MR Imaging of Pulmonary Surfactant Distribution in a Preclinical Neonatal Lung Model

The administration of exogenous surfactant is essential for many premature infants to compensate for pulmonary immaturity and the absence of endogenous surfactant at birth. Exogenous surfactant delivery techniques are continually being refined to improve the management of these infants, with the goal of increasing therapeutic efficacy and decreasing the invasiveness of delivery protocols. Imaging is one of the tools available to achieve these goals. In this study, we established and applied an magnetic resonance imaging (MRI) protocol in a rabbit animal model to determine the intrapulmonary distribution of surfactant solution administered by the clinical reference method. The protocol was applied to an ex vivo model of isolated thorax from non-valued food industry by-products. The protocol made it possible to image surfactant biodistribution with isotropic spatial resolution in the millimeter range, to determine surfactant distribution between the main airways and distal lung regions where alveoli are present using automated segmentation techniques, and to quantitatively map the distribution of the administered surfactant solution.