超顺磁性氧化铁对T2*加权梯度回波磁共振成像中肿瘤与肝脏对比度的影响：3.0T和1.5T磁共振系统的比较

Effect of superparamagnetic iron oxide on tumor-to-liver contrast at T2*-weighted gradient-echo MRI: comparison between 3.0T and 1.5T MR systems.

作者信息

Kim Tonsok, Murakami Takamichi, Hori Masatoshi, Onishi Hiromitsu, Tomoda Kaname, Nakamura Hironobu

机构信息

Department of Radiology, Osaka University Graduate School of Medicine, Osaka, Japan.

出版信息

J Magn Reson Imaging. 2009 Mar;29(3):595-600. doi: 10.1002/jmri.21384.

DOI:10.1002/jmri.21384

PMID:19243054

Abstract

PURPOSE

To compare 3.0T and 1.5T MR systems in terms of the effect of superparamagnetic iron oxide (SPIO) on tumor-to-liver contrast in T2*-weighted gradient-echo MRI.

MATERIALS AND METHODS

SPIO-enhanced gradient-echo MR images of the liver with four different TEs (3, 5.3, 6.5, and 8.5 msec) were obtained by means of 1.5T and 3.0T systems. Quantitative analyses of relative signal intensities (SIs) and relative tumor contrast and qualitative analyses of image quality and lesion conspicuity of the liver were performed in 22 patients, 16 of whom had malignant liver tumors.

RESULTS

With both 1.5T and 3.0T, at TE=8.4 msec, the relative SI of liver and relative tumor contrast were significantly (P<0.01) lower and higher, respectively, than that for any of the other TEs. There were no significant differences in the relative SI of the liver, relative tumor contrast, image quality, and tumor conspicuity for the same TE between the 1.5T and 3.0T systems.

CONCLUSION

Our results showed that the effect of SPIO on tumor-to-liver contrast at T2*-weighted gradient-echo imaging was similar for the 1.5T and 3.0T systems, and that the 8.4-msec TE was optimal of the four TEs used in this study at 3.0T.

摘要

目的

比较3.0T和1.5T磁共振（MR）系统在超顺磁性氧化铁（SPIO）对T2*加权梯度回波MRI中肿瘤与肝脏对比度影响方面的差异。

材料与方法

通过1.5T和3.0T系统获取了具有四种不同回波时间（TE，分别为3、5.3、6.5和8.5毫秒）的肝脏SPIO增强梯度回波MR图像。对22例患者进行了肝脏相对信号强度（SI）和相对肿瘤对比度的定量分析以及图像质量和病变清晰度的定性分析，其中16例患者患有肝脏恶性肿瘤。

结果

在1.5T和3.0T系统中，当TE = 8.4毫秒时，肝脏的相对SI显著低于（P<0.01）其他任何TE时的相对SI，而相对肿瘤对比度则显著高于（P<0.01）其他任何TE时的相对肿瘤对比度。对于相同的TE，1.5T和3.0T系统在肝脏相对SI、相对肿瘤对比度、图像质量和肿瘤清晰度方面均无显著差异。