Xia Qian, Feng Yuanbo, Yin Ting, Liu Yewei, Liang Sayuan, Liu Jianjun, Tong Linjun, Huang Gang, Yu Jie, Jiang Yansheng, Himmelreich Uwe, Oyen Raymond, Ni Yicheng
Department of Nuclear Medicine, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
Department of Imaging and Pathology, University Hospitals, KU Leuven, Leuven 3000, Belgium.
Microsc Res Tech. 2016 Feb;79(2):111-21. doi: 10.1002/jemt.22612. Epub 2016 Jan 8.
We sought to devise and test a multifunctional contrast dye agent for X-ray based digital radiography (DR) or computer tomography (CT), magnetic resonance imaging (MRI), and colored staining in ex vivo validation part of animal experiments.
The custom-formulated contrast dye namely red iodized oil (RIO) was prepared by solubilizing a lipophilic dye Oil Red O in iodized poppy seed oil (Lipiodol or LPD) followed by physicochemical characterizations. To explore and test the utility of RIO, normal rats (n = 10) and rabbits (n = 10) with myocardial infarction (MI) were euthanized by overdose of pentobarbital for infusion of RIO through catheterization. The bodies and/or excised organs including heart, liver, spleen, kidneys, pancreas, and intestines of the rats and rabbits were imaged at clinical mammography, CT and MRI units. These images were qualitatively studied and quantitatively analyzed using Wilcoxon Rank test with a P value < 0.05 being considered of a statistically significant difference. Imaging findings were verified by histomorphology.
All experimental procedures were carried out successfully with the use of RIO. T1 and T2 relaxation time was 234.2 ± 2.6 ms and 141.9 ± 3.0 ms for RIO, close to that of native LPD. Proton ((1) H) NMR spectroscopy revealed almost identical profiles between RIO and native LPD. The clinical mammography unit, 128-slice CT scanner and 3.0T MRI magnet were well adapted for the animal experiments. Combined use of RIO with DR, MRI, CT and histology enabled microangiography of the organs, 3D visualization of rat pancreas, validation of in vivo cardiac quantification of MI and cause determination of the rabbit death after coronary occlusion. RIO appeared as red droplets and vacuoles in vessels by frozen and paraffin sections. Image analysis showed the superiority of DR images, which provided better overall image quality (4.35 ± 0.49) for all analyzed liver vessel segments. MRI images revealed moderate to good overall image quality ratings (3.45 ± 0.52). Comparing the signal intensities of vessel and liver with different MRI sequences, all P values were <0.01.
RIO proved to be a multifunctional contrast dye, which could be applied as an imaging biomarker for tissue vascularity or blood perfusion, for visualization of organ anatomy and for ex vivo validation of in vivo animal experiments.
我们试图设计并测试一种多功能造影剂，用于基于X射线的数字X线摄影（DR）或计算机断层扫描（CT）、磁共振成像（MRI）以及动物实验离体验证部分的彩色染色。
定制配方的造影剂即红色碘化油（RIO），是通过将亲脂性染料油红O溶解于碘化罂粟籽油（Lipiodol或LPD）中制备而成，随后进行了物理化学表征。为探究和测试RIO的效用，对10只正常大鼠和10只患有心肌梗死（MI）的兔子过量注射戊巴比妥使其安乐死，通过导管注入RIO。对大鼠和兔子的尸体及/或切除的器官，包括心脏、肝脏、脾脏、肾脏、胰腺和肠道，在临床乳腺摄影、CT和MRI设备上进行成像。使用Wilcoxon秩和检验对这些图像进行定性研究和定量分析，P值<0.05被认为具有统计学显著差异。成像结果通过组织形态学进行验证。
使用RIO成功完成了所有实验步骤。RIO的T1和T2弛豫时间分别为234.2±2.6毫秒和141.9±3.0毫秒，与天然LPD接近。质子（¹H）核磁共振波谱显示RIO与天然LPD的谱图几乎相同。临床乳腺摄影设备、128层CT扫描仪和3.0T MRI磁体非常适合动物实验。RIO与DR、MRI、CT及组织学联合使用，能够实现器官的微血管造影、大鼠胰腺的三维可视化、体内心肌梗死定量的验证以及冠状动脉闭塞后兔子死亡原因的确定。在冷冻切片和石蜡切片中，RIO在血管中表现为红色液滴和空泡。图像分析显示DR图像具有优势，对于所有分析的肝血管段，其提供了更好的整体图像质量（4.35±0.49）。MRI图像显示整体图像质量评级为中等至良好（3.45±0.52）。比较不同MRI序列下血管和肝脏的信号强度，所有P值均<0.01。
RIO被证明是一种多功能造影剂，可作为组织血管或血流灌注的成像生物标志物，用于器官解剖结构的可视化以及体内动物实验的离体验证。
