NOVEL ENCODING TECHNOLOGY FOR ULTRAFAST MRI

本文提出的研究目标是：1）设计和建造一个 一种新型的磁场编码线圈系统， 共振成像仪和2）实现和测试这两个应用程序 线圈系统这两个应用是：1）超快成像方法， 2)非常有效的定量血流成像技术， 这是通过编码线圈的关节几何形状实现的。 使用完全不同的场几何学，新的数学算法 对于静态和流动自旋的成像提出了建议。研究 本文提出的是完成线圈系统的设计，然后 建立一个原型。将对快速成像应用程序进行测试， 使用计算机模拟进行改进，然后进行实验测试。的 流动成像方法将进一步发展和实验测试 在已知速度分布的情况下， 先验的 拟议中的超快静态成像技术提供了机会， 用于成像而不必切换编码线圈中的电流。 因此，这种技术理论上比目前可用的技术更快。 (i.e.回波平面）。此外，由于主动屏蔽梯度 这种方法不需要线圈，实现这种方法的成本 方法可能基本上小于回波平面。的 低成本实时成像的可用性可能会大大影响 医学界快速成像的可用性。 所提出的流动成像方法提供了获得 核的单次激发中的定量速度信息， 因此也使得该方法非常省时。的可用性 一种快速、准确和定量的速度测量MRI方法， 为这种非侵入性技术带来了新的诊断能力。

The aims of the research proposed herein are 1) to design and build a new type of magnetic field encoding coil system to be used in a Magnetic Resonance Imager and 2) to implement and test two applications of this coil system. The two applications are 1) an ultrafast imaging method and 2) extremely efficient quantitative flow imaging techniques, both of which are enabled by the articular geometry of the encoding coils. Using a radically different field geometry, new mathematical algorithms for imaging static and flowing spins are suggested. The research proposed herein is to complete the design of the coil system and then build a prototype. The rapid imaging application will be tested and refined using computer simulations and then tested experimentally. The flow imaging methods will be further developed and tested experimentally with a variety of flow phantoms where the velocity distribution is known a priori. The proposed ultrafast static imaging technique offers the opportunity for imaging without having to switch the current in the encoding coil. Hence, this technique is theoretically faster than those available today (i.e. echo-planar). In addition, because actively shielded gradient coils are not required for this method, the costs of implementing such a method are likely to be substantially less than for echo planar. The availability of low cost real-time imaging could substantially influence the availability of rapid imaging to the medical community. The proposed flow imaging methods offer the opportunity to obtain quantitative velocity information in a single excitation of the nuclei, thus also making this method extremely time efficient. The availability of a fast, accurate and quantitative velocity measuring MRI method would bring new diagnostic capabilities to this noninvasive technique.