Mali Ivina, Frizzell Bradie, Haworth Steven, Niedbalski Peter J
Division of Pulmonary, Critical Care, and Sleep Medicine, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
Hoglund Biomedical Imaging Center, University of Kansas Medical Center, Kansas City, Kansas, United States of America.
PLoS One. 2025 Aug 26;20(8):e0331113. doi: 10.1371/journal.pone.0331113. eCollection 2025.
Recent advances to gas exchange hyperpolarized 129Xe MRI (Xe-MRI) have demonstrated that cardiogenic oscillations within the xenon red blood cell (RBC) signal are sensitive to pulmonary disease. Moreover, by implementing keyhole image reconstruction with gas exchange images collected using standard methodology, maps of regional oscillation amplitude can be generated. While such mapping has been demonstrated on a limited basis, validating these maps remains challenging due to the absence of easily measured biomarkers of pulmonary microvascular health. Moreover, as this is a very new technique, each of the previous implementations has used different methodology; it is unclear which of these methods provides optimal measures of regional oscillation amplitude. In this study, we evaluated oscillation mapping using the different published methods to determine which has the best same-day reliability. Because there are no easily obtainable measures of pulmonary vascular health, reliability serves as a valuable endpoint for validating that these maps are sensitive to real pulmonary physiology. We evaluated the same-day reliability of RBC oscillation measures in patients with systemic sclerosis (N = 6) and pulmonary arterial hypertension (PAH; N = 10), using single-time-point data from healthy volunteers (N = 9) to demonstrate "healthy" oscillation amplitude maps. Global measures of RBC oscillation amplitude (intraclass correlation coefficient; ICC = 0.88) had comparable reliability to standard xenon MRI measures (ICC ≥ 0.82). When examining oscillation mapping, some regional features showed disagreement across scans, but reliability of overall means was strong (ICC ≥ 0.86). Moreover, we show that recent advances in oscillation amplitude mapping for generating both amplitude and phase can provide equivalent maps to those methods that only provide amplitude. Overall, our findings demonstrate that Xe-MRI oscillation mapping has strong reliability when using optimized methods, even in participants with pulmonary disease.
气体交换超极化129Xe磁共振成像（Xe-MRI）的最新进展表明，氙红细胞（RBC）信号中的心源性振荡对肺部疾病敏感。此外，通过对使用标准方法收集的气体交换图像实施钥孔图像重建，可以生成区域振荡幅度图。虽然这种映射已在有限范围内得到证实，但由于缺乏易于测量的肺微血管健康生物标志物，验证这些图仍然具有挑战性。此外，由于这是一项非常新的技术，之前的每一次实施都使用了不同的方法；目前尚不清楚这些方法中哪一种能提供区域振荡幅度的最佳测量值。在本研究中，我们使用不同的已发表方法评估振荡映射，以确定哪种方法具有最佳的同日可靠性。由于没有易于获得的肺血管健康测量方法，可靠性是验证这些图对真实肺生理敏感的一个有价值的终点。我们使用健康志愿者（N = 9）的单点数据来展示“健康”振荡幅度图，评估了系统性硬化症患者（N = 6）和肺动脉高压（PAH；N = 10）患者红细胞振荡测量的同日可靠性。红细胞振荡幅度的整体测量值（组内相关系数；ICC = 0.88）与标准氙MRI测量值（ICC≥0.82）具有相当的可靠性。在检查振荡映射时，一些区域特征在不同扫描之间存在差异，但总体平均值的可靠性很强（ICC≥0.86）。此外，我们表明，用于生成幅度和相位的振荡幅度映射的最新进展可以提供与仅提供幅度的方法等效的图。总体而言，我们的研究结果表明，即使在患有肺部疾病的参与者中，使用优化方法时Xe-MRI振荡映射也具有很强的可靠性。
