Abstract

We consider the effect of various radio frequency (rf) pulse sequences on the contrast of magnetic resonance (MR) images. We have developed a program for simulating magnetic resonance tomograms and for determining optimal values of parameters of rf pulse sequences for obtaining the best contrast of MR images. This program has been tested for MRI experiments with negative contrast agents based on magnetic iron oxide nanoparticles and positive contrast agents based on gadolinium. Their effect on the MR signal intensity depending on concentration has been analyzed. Recommendations concerning the choice of optimal values of parameters of rf sequences for MRI diagnostics using contrast agents have been developed.

中文翻译：

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磁性纳米粒子存在下用于MRI研究的RF脉冲序列参数的优化

摘要

我们考虑了各种射频（rf）脉冲序列对磁共振（MR）图像对比度的影响。我们已经开发了一个程序，用于模拟磁共振断层图和确定射频脉冲序列参数的最佳值，以获得MR图像的最佳对比度。该程序已通过基于磁性氧化铁纳米粒子的负性造影剂和基于g的正性造影剂的MRI实验进行了测试。已经分析了它们根据浓度对MR信号强度的影响。已经提出了关于使用造影剂进行MRI诊断的rf序列参数的最佳值的选择的建议。