Using Hyperpolarized Xenon-129 MRI to Quantify Early-Stage Lung Disease in Smokers

Abstract

Rationale and Objectives: Hyperpolarized xenon-129 magnetic resonance (MR) provides sensitive tools that may detect early stages of lung disease in smokers before it has progressed to chronic obstructive pulmonary disease (COPD) apparent to conventional spirometric measures. We hypothesized that the functional alveolar wall thickness as assessed by hyperpolarized xenon-129 MR spectroscopy would be elevated in clinically healthy smokers before xenon MR diffusion measurements would indicate emphysematous tissue destruction. Materials and Methods:Using hyperpolarized xenon-129 MR we measured the functional septal wall thickness and apparent diffusion coefficient of the gas phase in 16 subjects with smoking-related COPD, 9 clinically healthy current or former smokers, and 10 healthy never smokers. All subjects were age-matched and characterized by conventional pulmonary function tests. 11 data sets from younger healthy never smokers were added to determine the age dependence of the septal wall thickness measurements. Results:In healthy never smokers the septal wall thickness increased by 0.04 µm per year of age. The healthy smoker cohort exhibited normal pulmonary function test measures that did not significantly differ from the never-smoker cohort. The age-corrected septal wall thickness correlated well with diffusion capacity for carbon monoxide (R 2 = 0.56) and showed a highly significant difference between healthy subjects and COPD patients (8.8 µm versus 12.3 µm; p < 0.001), but was the only measure that actually discriminated healthy subjects from healthy smokers (8.8 µm versus 10.6 µm; p < 0.006).

Accelerated interleaved spiral‐IDEAL imaging of hyperpolarized 129Xe for parametric gas exchange mapping in humans

“…For parameters affected by lung inflation (i.e., SVR), inspiratory volumes calculated as a fraction of TLC may offer more reproducible quantification . Despite these shortcomings, important parameters of δ, d , and HCT are within the ranges reported previously by Chang et al and others investigating alveolar physiology.…”

Diagnosis and Treatment of Early Chronic Obstructive Lung Disease (COPD)

“…Other imaging modalities have been studied in the assessment of early COPD. Hyperpolarized magnetic resonance imaging (MRI) provides additional information on structural and functional abnormalities of the lung, regional ventilation, alveolar enlargement, and gas diffusion [116]. This technique has potential benefits for detection of patients at risk of COPD [116,117].…”

Molecular Sensing with Host Systems for Hyperpolarized 129Xe

“…By utilizing the sensitivity provided by hp 129 Xe MRI, the progress or changes in the disease patterns are monitored longitudinally in a more controlled way. Clinical lung imaging with Xe is already quite established and provides great anatomical and functional information [ 474 , 475 ]. It also served as a stepping stone for advanced clinical applications for mapping the Xe distribution in other organs like the human brain [ 69 , 476 , 477 ] as well as Xe MRI of the kidneys [ 70 ].…”