Free-breathing 3D pulmonary ventilation mapping at 0.55T using Stack-of-Spiral Out-in bSSFP

Motivation: The diagnosis and evaluation of pulmonary dysfunction would benefit from a volumetric approach for ventilation mapping. Goal(s): To demonstrate an efficient and repeatable 3D regional pulmonary ventilation mapping technique, and to compare with existing approaches(2D PREFUL and tidal volume). Approach: We utilize 5-minute free-breathing 3D stack-of-spiral out-in balanced SSFP, constrained reconstruction, and non-rigid registration, to produce 3D maps of regional ventilation. In six healthy volunteers, we compare the proposed method against 2D PREFUL and tidal volume change. Results: The proposed regional ventilation maps show good test-retest repeatability(CoV<5%). Ventilation estimates have strong correlations with PREFUL on a slice-matched basis, and with global tidal volume(R2>0.7). Impact: The proposed approach for 3D regional ventilation mapping requires 5min is feasible and provides consistent measurements and show good agreements with PREFUL in healthy volunteers. This may improve the diagnosis and evaluation of patients with pulmonary dysfunction.