Pulmonary vascular growth in bronchopulmonary dysplasia using magnetic resonance imaging

Bronchopulmonary dysplasia (BPD) is the most common chronic lung disorder associated with premature infants, particularly those who have required long-term mechanical ventilation and were exposed to supplemental oxygen.1 It is characterized by an interplay of pulmonary fibrosis, atelectasis, and emphysema coupled with airway collapse and pulmonary hypertension.2 BPD has lifelong pulmonary morbidity and the prevalence has remained unchanged over the past 2 decades3 with patients needing repeat hospitalizations,4 having exercise intolerance,5 and an earlier development of a chronic obstructive pulmonary disease phenotype.6 Emerging evidence suggests that vascular remodeling, aberrant angiogenesis, and impaired pulmonary perfusion may play a significant role in the pathogenesis of BPD.7 However, the influence of vascular remodeling on clinical outcomes of infants admitted to the neonatal ICU with BPD remains poorly understood. Methods for evaluation of distal pulmonary vasculature are limited. Currently, echocardiography findings are used as surrogate markers for pulmonary vascular disease and pulmonary hypertension in patents with BPD. Unfortunately, echocardiography does not directly evaluate smaller, more distal vascular structures. We previously used magnetic resonance imaging (MRI) to evaluate pulmonary vascularity in a small cohort of premature infants with BPD and found that pulmonary vascularity correlated with respiratory outcomes.8