Sci—Thurs AM: YIS—06: Longitudinal Hyperpolarized 3He Magnetic Resonance Imaging of Chronic Obstructive Pulmonary Disease



RATIONALE: To date, no studies have quantitatively evaluated chronic obstructive pulmonary disease (COPD) longitudinally using hyperpolarized helium-3 (3He) magnetic resonance imaging (MRI). OBJECTIVES: To evaluate COPD longitudinally using hyperpolarized 3He MRI and to determine correlations between the changes in 3He MRI ventilation defect volume (VDV), apparent diffusion coefficients (ADC) and changes in pulmonary function. METHODS: Hyperpolarized 3He MRI, spirometry and plethysmography were performed in 15 COPD ex-smokers (n=9 stage II and n=6 stage III/IV COPD) at baseline and 26±2 months later. 3He MRI ADC values were calculated from 3He MRI diffusion-weighted images and 3He VDV were generated after manual segmentation of 3He MRI spin-density images. MEASUREMENTS AND MAIN RESULTS: At follow-up, COPD subjects showed significant increases in 3He MRI CS VDV (p=.01), WL VDV (p=.04), as well as ADC (p=.003) and no significant change in FEV1 (p=.91). There was a significant correlation between changes in FEV1%predicted and changes in CS VDV (r=.66, p=.007), however no significant correlations between smoking history (years non-smoker at baseline) and changes in 3He MRI measurements or FEV1 was found. CONCLUSIONS: For COPD ex-smokers, 3He MRI VDV and ADC measurements worsened significantly but there was no significant change in FEV1, suggesting higher sensitivity of hyperpolarized 3He MRI to COPD changes over short periods of time.