Abstract #2495

Relative Recirculation Abnormalities in Collapsed Lung: A Metric for Vascular Tortuosity?

Christopher K. Macgowan^1,2, Shengping Wu², Rogerio Tessler³, Jaques Belik^2,4, Andrea Kassner^2,5

¹Medical Biophysics, University of Toronto, Toronto, ON, Canada; ²Physiology and Experimental Medicine, Hospital for Sick Children, Toronto, ON, Canada; ³Pediatrics, Pontifcia Universidade Catolica do Rio Grande do Sul, Rio Grande do Sul, Brazil; ⁴Pediatrics, University of Toronto, Toronto, ON, Canada; ⁵Medical Imaging, University of Toronto, Toronto, ON, Canada

Respiratory distress syndrome (RDS) affects approximately 1% of newborn children and is the leading cause of death in pre-term infants. It is characterized by regional lung collapse (atelectasis) resulting from low surfactant production in the immature lung. Atelectasis results in shortening and folding of the alveolar walls, leading to abnormal and tortuous microvasculature. Relative recirculation (rR) obtained from dynamic perfusion MRI has been proposed previously as a metric of microvessel tortuosity. Our findings show increased rR values in the collapsed lung which we believe is associated with acute architectural remodeling.