Human Brain Proton Metabolite Mapping at Short TE

短 TE 下的人脑质子代谢图谱

• 批准号: 6662532
• 负责人: GERALD B MATSON
• 金额: $ 34.09万
• 依托单位: NORTHERN CALIFORNIA INSTITUTE/RES/EDU
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-30 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6662532
• 关键词: brain disorder diagnosis; brain mapping; brain metabolism; clinical research; computer program /software; glutamates; glutathione; human subject; hydrogen ions; image processing; information systems; lasers; magnetic resonance imaging; mathematical model; measurement; nuclear magnetic resonance spectroscopy; protonation; statistics /biometry; technology /technique development

DESCRIPTION (provided by applicant): A major problem in quantification of proton metabolites obtained by high field magnetic resonance (MR) spectroscopic imaging (MRSI) at short TE is separating the metabolite resonances from the uneven and varying baseline Some of the baseline fluctuations are due to out-of-volume water and lipid signals, while other variations are due to the presence of macromolecules We propose a series of measures to improve the ability to separate metabolite and baseline signals, the most important of which involves obtaining a series of moderate signal-to noise (S/N) spectra at differing TE times with a sequence that includes closely spaced 180 degrees pulses (CP pulse train) to reduce J evolution for strongly coupled spins prior to acquisition This preserves the spectral patterns for strongly coupled resonances at the different TE values even though the signal amplitudes decay due to T2 relaxation Simultaneous fitting of the suite of spectra is expected to enable improved separation of metabolite signals from baseline, and to provide more reliable estimates of metabolite resonance areas A number of additional measures including 1) improved RF pulses, including improvement of hyperbolic secant pulses and a spin echo pulse cascade with immunity to B1 inhomogenicity for the CP pulse train, 2) improved methods of shimming, 3) improved MRSI acquisition sequences, 4) improved methods for processing of metabolite spectra, and 5) improvements for metabolite quantification in institutional units, based on coanalysis with tissue segmented structural MRI data, are planned Finally, a metabolite atlas of normal brain, reflecting regional metabolite levels and variations, will be developed This proposal is coordinated with the partner IRPG proposal for sharing of programs, pulses, data, and information to enhance the research at both sites.

描述（由申请人提供）： 通过高场磁共振（MR）光谱成像（MRSI）在短TE处获得的质子代谢产物定量的主要问题是将代谢物的共振与不均匀和不同的基线分离的基线某些基线波动是由于量不超过的，但由于量的差异是否过多，同时提出了其他范围，同时又提出了对MACR的影响。 to separate metabolite and baseline signals, the most important of which involves obtaining a series of moderate signal-to noise (S/N) spectra at differing TE times with a sequence that includes closely spaced 180 degrees pulses (CP pulse train) to reduce J evolution for strongly coupled spins prior to acquisition This preserves the spectral patterns for strongly coupled resonances at the different TE values even though the signal amplitudes decay due to T2 relaxation Simultaneous fitting of the suite of spectra is expected to enable improved separation of metabolite signals from baseline, and to provide more reliable estimates of metabolite resonance areas A number of additional measures including 1) improved RF pulses, including improvement of hyperbolic secant pulses and a spin echo pulse cascade with immunity to B1 inhomogenicity for the CP pulse train, 2）改进的光滑方法，3）改进的MRSI获取序列，4）改进的代谢光谱处理方法的改进方法，以及5）基于与组织分段的结构MRI数据基于机构单位的代谢产物定量的改进，最终计划的是，是一种正常的大脑，是一个级别的元素，是一种正常的大脑，并构成了正常的大脑，并且是级别的变化。与合作伙伴IRPG提案协调了计划，脉冲，数据和信息，以增强两个站点的研究。