首页> 外文OA文献 >Correlation chemical shift imaging with low-power adiabatic pulses and constant-density spiral trajectories
【2h】

Correlation chemical shift imaging with low-power adiabatic pulses and constant-density spiral trajectories

机译:相关化学位移成像与低功率绝热脉冲和恒定密度螺旋轨迹

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

In this work we introduce the concept of correlation chemical shift imaging (CCSI). Novel CCSI pulse sequences are demonstrated on clinical scanners for two-dimensional Correlation Spectroscopy (COSY) and Total Correlation Spectroscopy (TOCSY) imaging experiments. To date there has been limited progress reported towards a feasible and robust multivoxel 2D COSY. Localized 2D TOCSY imaging is shown for the first time in this work. Excitation with adiabatic GOIA-W(16,4) pulses (Gradient Offset Independent Adiabaticity Wurst modulation) provides minimal chemical shift displacement error, reduced lipid contamination from subcutaneous fat, uniform optimal flip angles, and efficient mixing for coupled spins, while enabling short repetition times due to low power requirements. Constant-density spiral readout trajectories are used to acquire simultaneously two spatial dimensions and f2 frequency dimension in (kx,ky,t2) space in order to speed up data collection, while f1 frequency dimension is encoded by consecutive time increments of t1 in (kx,ky,t1,t2) space. The efficient spiral sampling of the k-space enables the acquisition of a single-slice 2D COSY dataset with an 8 × 8 matrix in 8:32 min on 3 T clinical scanners, which makes it feasible for in vivo studies on human subjects. Here we present the first results obtained on phantoms, human volunteers and patients with brain tumors. The patient data obtained by us represent the first clinical demonstration of a feasible and robust multivoxel 2D COSY. Compared to the 2D J-resolved method, 2D COSY and TOCSY provide increased spectral dispersion which scales up with increasing main magnetic field strength and may have improved ability to unambiguously identify overlapping metabolites. It is expected that the new developments presented in this work will facilitate in vivo application of 2D chemical shift correlation MRS in basic science and clinical studies.
机译:在这项工作中,我们介绍了相关化学位移成像(CCSI)的概念。新的CCSI脉冲序列已在临床扫描仪上进行了二维相关光谱(COSY)和总相关光谱(TOCSY)成像实验的演示。迄今为止,据报道,朝着可行而强大的多体素2D COSY的进展有限。这项工作中首次显示了局部二维TOCSY成像。绝热GOIA-W(16,4)脉冲(梯度偏移独立绝热Wurst调制)激发提供最小的化学位移位移误差,减少了皮下脂肪的脂质污染,均匀的最佳翻转角以及有效的混合耦合旋转,同时允许短重复次由于低功率要求。恒定密度螺旋读出轨迹用于同时获取(kx,ky,t2)空间中的两个空间维和f2频率维,以加快数据收集速度,而f1频率维由(kx ,ky,t1,t2)空间。 k空间的高效螺旋采样使得可以在3 T临床扫描仪上以8:32 min的时间以8×8矩阵采集具有8×8矩阵的单切片2D COZY数据集,这使得在人体上进行体内研究变得可行。在这里,我们介绍在幻影,人类志愿者和脑肿瘤患者中获得的第一个结果。我们获得的患者数据代表了可行且健壮的多体素2D COSY的首次临床演示。与2D J分辨方法相比,2D COZY和TOCSY可提供增加的光谱色散,其随着主磁场强度的增加而扩大,并且可能具有提高的明确识别重叠代谢物的能力。预期这项工作中提出的新进展将促进二维化学位移相关MRS在基础科学和临床研究中的体内应用。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
代理获取

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号