Direct imaging of pulmonary gas exchange in vivo with hyperpolarized xenon MRI

Motivation: Hyperpolarized 129Xe gas MRI is a promising technique for assessing pulmonary abnormalities, yet distinguishing signals from RBCs and TP is challenging. Goal(s): We aimed to develop a method to simultaneously image 129Xe in lung airspace and either TP or RBC for accurate gas exchange assessment. Approach: Employing high selective RF pulses for selective excitation of 129Xe in TP and RBCs, while capturing lung airspace signals, and using a 3D radial sequence for acquisition. Results: The method demonstrated feasibility in a rat model with pulmonary fibrosis, revealing significant differences in RBC/TP, RBC/Gas and TP/Gas ratios between fibrosis and control groups. Impact: The proposed gas exchange MRI method improves diagnosis of lung diseases by accurately assessing gas exchange function in the lungs.