Zheng Jie, Ochoa Elizabeth, Misselwitz Bernd, Yang Deshan, El Naqa Issam, Woodard Pamela K, Abendschein Dana
Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri 63110, USA.
Invest Radiol. 2008 Jan;43(1):49-55. doi: 10.1097/RLI.0b013e318155aa5a.
Gadofluorine M has been reported to enhance early atherosclerotic plaque signals in magnetic resonance imaging (MRI). The aim of this study was to examine the use of Gadofluorine M to monitor the progression of advanced plaques in a rabbit model.
Focal advanced atherosclerosis was induced in the right femoral arteries of 6 New Zealand white rabbits using a combination of cholesterol-enriched diet, and sequential air-desiccation, and balloon-overstretch injury. MRI with conventional 3 contrasts (T1, T2, and proton density [PD]) was performed to monitor the progression of the atherosclerotic plaques with 2 MRI scans separated by 4 to 8 weeks. Gadofluorine M was given intravenously to the rabbits 24 hours before the first MRI scans, and before (n = 3) or during (n = 3) the second MRI scan. The left femoral arteries were used as a control. Histopathologic images localized individual plaque components.
The advanced plaque displayed multilayered neointima that included foam cells, smooth muscle cells, and extracellular matrix. The separate image contrasts offered similar T1-weighted enhancement patterns, but the combination of all 3 contrasts helped to delineate plaque and lumen boundaries. Gadofluorine M strongly enhanced neointima areas with an image contrast (contrast-to-noise ratio [CNR]) of approximately 15, versus 2 in the control femoral arterial wall. With improved images, significant changes in neointima and total plaque volumes over the 4 to 8 weeks between scans could be identified. Gadofluorine M remained within the plaques with significant image enhancements (contrast-to-noise ratio = 5.8) for 2 months after a single injection.
This preliminary study in rabbits indicated that Gadofluorine M provides specific enhancements of components associated with advanced atherosclerotic plaques and may help to monitor the progression of the plaque in a rabbit model of atherogenesis.
据报道，钆双胺在磁共振成像（MRI）中可增强早期动脉粥样硬化斑块信号。本研究旨在探讨钆双胺在兔模型中监测晚期斑块进展情况的应用。
对6只新西兰白兔的右股动脉采用高胆固醇饮食、序贯空气干燥和球囊过度扩张损伤相结合的方法诱导局灶性晚期动脉粥样硬化。使用传统的3种对比剂（T1、T2和质子密度[PD]）进行MRI检查，以监测动脉粥样硬化斑块的进展情况，两次MRI扫描间隔4至8周。在第一次MRI扫描前24小时，以及在第二次MRI扫描前（n = 3）或扫描期间（n = 3）给兔子静脉注射钆双胺。左股动脉用作对照。组织病理学图像定位了各个斑块成分。
晚期斑块显示出多层新生内膜，其中包括泡沫细胞、平滑肌细胞和细胞外基质。单独的图像对比提供了相似的T1加权增强模式，但所有3种对比剂的组合有助于勾勒斑块和管腔边界。钆双胺强烈增强了新生内膜区域，图像对比（对比噪声比[CNR]）约为15，而对照股动脉壁为2。随着图像质量的提高，可以识别出两次扫描之间4至8周内新生内膜和总斑块体积的显著变化。单次注射后，钆双胺在斑块内保持显著的图像增强（对比噪声比 = 5.8）达2个月。
这项在兔子身上的初步研究表明，钆双胺能特异性增强与晚期动脉粥样硬化斑块相关的成分，并可能有助于在动脉粥样硬化发生的兔模型中监测斑块的进展。
