Watrin-Pinzano Astrid, Loeuille Damien, Goebel Jean-Christophe, Lapicque Françoise, Walter Fredéric, Robert Philippe, Netter Patrick, Corot Claire, Gillet Pierre, Blum Alain
Faculté de Médecine de Nancy, UMR 7561 CNRS - Nancy Université, France.
Biomed Mater Eng. 2008;18(4-5):261-72.
The purpose of this study was to assess 2 Gd-based macromolecular intravascular contrast agents (P792, rapid clearance blood pool agent (rBPA) and P717, slow clearance blood pool agent (sBPA)) compared to Gd-DOTA (representative extracellular non specific agent) in MR imaging of knee rabbit experimental synovitis. Quantitative dynamic contrast enhanced MRI (qDCE-MRI) after intravascular injection of a low molecular weight contrast agent of 0.56 kDa (Gd-DOTA) and 2 high-molecular-weight contrast agents of 6.47 kDa (P792) and 52 kDa (P717) was performed in rabbits with carrageenan-induced synovitis of the right knee. P792 and P717 provided a progressive and persistent enhancement of arthritic synovial tissue while Gd-DOTA provided an early and rapidly declining enhancement with a concomitant diffusion in synovial fluid, thus limitating delineation of synovial pannus. P792 allowed acquisition of high-quality MR arthrograms, due to both a better diffusion in synovial pannus (vs. P717) and a concomitant restricted diffusion into the synovial fluid (vs. Gd-DOTA). In fact, experimental rabbit synovitis represent a specific entity that favors the T1 effect of high-molecular-weight agents, and especially rBPA P792, entrapped in synovial pannus, without diffusion in the synovial fluid. Due to this lack of arthrographic effect, P792 accumulation could be specifically sequentially analyzed by qDCE-MRI for detecting, characterizing and monitoring synovial vascular permeability changes during mono- or polysynovitis.
本研究的目的是在兔膝关节实验性滑膜炎的磁共振成像中，将两种基于钆的大分子血管内造影剂（P792，快速清除血池剂（rBPA）和P717，缓慢清除血池剂（sBPA））与钆喷酸葡胺（代表性的细胞外非特异性造影剂）进行评估比较。对右膝关节注射角叉菜胶诱导滑膜炎的兔子，血管内注射0.56 kDa的低分子量造影剂（钆喷酸葡胺）以及6.47 kDa（P792）和52 kDa（P717）的两种高分子量造影剂后，进行定量动态对比增强磁共振成像（qDCE-MRI）。P792和P717使关节炎性滑膜组织呈渐进性持续强化，而钆喷酸葡胺则早期快速强化下降，同时在滑液中扩散，从而限制了滑膜血管翳的勾勒。P792能获得高质量的磁共振关节造影图，这是因为其在滑膜血管翳中的扩散更好（与P717相比），同时向滑液中的扩散受限（与钆喷酸葡胺相比）。事实上，实验性兔滑膜炎代表了一种特殊情况，有利于高分子量造影剂，尤其是被困在滑膜血管翳中而不在滑液中扩散的rBPA P792的T1效应。由于缺乏关节造影效果，通过qDCE-MRI可对P792的蓄积进行特异性的序列分析，以检测、表征和监测单关节或多关节滑膜炎期间滑膜血管通透性的变化。
