CEST signal at 2ppm (CEST@2ppm) from Z-spectral fitting correlates with creatine distribution in brain tumor.
CEST signal at 2ppm (CEST@2ppm) from Z-spectral fitting correlates with creatine distribution in brain tumor.
复制标题
来自Z频谱拟合的2ppm（CEST@2ppm）处的CEST信号与脑肿瘤中的肌酸分布相关。
DOI：
10.1002/nbm.3216
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发表时间：
2015-01
影响因子：
2.9
通讯作者：
Reddy, Ravinder
中科院分区：
文献类型：
--
作者：
Cai, Kejia;Singh, Anup;Poptani, Harish;Li, Weiguo;Yang, Shaolin;Lu, Yang;Hariharan, Hari;Zhou, Xiaohong J.;Reddy, Ravinder
关键词：
通常，多种成分，如水直接饱和（DS），磁化转移（MT），化学交换饱和转移（CEST）和脂肪核奥弗豪泽效应（NOE）有助于Z-谱。传统的基于非对称分析的CEST定量方法可能会由于半固态MT的非对称性和位于Z-谱单侧的脂肪族NOE效应而导致定量误差。将各个贡献者拟合到Z谱可以改善每个分量的量化。在这项研究中，我们的目标是表征多种可交换的成分，从颅内肿瘤模型使用简化的Z-光谱拟合方法。在该方法中，将在低饱和RF振幅（50 Hz）下采集的Z光谱建模为对应于NOE、MT效应、本体水、酰胺质子转移（APT）效应和位于+2ppm的CEST峰（称为CEST@2ppm）的五个洛伦兹函数的总和。通过逐像素拟合，定量总结了这五种成分在脑肿瘤和正常脑组织中的区域变化。与正常脑组织相比，在脑肿瘤中观察到APT效应增加，NOE降低和CEST降低@2ppm。此外，CEST@2ppm随着肿瘤进展而降低。发现CEST@2ppm与质子磁共振波谱（1H-MRS）定量的肌酸浓度相关。基于相关曲线，定量肌酸对CEST@2ppm的贡献。CEST@2ppm信号可能是体内肌酸（重要的生物能量学标志物）的新成像替代物。鉴于其非侵入性的性质，这种CEST MRI方法可能在癌症生物能量学中具有广泛的应用。
In general, multiple components such as water direct saturation (DS), magnetization transfer (MT), chemical exchange saturation transfer (CEST) and aliphatic nuclear overhauser effect (NOE) contribute to Z-spectrum. The conventional CEST quantification method based on asymmetrical analysis may lead to quantification errors due to the semi-solid MT asymmetry and the aliphatic NOE effect located on single side of the Z-spectrum. Fitting individual contributors to the Z-spectrum may improve the quantification of each component. In this study, we aim to characterize the multiple exchangeable components from an intracranial tumor model using a simplified Z-spectral fitting method. In this method, the Z-spectrum acquired at low saturation RF amplitude (50 Hz) was modeled as the summation of five Lorentzian functions that correspond to NOE, MT effect, bulk water, amide proton transfer (APT) effect and a CEST peak located at +2ppm, called CEST@2ppm. With the pixel-wise fitting, the regional variation of these five components in the brain tumor and the normal brain tissue were quantified and summarized. Increased APT effect, decreased NOE and reduced CEST@2ppm were observed in the brain tumor compared to the normal brain tissue. Additionally, the CEST@2ppm decreased with tumor progression. The CEST@2ppm was found to correlate with the creatine concentration quantified with proton magnetic resonance spectroscopy (1H-MRS). Based on the correlation curve, the creatine contribution to the CEST@2ppm was quantified. The CEST@2ppm signal could be a novel imaging surrogate for in vivo creatine, the important bioenergetics marker. Given its noninvasive nature, this CEST MRI method may have broad applications in cancer bioenergetics.
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DOI：
10.1007/978-1-4614-4989-8_6
发表时间：
2013-01-01
期刊：
OXYGEN TRANSPORT TO TISSUE XXXIV
影响因子：
--
作者：
Cai, Kejia;Xu, He N.;Li, Lin Z.
通讯作者：
Li, Lin Z.
影响因子：
3.3
作者：
Jones, Craig K.;Polders, Daniel;Hua, Jun;Zhu, He;Hoogduin, Hans J.;Zhou, Jinyuan;Luijten, Peter;van Zijl, Peter C. M.
通讯作者：
van Zijl, Peter C. M.
影响因子：
2.4
作者：
CHANG, L;BOOTH, RA;JENDEN, D
通讯作者：
JENDEN, D
影响因子：
1.4
作者：
Bleyer, WA
通讯作者：
Bleyer, WA
影响因子：
3.3
作者：
Desmond, Kimberly L.;Moosvi, Firas;Stanisz, Greg J.
通讯作者：
Stanisz, Greg J.