湿性关节炎腕关节炎症活动度的价值

The value of quantitative evaluation of infl ammatory activity by using wrist dynamic contrast-enhanced MRI in rheumatoid arthritis

目的探讨动态增强MRI(DCE-MRI)定量评价类风湿性关节炎(RA)炎症活动度的价值。材料与方法 20例经临床病理确诊的RA患者行双手腕关节DCE-MRI检查,滑膜病理Krenn评分、临床DAS28评分及血清学检查,运用动态增强专用血流动力学软件测量双腕关节滑膜病变区定量参数:容积转移常数(Ktrans)、速率常数(Kep)、血管外细胞外容积分数(Ve)、血浆容积(Vp)及半定量参数:达峰时间(TTP)、最大浓度(Cmax)、浓度-时间曲线下面积(AUC)、最大斜率(Slopemax),分析DCE-MRI定量及半定量参数与滑膜病理Krenn评分、临床DAS28评分及血清学检查各指标之间的相关性,采用t检验比较分析滑膜炎症不同活动度组间Ktrans值的差异。结果 20例RA腕关节滑膜病变Ktrans值为(1.27±0.59)ml/min,Krenn评分为3.38±1.53,DAS28评分为4.80±0.94。6例滑膜炎症为重度,11例滑膜炎症为轻度。Ktrans与Krenn评分、DAS28具有正相关(r=0.698,P<0.01;r=0.510,P<0.05),Kep、Ve、Vp及TTP、Cmax、AUC、Slopemax与Krenn评分、DAS28及血清学检查各指标之间无相关性(P>0.05)。滑膜炎症重度组Kt rans值明显高于轻度组(t=4.05,P<0.01)。结论 DCE-MRI的Ktrans值可用于反映RA患者临床及滑膜病变的炎症活动程度。

Objective： To investigate the value of quantitative evaluation of inflammatory activity by using wrist dynamic contrast-enhanced MRI（DCE-MRI） in rheumatoid arthritis（RA） patients. Materials and Methods： Twenty patients with clinically and pathologically proved RA underwent wrist DCE-MRI examination, Krenn scoring of synovial inflammatory, clinical scoring of DAS28 and serological examination. Quantitative parameters including the volume transfer constant（Ktrans）, rate constant（Kep）, extravascular extracellular volume fraction（Ve）, plasma volume（Vp） and semi-quantitative parameters including the time to peak（TTP）, maximum concentration（Cmax）, the area under concentration-time curve（AUC）, maximum slope（Slopemax） of wrist synovial lesions were derived from DCE-MRI data. Relationship between quantitative and semi-quantitative parameters and Krenn scores of synovial infl ammatory, clinical score of DAS28 and serological results were analyzed by using correlation analysis. Ktrans values between different grades of synovitis were analyzed by using Student t test. Results： The average Ktrans value of 20 patients was（1.27 ± 0.59） ml/min, the average Krenn score was 3.38 ± 1.53, and the average DAS28 score was 4.80 ± 0.94. Pathologically, six patients had high-grade synovitis and eleven patients had low-grade synovitis. Positive correlation was found between Ktrans and Krenn scores, as well as between Ktrans and DAS28 scores（r=0.698, P〈0.01; r=0.510, P〈0.05 respectively）. However, no correlation was found between Kep, Ve, Vp, TTP, Cmax, AUC, Slopemax and Krenn scores, DAS28 scores, serological results（P〉0.05）. Ktrans values in highgrade synovitis group were higher than these in low-grade synovitis group（t=4.05, P〈0.01）. Conclusion： Ktrans values derived from DCE-MRI can be used to refl ect the clinical and pathological infl ammatory activity of RA.