The Design Of A Multi-channel Transceiver RF Coil For Mri And Its Application In MR EPT Technology

A large number of scientific studies have proved that the electrical properties of human tissues?such as the conductivity and permitivity?reflect the physiological and pathological information of the tissues,that the electrical properties of healthy tissues and tumor tissues are very different.Therefore,it will bring great clinical application value to early detection of cancers if we can measure the electrical properties of tissues by some technical methods.Magnetic resonance electrical properties tomography?MR EPT?of human tissues is based on the advantages of non-invasive non-radiation,high resolution and strong signal-to-noise ratio?SNR?of magnetic resonance imaging?MRI?,and relies on the fact that the distribution of the image include the distribution of the electrical properties of tissues.The tomography of electrical properties of tissues can be obtained by utilizing some reconstruction algorithms after the measurement of the transmitted RF field.This technique has developed rapidly in the last ten years,but how to improve the reconstruction accuracy of electrical properties is still the research problem of this technology.The progress of MR EPT technology upon not only in the improvement of reconstruction algorithm,the development of RF coil will also promote the development of MR EPT technology.A multi-channel phased array transceiver coil designed in this paper can not only speed up the magnetic resonance scanning speed and improve the imaging signal to noise ratio,but also can flexibly change the transmission field to obtain the multiple degrees of freedom date from the B₁ field.The new EPT reconstruction algorithm can be used to improve the reconstruction accuracy of the electrical properties of tissues by obtaining the data from B₁ field.Based on the principle of MR EPT technology,this paper will carry out the following work on the basis of Alltech's EchoStar 1.5T MR system:Part ?:We introduce the principle and development status of magnetic resonance imaging technology,phased array RF coils and MR EPT technology.Part ?:We designed and optimized the eight channel phased array receiving/transmitting integrated head coils for MR EPT technology,as well as the RF circuit module for parallel launch technology.Part ?:Verify the performance of multi-channel transceivers and compare the imaging results with the birdcage coil.Part ?:We will conduct parallel emission experiments to improve the disadvantages of conventional transmitter coil?birdcage coil?:Single excitation mode,inflexible adjustment of emission parameters such as amplitude and phase.And calculate the amplitude and phase of the transmit field,to do some basic exploration work for the follow-up project progress.