Phenotyping bronchopulmonary dysplasia using magnetic resonance imaging.

Bronchopulmonary dysplasia (BPD) is characterized by impaired lung development and persistent respiratory morbidity. BPD comprises three primary phenotypes: parenchymal, airway, and pulmonary vascular disease. Parenchymal disease involves disrupted alveolar growth, emphysema, hyperinflation, inflammation, and fibrosis, leading to impaired gas exchange. Airway disease, including airway malacia and subglottic stenosis, causes airflow obstruction and increased work of breathing. Pulmonary vascular disease involves abnormal vascular remodeling and increased pulmonary vascular resistance, which contributes to the development of pulmonary hypertension. Imaging plays a central role in evaluating these phenotypes which may occur independently or overlap with other phenotypes. Advanced MRI techniques enable non-invasive assessment of lung structure, ventilation, perfusion, airway shape and dynamics, vascular remodeling, and ventricular morphology and function. Imaging-based phenotyping can enhance disease monitoring, risk stratification, and help to inform personalized management strategies in infants with BPD.