Dependence of diffusion and ventilation metrics on hyperpolarized 129Xe lung MRI with demographics in healthy volunteers

Motivation: The normal ranges of pulmonary 129Xe diffusion and ventilation MRI metrics are not well established. Goal(s): To evaluate the influence of age, sex, height, and weight on 129Xe-MRI diffusion and ventilation metrics in a cohort of healthy volunteers. Approach: 3D diffusion-weighted SPGR and 3D SSFP ventilation images were acquired in 65 and 42 healthy volunteers, respectively. Results: Over the age range of 9 to 70 years, mean diffusion coefficients and alveolar dimensions were strongly correlated with age (Spearman r=0.73, p < 0.0001). The ventilation defect percentage was not correlated with any demographics, but some markers of ventilation heterogeneity increase significantly with age. Impact: Defining normal ranges for diffusion and ventilation 129Xe MRI metrics is important for clinical interpretation. Results show a significant increase of alveolar dimensions with age and provide an upper limit of normal for the ventilation defect percentage metric.