13C, SPIRAL CHEMICAL SHIFT IMAGING, SPECTRAL UNDERSAMPLING, PYRUVATE, LACTATE

13C，螺旋化学位移成像，光谱欠采样，丙酮酸盐，乳酸盐

• 批准号: 7601881
• 负责人: DIRK MAYER
• 金额: $ 1.15万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-06-01 至 2008-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7601881
• 关键词: Alanine; Alcoholism; Blur; Brain imaging; Chemical Shift Imaging; Complement component C1s; Computer Retrieval of Information on Scientific Projects Database; Data; Data Set; Development; Diffusion; Equilibrium; Esters; Frequencies; Funding; Funding Agency; Grant; Image; Institution; Knowledge; Magnetic Resonance; Magnetic Resonance Imaging; Maps; Measurement; Metabolic; Methods; Minor; Morphologic artifacts; Phase; Positioning Attribute; Property; Publications; Pyruvate; Pyruvates; Research; Research Personnel; Resolution; Resources; Scheme; Signal Transduction; Solutions; Source; Speed; System; Technology; Testing; Time; United States National Institutes of Health; in vivo; neoplasm imaging; reconstruction

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Introduction: The development of hyperpolarized, metabolically active MRI agents presents both unprecedented opportunities as well as new technical challenges. While it theoretically permits in vivo imaging of not only the substrate, but also downstream metabolic products, the decay of the longitudinal magnetization demands fast acquisition schemes. The need for speed in combination with the sparse spectra which can occur in the application of hyperpolarized 13C metabolic imaging makes spiral chemical shift imaging (spCSI) an ideal candidate for this application. Methods and Discussion: The implemented sequence exploits sparse spectra and prior knowledge of resonance frequencies to reduce the measurement time by undersampling the data in the spectral domain. As a consequence, multiple reconstructions of a given data set have to be computed in which only components with frequencies within a certain bandwidth are reconstructed in-focus while other are severely blurred (spectral tomosynthesis). The sequence was tested at 3 T on a phantom containing solutions of alanine (Ala), lactate (Lac), and pyruvate-pyruvate hydrate C1-C2 ester (with two resonances, PPE1 and PPE2) at thermal equilibrium polarization, all enriched to 99% 13C in the C1 carbonyl positions. Spiral CSI with a single spatial interleaf (single-shot spCSI) and 3 interleaves (3-shot spCSI), respectively, were compared to phase-encoded CSI (FIDCSI). Metabolic maps of all four resonances for 3-shot spCSI and of PPE1 and PPE2 for single-shot spCSI demonstrate similar resolution and localization properties as the FIDCSI images. Metabolic maps of Ala and Lac for single-shot spCSI contain minor artifacts due to signal overlap of aliased resonances. Funding Sources " P41 RR009784, Center for advanced MR Technology at Stanford, Gary H. Glover, 01/01/1995-5/31/2010 " R01 CA048269, Magnetic Resonance Spectroscopic Neoplasm Imaging, Daniel M. Spielman, 7/23/1990-7/31/2006 " R01 AA012388, In Vivo Diffusion and Spectroscopic Brain Imaging in Alcoholism, Adolf Pefferbaum, 8/1/2000-6/30/2010 Relevant publications " D. Mayer, Y.S. Levin, R.E. Hurd, G.H. Glover, D.M. Spielman Fast Metabolic Imaging of Systems with Sparse Spectra: Application for Hyperpolarized 13C Imaging, Magn. Reson. Med., in revision. " D. Mayer, Y.S. Levin, R.E. Hurd, G.H. Glover, D.M. Spielman Fast Metabolic Imaging of Systems with Sparse Spectra: Application for Hyperpolarized 13C Imaging, Proc ISMRM, 14th Annual Meeting, Seattle, 2006, submitted.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 介绍： 超极化、代谢活性 MRI 试剂的开发既带来了前所未有的机遇，也带来了新的技术挑战。虽然理论上它不仅允许对底物进行体内成像，而且还允许对下游代谢产物进行体内成像，但纵向磁化强度的衰减需要快速采集方案。对速度的需求与超极化 13C 代谢成像应用中可能出现的稀疏光谱相结合，使得螺旋化学位移成像 (spCSI) 成为该应用的理想候选者。 方法与讨论： 所实现的序列利用稀疏频谱和共振频率的先验知识，通过对谱域中的数据进行欠采样来减少测量时间。因此，必须计算给定数据集的多次重建，其中仅对频率在特定带宽内的分量进行焦点重建，而其他分量则严重模糊（光谱断层合成）。在热平衡极化下，在含有丙氨酸 (Ala)、乳酸盐 (Lac) 和丙酮酸-丙酮酸水合物 C1-C2 酯（具有两个共振，PPE1 和 PPE2）溶液的体模上，在 3 T 下测试序列，所有 C1 羰基位置上的 13C 均富集至 99%。将分别具有单个空间交错 (single-shot spCSI) 和 3 个交错 (3-shot spCSI) 的螺旋 CSI 与相位编码 CSI (FIDCSI) 进行比较。 3 次 spCSI 的所有四种共振的代谢图以及单次 spCSI 的 PPE1 和 PPE2 的代谢图表现出与 FIDCSI 图像相似的分辨率和定位特性。由于混叠共振的信号重叠，单次 spCSI 的 Ala 和 Lac 代谢图包含较小的伪影。 资金来源 “ P41 RR009784，斯坦福大学先进 MR 技术中心，Gary H. Glover， 1995年1月1日-2010年5月31日 “ R01 CA048269，磁共振波谱肿瘤成像，Daniel M. Spielman，1990 年 7 月 23 日-2006 年 7 月 31 日 “ R01 AA012388，酒精中毒的体内扩散和光谱脑成像，Adolf Pefferbaum，8/1/2000-6/30/2010 相关出版物 “D. Mayer、Y.S. Levin、R.E. Hurd、G.H. Glover、D.M. Spielman 稀疏光谱系统的快速代谢成像：超极化 13C 成像的应用，Magn. Reson. Med.，修订中。 “D. Mayer、Y.S. Levin、R.E. Hurd、G.H. Glover、D.M. Spielman 稀疏光谱系统的快速代谢成像：超极化 13C 成像的应用，Proc ISMRM，第 14 届年会，西雅图，2006 年提交。