Investigating Phase-Cycled bSSFP Imaging for Functional Lung Imaging in 2-Year-Olds After Congenital Diaphragmatic Hernia Repair

Motivation: bSSFP-based non-contrast-enhanced imaging is a promising alternative for functional lung imaging in pediatric patients. However, bSSFP acquisitions suffer from magnetic field inhomogeneities. Goal(s): Our goal is to investigate phase-cycled bSSFP acquisitions as a robust alternative in pediatric functional lung imaging. Approach: We acquired dynamic images using conventional and phase-cycled bSSFP acquisitions at 1.5T, from five 2-year-old patients after congenital diaphragmatic hernia repair. The images were non-rigid registered to a reference frame and functional maps were obtained using dynamic mode decomposition technique. Results: We have successfully obtained functional maps in all patients and observed a trend toward improved ventilation map homogeneity using phase-cycled acquisitions. Impact: Pulmonary functional maps obtained via non-contrast-enhanced bSSFP acquisitions may suffer from field inhomogeneity artifacts. Here, we investigate phase-cycled bSSFP imaging in 2-year-old congenital diaphragmatic hernia patients, and show improved robustness, which may be beneficial for lung function assessments.