Lung MRI scoring reveals persistence of emphysema-like changes in lungs of infants born preterm at (pre)school age.

Background: Chronic lung disease, i.e., bronchopulmonary dysplasia (BPD), is the most prevalent complication after premature birth. Despite the clinical relevance, insight into persisting lung structural changes in BPD in later childhood remains sparse. We therefore assessed lung structural changes by magnetic resonance imaging (MRI) in (pre)school-aged children born before 32 weeks' gestation and compared them to pulmonary characteristics of BPD at near-term age. Methods: (Pre)school-aged children after premature birth with and without BPD underwent 3T MRI without sedation at a median age of 5.8 years (4.3-8.7 years, n=27). Comparative analyses used imaging at near-term age in 88 preterm infants with a subgroup of 16 serial measurements. Standardised image analysis (consensus panel scoring, 5-point Likert scale) of coronal/axial/sagittal T2-weighted single-shot fast-spin-echo sequences obtained scores for the variables "emphysema", "interstitial enhancement", "airway accentuation" and "ventilation inhomogeneity", complemented by transverse (T2) and longitudinal (T1) relaxation-time mapping (n=26), lung volume measurements and follow-up parental questionnaires. Results: MRI scoring revealed persisting emphysema-like changes in children with moderate/severe BPD (p=0.031 versus no BPD). The prevalence was associated with greater immaturity (p=0.018) and in line with an increase in lung volume. In contrast, higher scores for "interstitial enhancement" and "airway accentuation" were not associated with a history of BPD at (pre)school age. Interpretation: Persisting structural changes in the BPD lung are dominated by underlying immaturity and demonstrate an emphysema-like phenotype, potentially fitting the concept of dysanapsis. Lung MRI can inform treatment and monitoring strategies through the provision of additional information on disease characteristics and severity.