Abstract | PURPOSE:
Chronic obstructive pulmonary disease ( COPD) is an irreversible lung disease characterized by small- airway obstruction and alveolar-airspace destruction. Hyperpolarized 129 Xe diffusion MRI of lung is a promising biomarker for assessing airspace enlargement, but has yet to be validated by direct comparison to lung histology. Here we have compared diffusion measurements of hyperpolarized ( HP) 129 Xe in explanted lungs to regionally matched morphological measures of airspace size. METHODS: Explanted lungs from five COPD patients and two idiopathic pulmonary fibrosis (IPF) patients were imaged using MRI with hyperpolarized 129 Xe using a two-b-value gradient-echo diffusion sequence, and 34 histological samples were taken from these lungs for quantitative histology. Mean-linear-intercept (Lm ) was compared with spatially matched measures of apparent diffusion coefficient (ADC) from 129 Xe MRI. RESULTS: The mean ADC from COPD lung samples was 0.071 ± 0.011 cm2 /s, and for IPF lungs was 0.033 ± 0.001 cm2 /s (P < 10-15 between groups). The mean Lm in COPD samples was 0.076 ± 0.027 cm and 0.041 ± 0.004 cm in IPF (P = 2.7 × 10-7 between groups). The Pearson-correlation between ADC and Lm measurements was r = 0.59. CONCLUSIONS: Diffusion MRI of HP 129 Xe quantifies regional airspace enlargement in COPD. 129 Xe ADC showed much less overlap between groups than quantitative histology, consistent with our past experience with 3 He diffusion MRI in COPD. Magn Reson Med 77:265-272, 2017. © 2016 Wiley Periodicals, Inc.
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Authors | Robert P Thomen, James D Quirk, David Roach, Tiffany Egan-Rojas, Kai Ruppert, Roger D Yusen, Talissa A Altes, Dmitriy A Yablonskiy, Jason C Woods |
Journal | Magnetic resonance in medicine
(Magn Reson Med)
Vol. 77
Issue 1
Pg. 265-272
(01 2017)
ISSN: 1522-2594 [Electronic] United States |
PMID | 26778748
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural)
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Copyright | © 2016 Wiley Periodicals, Inc. |
Chemical References |
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Topics |
- Adult
- Aged
- Diffusion Magnetic Resonance Imaging
(methods)
- Female
- Histocytochemistry
(methods)
- Humans
- Idiopathic Pulmonary Fibrosis
(diagnostic imaging)
- Image Processing, Computer-Assisted
(methods)
- Lung
(chemistry, diagnostic imaging)
- Male
- Middle Aged
- Phantoms, Imaging
- Pulmonary Disease, Chronic Obstructive
(diagnostic imaging)
- Xenon Isotopes
(chemistry)
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