Brushett Chris, Qiu Bensheng, Atalar Ergin, Yang Xiaoming
Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
J Magn Reson Imaging. 2008 Jan;27(1):246-50. doi: 10.1002/jmri.21174.
To evaluate the potential of using motexafin gadolinium (MGd) to characterize atherosclerotic plaques of deep-seated arteries with MRI.
We exposed vascular endothelial cells (EC) and smooth muscle cells (SMC) in vitro to varying concentrations of MGd. The fluorescence properties of MGd were then exploited using confocal microscopy to image exposed cells. For an in vivo validation study, we performed surface coil-based and intravascular coil-based high-resolution MRI of the iliac arteries and the abdominal aorta of three atherosclerotic Yucatan pigs. Subsequently, MGd enhancement of the target vessel walls was quantitatively evaluated and MR images were correlated with histology of the target vessels.
The in vitro study confirmed the intracellularization of MGd in both cell types and determined the optimum MGd dosage of 0.004 mmol/kg that produced the sufficiently high intracellular fluorescent intensity. The in vivo study showed a steady increase of MGd enhancement to approximately 25% at three hours postinjection of MGd. MRI showed areas of strong enhancement along the lumen boundary, which corresponded to fibrous tissue seen in histology.
This study provides initial evidence that MGd may enhance MR vessel wall imaging for the characterization of plaque in deep-seated arteries.
评估使用莫特沙芬钆（MGd）通过磁共振成像（MRI）对深部动脉粥样硬化斑块进行特征性分析的潜力。
我们在体外将血管内皮细胞（EC）和平滑肌细胞（SMC）暴露于不同浓度的MGd。然后利用共聚焦显微镜观察MGd的荧光特性，对暴露的细胞进行成像。在一项体内验证研究中，我们对三头患有动脉粥样硬化的尤卡坦猪的髂动脉和腹主动脉进行了基于表面线圈和基于血管内线圈的高分辨率MRI检查。随后，对目标血管壁的MGd增强情况进行了定量评估，并将MR图像与目标血管的组织学结果进行了对比。
体外研究证实了两种细胞类型中MGd均发生内化，并确定了产生足够高细胞内荧光强度的最佳MGd剂量为0.004 mmol/kg。体内研究显示，注射MGd后3小时，MGd增强呈稳步上升，至约25%。MRI显示沿管腔边界有明显增强区域，这与组织学中所见的纤维组织相对应。
本研究提供了初步证据，表明MGd可能增强MR血管壁成像，用于深部动脉斑块的特征性分析。
