High-resolution three-dimensional MR angiography of rodent tumors: Morphologic characterization of intratumoral vasculature
High-resolution three-dimensional MR angiography of rodent tumors: Morphologic characterization of intratumoral vasculature
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DOI：
10.1002/jmri.10318
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发表时间：
2003-07-01
影响因子：
4.4
通讯作者：
Delorme, S
中科院分区：
文献类型：
--
作者：
Fink, C;Kiessling, F;Delorme, S
目的：评价高分辨率三维磁共振血管成像（MRA）对肿瘤内血管的可视化和形态学表征。材料与方法：采用临床1.5 T磁共振成像系统检测两种啮齿动物皮下肿瘤模型（裸鼠生长的人皮肤癌HaCaT-ras-A-5RT3和哥本哈根大鼠生长的大鼠前列腺癌R3327-AT1）。在注射Gadomer-17后，MRA采用专用的高分辨率三维梯度回波脉冲序列，体素大小为166 x 206 x 320 mum(3)。图像分析包括肿瘤内血管与组织学的相关性。信号强度测量在腔静脉、肿瘤下肌和肿瘤的各个区域进行。由此计算信噪比（SNR）和噪声对比比（CNR）。结果：高分辨率MRA能够清晰区分肿瘤内血管。小鼠肿瘤模型呈强血管化趋势，MRA显示肿瘤内多条血管清晰可见。当与组织学相关联时，这些肿瘤内血管的大小在300至400 μ m之间。相比之下，大鼠肿瘤只有稀疏的毛细血管，只能通过组织学来证明。两种肿瘤模型均可见肿瘤附近皮下组织血管扩张。一般来说，对比增强强的区域与存活的、血管化良好的肿瘤区域相关，而未增强的肿瘤区域与肿瘤坏死或缺氧区域相关。结论：高分辨率的三维MRA可以可视化啮齿动物模型的肿瘤内血管系统。通过最小的硬件和软件修改，高分辨率MRA可以在临床1.5 T MRI扫描仪上进行。瘤内血管的形态学特征可以为肿瘤血管生成过程提供重要的见解。
Purpose: To evaluate high-resolution three-dimensional MR angiography (MRA) for the visualization and morphologic characterization of intratumoral vasculature.Materials and Methods: Two subcutaneous rodent tumor models (human skin carcinoma HaCaT-ras-A-5RT3 grown in nude mice and rat prostate carcinoma R3327-AT1 grown in Copenhagen rats) were examined with a clinical 1.5 T MR-system. For MRA a dedicated high-resolution three-dimensional gradient echo pulse sequence with a voxel size of 166 x 206 x 320 mum(3) was performed after injection of Gadomer-17. The image analysis included a correlation of intratumoral vessels with histology. Signal intensity measurements were performed in the vena cava, the tumor underlying muscle, and in various regions of the tumor. Signal-to-noise-ratios (SNR) and contrast-to-noise-ratios (CNR) were calculated from this measurement.Results: High-resolution MRA allowed a clear distinction of intratumoral blood vessels. The mouse tumor model tended to be strongly vascularized with several intratumoral blood vessels clearly displayed by MRA. When correlated with histology, these intratumoral blood vessels had a size in the range of 300 to 400 mum. In contrast, rat tumors had only sparse capillary intratumoral blood vessels that could only be demonstrated by histology. In both tumor models, dilated blood vessels were observed in the subcutaneous tissue near the tumor. In general, areas with a strong contrast enhancement correlated with viable, well vascularized tumor regions, whereas non-enhancing tumor areas correlated with tumor necrosis or hypoxic areas.Conclusion: High-resolution three-dimensional MRA allows the visualization of intratumoral vasculature in rodent models. With minimal hardware and software modifications, high-resolution MRA could be performed on a clinical 1.5 T MRI scanner. Morphologic characterization of intratumoral blood vessels could add important insights into the process of tumor angiogenesis.