Quantitative 1H-magnetic resonance spectroscopy of human brain:: Influence of composition and parameterization of the basis set in linear combination model-fitting
Quantitative 1H-magnetic resonance spectroscopy of human brain:: Influence of composition and parameterization of the basis set in linear combination model-fitting
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DOI：
10.1002/mrm.10246
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发表时间：
2002-09-01
影响因子：
3.3
通讯作者：
Kreis, R
中科院分区：
文献类型：
--
作者：
Hofmann, L;Slotboom, J;Kreis, R
人脑局部短回波时间 H-1-MR 谱包含许多低分子量代谢物的贡献和大分子的基线贡献。比较了两种对此类光谱进行建模的方法，并提出了针对再现性进行优化的数据采集序列。建模依赖于先验知识约束和代谢物谱的线性组合。研究的是通过基础参数化可以获得什么，即将基础光谱描述为参数线形的总和。还研究了基础成分和添加实验测量的大分子基线的影响。在评估 40 名受试者的 64 个人类灰质和白质光谱时，两种拟合方法都得出了定量相似的值、模型偏差、误差估计和再现性。参数化基函数的主要优点是可以单独评估拟合参数，将子组谱视为独立的部分，以及纳入与直接代谢物模型的偏差。结果发现，在比较患者队列时，所使用的 22 种基本代谢物中的大多数可以提供有意义的数据。在单个光谱中，密切相关的代谢物的总和通常更有意义。包含大分子基础成分会导致大多数代谢物的组织含量相对较小，但显着不同。它提供了一种量化可能包含关键临床信息的基线贡献的方法。 @2002 年威利利斯公司
Localized short-echo-time H-1-MR spectra of human brain contain contributions of many low-molecular-weight metabolites and baseline contributions of macromolecules. Two approaches to model such spectra are compared and the data acquisition sequence, optimized for reproducibility, is presented. Modeling relies on prior knowledge constraints and linear combination of metabolite spectra. Investigated was what can be gained by basis parameterization, i.e., description of basis spectra as sums of parametric lineshapes. Effects of basis composition and addition of experimentally measured macromolecular baselines were investigated also. Both fitting methods yielded quantitatively similar values, model deviations, error estimates, and reproducibility in the evaluation of 64 spectra of human gray and white matter from 40 subjects. Major advantages of parameterized basis functions are the possibilities to evaluate fitting parameters separately, to treat subgroup spectra as independent moieties, and to incorporate deviations from straightforward metabolite models. It was found that most of the 22 basis metabolites used may provide meaningful data when comparing patient cohorts. In individual spectra, sums of closely related metabolites are often more meaningful. Inclusion of a macromolecular basis component leads to relatively small, but significantly different tissue content for most metabolites. It provides a means to quantitate baseline contributions that may contain crucial clinical information. @ 2002 Wiley-Liss, Inc.