Wide Field MR Microscopy using Integrated Gradient and RF Array Coils

描述(申请人提供)：这项EBRG提案的目标是开发和展示一种新的高分辨率磁共振成像技术，广域磁共振显微镜(MRM)。磁共振显微镜被大多数人定义为在任何维度上的分辨率为100微米或更低的成像，由于其能够以高分辨率非侵入性地探测体内和体外组织，同时提供MRI的许多对比机制，随着医学的未来明显地走向细胞水平，MR显微镜将成为一种无价的工具。在提供组织微环境的高分辨率成像的同时，传统的MRM通过使用旨在提高信噪比的小射频线圈来限制在非常小的视场内，或者可替换地，通过以高分辨率在大视场上编码MR图像所需的时间来限制常规MRM。这项工作提出了一种宽视场MR显微镜的方法。这项技术结合了并行成像和独特的相位校正梯度通道，可以在大大减少成像时间的情况下，在大视场上实现高分辨率MRI。该项目将开发的技术进步是集成的梯度和RF阵列线圈，它为用户提供了极高分辨率成像或极快成像(分辨率降低)之间的选择。两者都是通过使用或更多对准的接收器线圈阵列来并行成像过程来实现的，从而减少了对基于梯度的相位编码的依赖。高速数字接收器可以使视场沿平行线圈的长轴增大，而并行成像则在相反方向增大视场。将优化平面梯度线圈，并将独立的第四梯度通道集成到MR扫描仪中，以补偿接收线圈带来的距离相关相移，这些相移降低了高速MR成像中的信号强度。最后，一个对广域磁共振显微镜的潜力感兴趣的合作者团队，包括两名磁共振显微镜专家和三名临床科学家，将提供不同类型的组织样本，用于测试和评估新方法。如果成功，该项目将使磁共振显微镜拥有比以前更广阔的视角和更快的速度，将其扩展到更广泛的应用领域。磁共振显微镜将临床磁共振成像的能力扩展到极高的分辨率，潜在地向下延伸到细胞分辨率。该项目的目标是开发一种新的技术，广场磁共振显微镜，它将并行成像与独特的相位校正梯度相结合，以大大减少成像时间，实现大视场的高分辨率磁共振成像。这项技术是由一种新的探头设计实现的，它将提供在同一视野内以极高的空间分辨率或极高的时间分辨率进行磁共振显微镜检查的能力。

DESCRIPTION (provided by applicant): The objective of this EBRG proposal is to develop and demonstrate a new high resolution MR imaging technique, wide-field magnetic resonance microscopy (MRM). MR microscopy, defined by most as imaging with a resolution of 100 microns or less in any dimension, will become an invaluable tool as the future of medicine clearly moves towards the cellular level due to its ability to non-invasively probe in vivo and in vitro tissue with high-resolution while providing the many contrast mechanisms of MRI. While providing high resolution imaging of the tissue microenvironment, conventional MRM is limited to a very small field-of-view by the use of small radiofrequency coils designed to improve the signal-to-noise ratio, or, alternatively, by the time required to encode the MR image over a large field-of-view at high-resolutions. This work proposes a method for wide field MR microscopy. This technique combines parallel imaging and a unique phase correcting gradient channel to enable high resolution MRI over a large field-of-view at greatly reduced imaging times. The technological advancement to be developed in this project is an integrated gradient and RF array coil which provides the user a choice between extremely high-resolution imaging or extremely fast imaging (at reduced resolution). Both are enabled by using an array of 64 or more aligned receiver coils to parallelize the imaging process, reducing reliance on gradient-based phase encoding. High- speed digital receivers enable the field-of-view to be increased along the long-axis of the parallel coils, while parallel imaging increases the field-of-view in the opposite direction. A planar gradient coil will be optimized and an independent, fourth gradient channel integrated into the MR scanner to compensate for distant dependent phase shifts imparted by the receive coils which reduce signal strength in highly accelerated MR imaging. Finally, a team of collaborators interested in the potential of wide-field MR microscopy, including two experts in MR microscopy and three clinical scientists, will provide tissue samples of different types for testing and assessing the new method. If successful, this project will enable MR microscopy with wider perspective and higher speed than previously possible, extending it into a broader range of applications. Magnetic resonance microscopy extends the power of clinical magnetic resonance imaging to extremely high resolutions, potentially down to cellular resolution. The goal of this project is to develop a new technique, wide field MR microscopy, which combines parallel imaging with a unique phase correcting gradient to enable high resolution MRI over a large field of view at greatly reduced imaging times. This technique is enabled by a new probe design which will provide the ability to perform MR microscopy at either extremely high spatial resolution or extremely high temporal resolution over the same field-of-view.