解决MRI通道互扰的有线调频传输方法研究

发布时间：2018-02-27 12:15

本文关键词： 磁共振成像相控阵线圈信号传输互扰　出处：《华东师范大学》2012年硕士论文　论文类型：学位论文

【摘要】：核磁共振成像技术(Magnetic Resonance Imaging, MRI)自1973年诞生以来,由于它具有无损伤性检测、图像对比度高等特点,被广泛应用于生物、医学、勘探等多个领域中,而近年来相控阵和并行成像技术的快速发展更是进一步提升了MRI在上述领域中的实用性。对于MRI系统的布局,由于受到MRI系统周围强磁场环境的限制,接收机必须远离MRI系统的磁体部分。在较早的并行成像技术中,接收机与相控阵线圈之间信号的传输采用多条电缆来实现。但在实际应用中,电缆之间信号的互扰以及电磁环境对电缆的耦合等因素会导致图像质量下降。针对这一问题已有多种解决方法被提出,主要可分为光纤传输方案和无线传输方案。这些方法虽然解决了各通道间的互扰问题,但仍有其自身的缺点。其一,相对于磁共振信号,光纤和无线技术的动态范围过小,这将会造成信号波形的扭曲;其二,实现时操作技术复杂且成本较高。本文主要工作是研制一种有线调频传输方法,此方法能有效地抑制了信号传输时各通道间信号的互扰,同时最大限度地减少了电磁环境与电缆的耦合。本论文主要内容如下：第一部分：简要介绍核磁共振成像发展及现状、相控阵线圈及并行成像技术。第二部分：简要介绍目前解决MRI成像时各通道间信号互扰问题的方法以及其各自存在的问题。第三部分：主要介绍本文提出的用于解决互扰问题的有线调频传输方法及其实现,并给出电路测试结果第四部分：主要介绍为验证有线调频传输方法而研制的三通道相控阵线圈,并给出线圈的测试结果。第五部分：给出成像实验结果及其分析。
[Abstract]:Magnetic Resonance Imaging (MRI) has been widely used in many fields, such as biology, medicine, exploration and so on, since it was born in 1973. In recent years, the rapid development of phased array and parallel imaging technology has further improved the practicability of MRI in these fields. For the layout of MRI system, due to the restriction of the strong magnetic field surrounding the MRI system, the receiver must be far from the magnet part of the MRI system. The signal transmission between the receiver and the phased array coil is realized by multiple cables. However, in practical application, The interference of signals between cables and the coupling of the electromagnetic environment to the cable will lead to the deterioration of image quality. Many methods have been proposed to solve this problem. These methods can be divided into optical fiber transmission schemes and wireless transmission schemes. Although these methods solve the problem of mutual interference between channels, they still have their own disadvantages. First, compared with magnetic resonance signals, the dynamic range of optical fiber and wireless technology is too small. This will cause distortion of the signal waveform. Second, the operation technology is complex and the cost is high. The main work of this paper is to develop a wired FM transmission method, which can effectively suppress the signal interference between the channels and minimize the coupling between the electromagnetic environment and the cable. The main contents of this thesis are as follows:. The first part: the development and present situation of nuclear magnetic resonance imaging, phased array coil and parallel imaging technology. In the second part, the methods to solve the problem of signal interferences between channels in MRI imaging and their respective problems are briefly introduced. The third part: this paper mainly introduces the cable frequency modulation transmission method and its implementation to solve the problem of mutual disturbance, and gives the circuit test results. Part 4th: the three-channel phased array coil developed to verify the wired FM transmission method is introduced, and the test results of the coil are given. Part 5th: the experimental results and their analysis are given.
【学位授予单位】：华东师范大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.6

【参考文献】