Background

Recent studies demonstrate that antifibrotic drugs previously reserved for idiopathic pulmonary fibrosis (IPF) may slow progression in other interstitial lung diseases (ILDs), creating an urgent need for tools that can sensitively assess disease activity, progression, and therapy response across ILDs. Hyperpolarized xenon 129 (¹²⁹Xe) MRI and spectroscopy have provided noninvasive measurements of regional gas-exchange abnormalities in IPF.

Purpose

To assess gas exchange function using ¹²⁹Xe MRI in a group of study participants with nonspecific interstitial pneumonia (NSIP) compared with healthy control participants.

Materials and Methods

In this prospective study, participants with NSIP and healthy control participants were enrolled between November 2017 and February 2020 and underwent ¹²⁹Xe MRI and spectroscopy. Quantitative imaging provided three-dimensional maps of ventilation, interstitial barrier uptake, and transfer into the red blood cell (RBC) compartment. Spectroscopy provided parameters of the static RBC and barrier uptake compartments, as well as cardiogenic oscillations in RBC signal amplitude and chemical shift. Differences between NSIP and healthy control participants were assessed using the Wilcoxon rank-sum test.

Results

Thirty-six participants with NSIP (mean age, 57 years ± 11 [standard deviation]; 27 women) and 15 healthy control participants (mean age, 39 years ± 18; two women) were evaluated. Participants with NSIP had no difference in ventilation compared with healthy control participants (median, 4.4% [first quartile, 1.5%; third quartile, 8.7%] vs 6.0% [first quartile, 2.8%; third quartile, 6.9%]; P = .91), but they had a higher barrier uptake (median, 6.2% [first quartile, 1.8%; third quartile, 23.9%] vs 0.53% [first quartile, 0.33%; third quartile, 2.9%]; P = .003) and an increased RBC transfer defect (median, 20.6% [first quartile, 11.6%; third quartile, 27.8%] vs 2.8% [first quartile, 2.3%; third quartile, 4.9%]; P < .001). NSIP participants also had a reduced ratio of RBC-to-barrier peaks (median, 0.24 [first quartile, 0.19; third quartile, 0.31] vs 0.57 [first quartile, 0.52; third quartile, 0.67]; P < .001) and a reduced RBC chemical shift (median, 217.5 ppm [first quartile, 217.0 ppm; third quartile, 218.0 ppm] vs 218.2 ppm [first quartile, 217.9 ppm; third quartile, 218.6 ppm]; P = .001).

Conclusion

Participants with nonspecific interstitial pneumonia had increased barrier uptake and decreased red blood cell (RBC) transfer compared with healthy controls measured using xenon 129 gas-exchange MRI and reduced RBC-to-barrier ratio and RBC chemical shift measured using spectroscopy.

© RSNA, 2021

Online supplemental material is available for this article.

See also the editorial by Wild in this issue.

中文翻译：

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非特异性间质性肺炎中气体交换异常的超极化 129Xe MRI 和光谱

背景

最近的研究表明，以前用于特发性肺纤维化 (IPF) 的抗纤维化药物可能会减缓其他间质性肺疾病 (ILD) 的进展，因此迫切需要能够敏感地评估 ILD 之间的疾病活动、进展和治疗反应的工具。超极化氙 129 ( ¹²⁹ Xe) MRI 和光谱学提供了 IPF 中区域气体交换异常的无创测量。

目的

^{在一组患有非特异性间质性肺炎 (NSIP) 的研究参与者中使用129} Xe MRI评估气体交换功能，并与健康对照参与者进行比较。

材料和方法

在这项前瞻性研究中，NSIP 参与者和健康对照参与者在 2017 年 11 月至 2020 年 2 月期间入组，并接受了¹²⁹ Xe MRI 和光谱学检查。定量成像提供了通气、间质屏障摄取和转移到红细胞 (RBC) 隔室的三维图。光谱学提供了静态红细胞和屏障摄取隔室的参数，以及红细胞信号幅度和化学位移的心源性振荡。使用 Wilcoxon 秩和检验评估 NSIP 和健康对照参与者之间的差异。

结果

评估了 36 名 NSIP 参与者（平均年龄，57 岁 ± 11 [标准差]；27 名女性）和 15 名健康对照参与者（平均年龄，39 岁 ± 18 岁；2 名女性）。与健康对照组相比，NSIP 参与者在通气方面没有差异（中位数，4.4% [第一个四分位数，1.5%；第三个四分位数，8.7%] vs 6.0% [第一个四分位数，2.8%；第三个四分位数，6.9%]；P = .91)，但他们的屏障吸收率更高（中位数，6.2% [第一个四分位数，1.8%；第三个四分位数，23.9%] vs 0.53% [第一个四分位数，0.33%；第三个四分位数，2.9%]；P = .003 ）和增加的红细胞转移缺陷（中位数，20.6% [第一个四分位数，11.6%；第三个四分位数，27.8%] vs 2.8% [第一个四分位数，2.3%；第三个四分位数，4.9%]；P< .001)。NSIP 参与者的红细胞与屏障峰的比率也降低（中位数，0.24 [第一四分位数，0.19；第三四分位数，0.31] vs 0.57 [第一四分位数，0.52；第三四分位数，0.67]；P < .001）和降低红细胞化学位移（中位数，217.5 ppm [第一四分位数，217.0 ppm；第三四分位数，218.0 ppm] vs 218.2 ppm [第一四分位数，217.9 ppm；第三四分位数，218.6 ppm]；P = .001）。

结论

与使用氙 129 气体交换 MRI 测量的健康对照组相比，患有非特异性间质性肺炎的参与者的屏障摄取增加，红细胞 (RBC) 转移减少，并且使用光谱测量的 RBC 与屏障比和 RBC 化学位移降低。

© 北美放射学会，2021

本文提供在线补充材料。

另见本期 Wild 的社论。