Stewart Neil J, Chan Ho-Fung, Hughes Paul J C, Horn Felix C, Norquay Graham, Rao Madhwesha, Yates Denise P, Ireland Rob H, Hatton Matthew Q, Tahir Bilal A, Ford Paul, Swift Andrew J, Lawson Rod, Marshall Helen, Collier Guilhem J, Wild Jim M
Academic Unit of Radiology, University of Sheffield, Sheffield, UK.
Novartis Institutes for Biomedical Research, Cambridge, Massachusetts, USA.
J Magn Reson Imaging. 2018 Mar 5;48(3):632-42. doi: 10.1002/jmri.25992.
To support translational lung MRI research with hyperpolarized Xe gas, comprehensive evaluation of derived quantitative lung function measures against established measures from He MRI is required. Few comparative studies have been performed to date, only at 3T, and multisession repeatability of Xe functional metrics have not been reported.
PURPOSE/HYPOTHESIS: To compare hyperpolarized Xe and He MRI-derived quantitative metrics of lung ventilation and microstructure, and their repeatability, at 1.5T.
Retrospective.
Fourteen healthy nonsmokers (HN), five exsmokers (ES), five patients with chronic obstructive pulmonary disease (COPD), and 16 patients with nonsmall-cell lung cancer (NSCLC).
FIELD STRENGTH/SEQUENCE: 1.5T. NSCLC, COPD patients and selected HN subjects underwent 3D balanced steady-state free-precession lung ventilation MRI using both He and Xe. Selected HN, all ES, and COPD patients underwent 2D multislice spoiled gradient-echo diffusion-weighted lung MRI using both hyperpolarized gas nuclei.
Ventilated volume percentages (VV%) and mean apparent diffusion coefficients (ADC) were derived from imaging. COPD patients performed the whole MR protocol in four separate scan sessions to assess repeatability. Same-day pulmonary function tests were performed.
Intermetric correlations: Spearman's coefficient. Intergroup/internuclei differences: analysis of variance / Wilcoxon's signed rank. Repeatability: coefficient of variation (CV), intraclass correlation (ICC) coefficient.
A significant positive correlation between He and Xe VV% was observed (r = 0.860, P < 0.001). VV% was larger for He than Xe (P = 0.001); average bias, 8.79%. A strong correlation between mean He and Xe ADC was obtained (r = 0.922, P < 0.001). MR parameters exhibited good correlations with pulmonary function tests. In COPD patients, mean CV of He and Xe VV% was 4.08% and 13.01%, respectively, with ICC coefficients of 0.541 (P = 0.061) and 0.458 (P = 0.095). Mean He and Xe ADC values were highly repeatable (mean CV: 2.98%, 2.77%, respectively; ICC: 0.995, P < 0.001; 0.936, P < 0.001). DATA CONCLUSION: Xe lung MRI provides near-equivalent information to He for quantitative lung ventilation and microstructural MRI at 1.5T.
3 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2018.
为支持使用超极化氙气进行的转化性肺部磁共振成像（MRI）研究，需要将衍生的定量肺功能测量值与氦气MRI的既定测量值进行全面评估。迄今为止，仅在3T场强下进行了少数比较研究，且尚未报道氙气功能指标的多时段重复性。
目的/假设：在1.5T场强下比较超极化氙气和氦气MRI得出的肺通气和微观结构的定量指标及其重复性。
回顾性研究。
14名健康非吸烟者（HN）、5名既往吸烟者（ES）、5名慢性阻塞性肺疾病（COPD）患者和16名非小细胞肺癌（NSCLC）患者。
场强/序列：1.5T。NSCLC、COPD患者及部分HN受试者使用氦气和氙气进行了三维平衡稳态自由进动肺通气MRI检查。部分HN、所有ES及COPD患者使用超极化气体核进行了二维多层扰相梯度回波扩散加权肺MRI检查。
从成像中得出通气量百分比（VV%）和平均表观扩散系数（ADC）。COPD患者在四个单独的扫描时段完成了整个MR检查方案以评估重复性。同时进行了当日肺功能测试。
指标间相关性：Spearman系数。组间/核间差异：方差分析/ Wilcoxon符号秩检验。重复性：变异系数（CV）及组内相关系数（ICC）。
观察到氦气和氙气的VV%之间存在显著正相关（r = 0.860，P < 0.001）。氦气的VV%大于氙气（P = 0.001）；平均偏差为8.79%。氦气和氙气的平均ADC之间具有强相关性（r = 0.922，P < 0.001）。MR参数与肺功能测试具有良好的相关性。在COPD患者中，氦气和氙气VV%的平均CV分别为4.08%和13.01%，ICC系数分别为0.541（P = 0.061）和0.458（P = 0.095）。氦气和氙气的平均ADC值具有高度重复性（平均CV分别为2.98%、2.77%；ICC分别为0.995，P < 0.001；0.936，P < 0.001）。数据结论：在1.5T场强下，氙气肺部MRI在定量肺通气和微观结构MRI方面提供了与氦气近乎等效的信息。
3 技术效能2期 《磁共振成像杂志》2018年
