NMR Based Diffusion Pore Imaging: A novel imaging concept

基于核磁共振的扩散孔隙成像：一种新颖的成像概念

基本信息

批准号：
232771676
负责人：
Professor Dr. Frederik B. Laun
金额：
--
依托单位：
Radiologisches Institut
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2013
资助国家：
德国
起止时间：
2012-12-31 至 2014-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/232771676?language=en
关键词：
NMR Based Diffusion Pore Imaging

项目摘要

Diffusion weighted imaging is a widely applied magnetic resonance technique in medical imaging, that is applied routinely in diagnostics of acute stroke. It is a technique that is often used to detect cellular structures hindering the diffusive motion, and in particular to detect the orientation of white matter tracts. For example, main white matter tracts can be reconstructed in an impressive manner. In the early 1990s, Paul Callaghan could show that nuclear magnetic resonance diffusion experiments can yield further information about the cellular structure. In particular, he could show that the magnitude spectrum of the pore space function can be measured using short diffusion gradients. The experiment can be interpreted as a scattering experiment. Unfortunately - as in x-ray crystallography - the phase information is lost, and an inverse Fourier transform cannot be performed. Thus the cell shape cannot be detected unambiguously.Recently, we could show theoretically how the shape of the pore can be measured unambiguously by modifying the temporal profile of the diffusion weighting magnetic field gradients. This is indeed a new imaging method, since the phased spectrum of the pore can be acquired, and since the inverse Fourier transform can be performed, similarly as in magnetic resonance tomography. The aim of this proposal is the experimental verification of the existing theoretical results. Therefore it is planned to- perform an in-depth analysis of the pore imaging technique in order to chose phantoms, sequence parameters etc. appropriately- perform pore imaging using hyperpolarized xenon as model for lung alveoli - perform pore imaging using water-filled capillaries as model for axonsBesides the pore imaging approach, the proposed modification of the diffusion weighting gradients yields a new magnetic resonance imaging contrast: The diffusion-weighted phase. Therefore, it is planned to analyze the properties of this new contrast, and perform magnetic resonance imaging based on it.

扩散加权成像是医学成像中广泛应用的磁共振技术，通常用于急性中风的诊断。这是一种通常用于检测妨碍扩散运动的细胞结构，尤其是用于检测白质区的方向。例如，主要的白质区域可以以令人印象深刻的方式重建。在1990年代初期，保罗·卡拉汉（Paul Callaghan）可以证明核磁共振扩散实验可以产生有关细胞结构的进一步信息。特别是，他可以证明可以使用短扩散梯度来测量孔隙空间函数的幅度光谱。该实验可以解释为散射实验。不幸的是 - 与X射线晶体学中一样 - 相位信息丢失，并且无法执行逆傅立叶变换。因此，无法明确地检测到细胞形状。从理论上讲，我们可以通过修改扩散权重磁场梯度的时间分布来表明如何明确测量孔的形状。这确实是一种新的成像方法，因为可以获取孔的分阶段光谱，并且由于可以进行逆傅立叶变换，就像在磁共振断层扫描中一样。该提案的目的是对现有理论结果的实验验证。 Therefore it is planned to- perform an in-depth analysis of the pore imaging technique in order to chose phantoms, sequence parameters etc. appropriately- perform pore imaging using hyperpolarized xenon as model for lung alveoli - perform pore imaging using water-filled capillaries as model for axonsBesides the pore imaging approach, the proposed modification of the diffusion weighting gradients yields a new magnetic resonance imaging对比：扩散加权阶段。因此，计划分析这种新对比度的性质，并基于它进行磁共振成像。