Removal of hyperpolarized 129Xe gas-phase contamination in spectroscopic imaging of the lungs
Removal of hyperpolarized 129Xe gas-phase contamination in spectroscopic imaging of the lungs
复制标题
DOI：
10.1002/mrm.27349
复制
发表时间：
2018-12-01
影响因子：
3.3
通讯作者：
Fain, Sean B.
中科院分区：
文献类型：
--
作者：
Hahn, Andrew D.;Kammerman, Jeff;Fain, Sean B.
目的：提出了一种新的技术，用于回顾性估计和去除气相超极化氙-129（HP Xe-129）的图像中溶解在屏障（包括实质肺组织和血浆）和红细胞（RBC）相的HP Xe-129。主要目的是减轻对气体交换测量的RF脉冲性能限制（例如，屏障-气体和RBC-气体比率）。校正气体污染将简化HP E129应用程序在不同硬件性能、扫描仪供应商和型号的站点之间的技术传播。方法：数字肺部模型和人体受试者实验（N = 8例健康人; N = 1例特发性肺纤维化患者）采用3D放射状轨迹和1-点狄克逊光谱成像，以评估减轻屏障和RBC成像伪影的校正方法。TE，图像信噪比，和气体污染水平的性能的依赖性进行了表征。在溶解的相位比的受试者间和受试者内的变化进行了量化和比较，以人类受试者的实验之前和之后correction.Results：气体污染导致图像伪影类似的疾病，在模拟和人类受试者的数据校正后得到缓解;模拟实验的性能与TE不同，但独立的图像信噪比和气体污染的量。人工制品和变化的屏障和红细胞成分在模拟和健康的人肺校正后减少（屏障，P = 0.01; RBC，P = 0.045）。结论：所提出的技术显着减少区域变化的屏障和红细胞的比例，分离使用1点狄克逊的方法，提高了准确性的溶解相HP HPI-129的图像在模拟实验中证实。
Purpose: A novel technique is presented for retrospective estimation and removal of gas-phase hyperpolarized Xenon-129 (HP Xe-129) from images of HP Xe-129 dissolved in the barrier (comprised of parenchymal lung tissue and blood plasma) and red blood cell (RBC) phases. The primary aim is mitigating RF pulse performance limitations on measures of gas exchange (e.g., barrier-gas and RBC-gas ratios). Correction for gas contamination would simplify technical dissemination of HP Xe-129 applications across sites with varying hardware performance, scanner vendors, and models.Methods: Digital lung phantom and human subject experiments (N = 8 healthy; N = 1 with idiopathic pulmonary fibrosis) were acquired with 3D radial trajectory and 1-point Dixon spectroscopic imaging to assess the correction method for mitigating barrier and RBC imaging artifacts. Dependence of performance on TE, image SNR, and gas contamination level were characterized. Inter-and intra-subject variation in the dissolved-phase ratios were quantified and compared to human subject experiments before and after correction.Results: Gas contamination resulted in image artifacts similar to those in disease that were mitigated after correction in both simulated and human subject data; for simulation experiments performance varied with TE, but was independent of image SNR and the amount of gas contamination. Artifacts and variation of barrier and RBC components were reduced after correction in both simulation and healthy human lungs (barrier, P = 0.01; RBC, P = 0.045).Conclusion: The proposed technique significantly reduced regional variations in barrier and RBC ratios, separated using a 1-point Dixon approach, with improved accuracy of dissolved-phase HP Xe-129 images confirmed in simulation experiments.