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Acquiring Hyperpolarized 129Xe Magnetic Resonance Images of Lung Ventilation
Published on: November 21, 2023
Hyperpolarized (3) He and (129) Xe MRI: differences in asthma before bronchodilation
Sarah Svenningsen1, Miranda Kirby, Danielle Starr
1Imaging Research Laboratories, Robarts Research Institute, London, Canada; Department of Medical Biophysics, The University of Western Ontario, London, Canada.
Journal of Magnetic Resonance Imaging : JMRI
|April 17, 2013
Summary
Hyperpolarized xenon-129 MRI detects more ventilation defects in asthma than helium-3 MRI, especially before bronchodilation. Xenon-129 MRI shows greater improvement after salbutamol, revealing subtle airway changes.
Area of Science:
- Pulmonary Medicine
- Medical Imaging
- Respiratory Physiology
Background:
- Asthma is a chronic respiratory disease characterized by airway inflammation and hyperresponsiveness.
- Assessing ventilation defects is crucial for understanding asthma severity and response to treatment.
- Hyperpolarized gas MRI offers a non-invasive method to visualize lung ventilation.
Purpose of the Study:
- To compare the efficacy of hyperpolarized helium-3 ((3) He) and xenon-129 ((129) Xe) MRI in identifying ventilation abnormalities in asthmatic patients.
- To evaluate the changes in ventilation defects before and after salbutamol inhalation using both (3) He and (129) Xe MRI.
Main Methods:
- Seven asthmatic patients underwent spirometry, plethysmography, and MRI with both (3) He and (129) Xe.
- Ventilation defect percent (VDP) and coefficient of variation (COV) were measured before and after salbutamol inhalation.
- Airway wall area percent (WA%) and lumen area (LA) were analyzed in two subjects using CT correlation.
Main Results:
- Pre-salbutamol, (129) Xe MRI showed a significantly greater VDP (8%) compared to (3) He MRI (6%).
- Post-salbutamol, both methods showed improved VDP, with a significantly greater improvement observed with (129) Xe MRI.
- A ventilation defect detected by (129) Xe MRI pre-salbutamol, but not by (3) He MRI, correlated with a remodeled airway.
Conclusions:
- Hyperpolarized (129) Xe MRI is more sensitive than (3) He MRI in detecting ventilation abnormalities in asthma.
- (129) Xe MRI can reveal ventilation defects not apparent with (3) He MRI, particularly before bronchodilation.
- These findings suggest (129) Xe MRI may provide a more comprehensive assessment of ventilation heterogeneity in asthma.
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