关节滑膜巨噬细胞的超顺磁性氧化铁粒子增强MRI实验研究  

An experimental study of SPIO enhanced MRI of articular synonvial macrophage

作　　者：方挺松[1] 彭加友[1] 黄钰坚[1] 许乙凯[2] 

机构地区：[1]广州中医药大学附属佛山市中医院,广东佛山528000 [2]南方医科大学附属南方医院影像中心,广东广州510515

出　　处：《中国临床医学影像杂志》2010年第4期254-257,共4页Journal of China Clinic Medical Imaging

基　　金：佛山市科技局资助课题(项目编号:200808026)

摘　　要：目的:探讨超顺磁性氧化铁粒子(SPIO)增强MRI扫描在抗原诱导兔关节炎动物模型的滑膜巨噬细胞成像中的应用价值。方法:共8只致敏成年新西兰白兔通过右侧膝关节内注射卵清白蛋白的方法建立抗原诱导关节炎模型,左膝关节以相同的方式关节内注射等渗盐水溶液作为对照;关节炎模型建立之后经静脉注射SPIO对比剂,24h后行T1WI、T2WI、T2*WI序列MRI扫描;实验动物在SPIO增强后处死制成膝关节病理切片,并与MRI表现对照。结果:MRI平扫右膝关节见关节滑膜增生、关节积液增多,SPIO增强扫描T1WI序列2例出现右膝增生滑膜线条样阳性强化,T2WI序列6例右侧关节增生滑膜信号呈不均匀减低,关节积液有1例于T2WI出现信号减低,另6例信号改变不显著;T2*WI增强后7例右侧膝关节增生滑膜信号呈不均匀减低,关节积液有2例于T2*WI出现信号减低,另5例信号改变不显著。病理切片普鲁士蓝铁染色显示右膝增生的滑膜巨噬细胞胞浆内大量蓝色铁染色颗粒。结论:经静脉注射SPIO能够被抗原诱导兔关节炎模型的关节滑膜巨噬细胞吞噬,且在1.5T场强MRI条件下能够显示明确的增强效果。Objective： To investigate the application of superparamagnetic iron oxide （SPIO） in vivo to show macrophage specific MR imaging in the experimental rabbit model of antigen-induced arthritis. Methods： Arthritis was induced by means of intra-articular injection of ovalbumin in the right knee of 8 rabbits that had been presensitized to the same antigen. The left knees of the all eight rabbits were injected intra-articularly with 0.5ml of isotonic saline solution in a similar fusion as in the antigen-injected knees. After onset of arthritis, all knees were imaged before and 24 hours after administration of SPIO. The knees were scanned at 1.5T MRI by using T1-weighted spin-echo, T2-weighted spin-echo and T2^＊-weighted gradient-echo sequence. MRI findings were correlated with histopathologic findings. Results： Pre-contrast image showed joint effusion and synovium thickening. A significant enhancement was present in the synovium of 2 arthritic knees in post-contrast T1-weighted images. A distinct signal loss was noted in the synovium of the 6 arthritic knees in post-contrast T2-weighted images, while signal loss was noted in the synovium of all arthritic knees in post-contrast T2^＊-weighted images. Slight signal loss was present in 1 effusion of the arthritic knees with post-contrast T2-weighted images and in 2 effusions of the arthritic knees with post-contrast T2^＊-weighted images. Prussian blue stain identified iron particles within macrophages embedded in the cellular infiltrates of the arthritic knees. Conclusion： SPIO enhanced MR imaging at 1.5T is capable of detecting macrophage infiltration into the synovium in an experimental rabbit model of antigen-induced arthritis.

关 键 词：关节炎 类风湿 巨噬细胞 磁共振成像 

分 类 号：R593.21[医药卫生—内科学] R445.2[医药卫生—临床医学]