Regional Gas Exchange Measured by <sup>129</sup> Xe Magnetic Resonance Imaging Before and After Combination Bronchodilators Treatment in Chronic Obstructive Pulmonary Disease.



Hyperpolarized 129 Xe magnetic resonance imaging (MRI) provides a non-invasive assessment of regional pulmonary gas exchange function. This technique has demonstrated that chronic obstructive pulmonary disease (COPD) patients exhibit ventilation defects, reduced interstitial barrier tissue uptake, and poor transfer to capillary red blood cells (RBCs). However, the behavior of these measurements following therapeutic intervention is unknown.


To characterize changes in 129 Xe gas transfer function following administration of an inhaled long-acting beta-agonist/long-acting muscarinic receptor antagonist (LABA/LAMA) bronchodilator.

Study type



Seventeen COPD subjects (GOLD II/III classification per Global Initiative for Chronic Obstructive Lung Disease criteria) were imaged before and after 2 weeks of LABA/LAMA therapy.

Field strength/sequences

Dedicated ventilation imaging used a multi-slice 2D gradient echo sequence. Three-dimensional images of ventilation, barrier uptake, and RBC transfer used an interleaved, radial, 1-point Dixon sequence. Imaging was acquired at 3 T.


129 Xe measurements were quantified before and after LABA/LAMA treatment by ventilation defect + low percent (vendef + low ) and by barrier uptake and RBC transfer relative to a healthy reference population (bar%ref and RBC%ref ). Pulmonary function tests, including diffusing capacity of the lung for carbon monoxide (DLCO ), were also performed before and after treatment.

Statistical tests

Paired t-test, Pearson correlation coefficient (r).


Baseline vendef + low was 57.8 ± 8.4%, bar%ref was 73.2 ± 19.6%, and RBC%ref was 36.5 ± 13.6%. Following treatment, vendef + low decreased to 52.5 ± 10.6% (P < 0.05), and improved in 14/17 (82.4%) of subjects. However, RBC%ref decreased in 10/17 (58.8%) of subjects. Baseline measurements of bar%ref and DLCO were correlated with the degree of post-treatment change in vendef + low (r = -0.49, P < 0.05 and r = -0.52, P < 0.05, respectively).


LABA/LAMA therapy tended to preferentially improve ventilation in subjects whose 129 Xe barrier uptake and DLCO were relatively preserved. However, newly ventilated regions often revealed RBC transfer defects, an aspect of lung function opaque to spirometry. These microvasculature abnormalities must be accounted for when assessing the effects of LABA/LAMA therapy.

Level of evidence






Published Version (Please cite this version)


Publication Info

Mummy, David G, Erika M Coleman, Ziyi Wang, Elianna A Bier, Junlan Lu, Bastiaan Driehuys and Yuh-Chin Huang (2021). Regional Gas Exchange Measured by 129 Xe Magnetic Resonance Imaging Before and After Combination Bronchodilators Treatment in Chronic Obstructive Pulmonary Disease. Journal of magnetic resonance imaging : JMRI, 54(3). pp. 964–974. 10.1002/jmri.27662 Retrieved from

This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.



David Mummy

Assistant Professor in Radiology

Assistant Professor of Radiology in the Driehuys Lab (Xenon MRI Service Center).

My research interest is clinical applications of hyperpolarized Xenon-129 MRI in various pulmonary diseases, including asthma, COPD, and interstitial lung disease.


Bastiaan Driehuys

Professor of Radiology

Our research focuses on magnetic resonance imaging (MRI) research with hyperpolarized 129Xe gas. We are at at the forefront of developing this novel technology for imaging the lungs of patients with pulmonary disease. We currently have multiple, ongoing NIH and industry-sponsored studies invovling this technique. Hyperpolarization is a laser-based process that enhances the MRI signal of xenon gas by a factor of 100,000 to allow for high-resolution, non-invasive MRI of pulmonary function. In addition to our research program, this technology was recently FDA approved and efforts are underway to implement it clinically.

Current studies are applying 129Xe MRI for early diagnosis and monitoring of interstitial and pulmonary vascular diseases. Our group, which is comprised of MRI scientists and radiologists, works closely with colleagues in pulmonary medicine. Our laboratory provides research opportunities to Ph.D., Masters, and medical students as well as select undergraduate students. 


Yuh-Chin Tony Huang

Professor of Medicine

Closed loop ventilation
Environmental medicine
Oxidative lung injury
Hyperpolarized 129Xe MRI and regional lung function

Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.