Dynamic Ventilation 3He-Magnetic Resonance Imaging With Lung Motion Correction: Gas Flow Distribution Analysis

Gast KK, Puderbach MU, Rodriguez I, et al. Dynamic ventilation He-MRI with lung motion correctiongas flow distribution analysis. Invest Radiol 2002;37:126–134. RATIONALE AND OBJECTIVES. Software was developed to correct for lung motion to improve the description of hyperpolarized He gas distribution in the lung. METHODS. Five volunteers were studied by dynamic ventilation He-MRI using an ultrafast FLASH 2D sequence with a temporal resolution of 128 milliseconds. Signal kinetics were evaluated in the trachea and seven parenchymal Regions of Interest. Reference ranges for healthy subjects were defined for motion-corrected and uncorrected images. RESULTS. Motion correction was successfully performed. Reference ranges were 0.11–1.21 seconds for tracheal transit time, 0–0.02 seconds for trachea-alveolar interval, 0.22–0.62 seconds for alveolar rise time and 0–76.6 arbitrary units for alveolar amplitude for motion corrected images, and 0–1.09 seconds, 0–0.11 seconds, 0.26–0.85 seconds, 46.4–99.8 arbitrary units for uncorrected images. CONCLUSIONS. Evaluation of He-distribution in the lung using motion correction of dynamic He-ventilation imaging is feasible and gives more narrow reference ranges.