Radio Frequency Coil Design for Ultra High Field MRI

射频（RF）线圈是磁共振成像（MRI）系统的重要组件。由于在高磁场（>= 3 T）下人体内的RF场/组织相互作用，头部大小的体积线圈的发射曲线显示出独特的模式，其中大脑中心具有相对较强的RF磁场B（1+）。该中心增亮效应可以影响图像或频谱的定量和定性方面。由于组织-B（1+）场相互作用带来的不均匀性，在整个感兴趣体积中发现了更令人不安的建设性和破坏性B（1+）模式。我们研究计划的目的是设计RF线圈组件，使人体受试者在7 T下的发射（B1+）和接收（B1-）场RF不均匀性最小化。

Radio Frequency (RF) coils are an essential component of magnetic resonance imaging (MRI) systems. Due to RF field/tissue interactions in the human body at high magnetic fields (>= 3 T) the transmit profile from head-sized volume coils shows a distinctive pattern with a relatively strong RF magnetic field B(1+) in the center of the brain, This centre brightening effect can affect both quantitative and qualitative aspects of the image or spectrum. Even more troubling, constructive and destructive B(1+) patterns are found throughout the volume of interest due to the in homogeneities brought about by tissue-B(1+) field interaction The objective of our research program is to design RF coil assemblies that minimize the transmit (B1+) and receive (B1-) field RF in homogeneities at 7 T in human subjects.