C108-17 Xenon MRI Ventilation Impairment Correlates to Quality of Life at School Age for Very Pre-term Children

Rationale Being born very pre-term increases the risk of pulmonary sequelae during infancy, and emerging evidence suggests lung function impairment can persist into adulthood. However, the progression of these issues remains unclear. We used xenon MRI to sensitively assess ventilation in school-age children born very pre-term to better understand the prevalence, severity, and contributing factors of ventilation abnormalities and their relationship to quality of life. Methods This population-based, prospective cohort included 126 six-year-olds (100 very pre-term, 26 term controls). BPD severity was graded at infancy (very pre-term: 50% with no BPD, 27% with grade 1, 18% with grade 2, and 5% with grade 3 BPD.) and obtained from medical records. At 6 years of age, subjects underwent same-day MRI, spirometry, and the St. George Respiratory Questionnaire (SGRQ). Xenon ventilation was acquired using a 2D coronal spiral MRI covering the thoracic cavity. Spirometry and ventilation images were categorized by data quality (unusable, usable, acceptable) and ventilation was normalized to median signal intensity. We calculated mean ventilation, coefficient of variation, and percentage of lung classified as ventilation defect (VDP; ≥2 standard deviations below term control ventilation distribution). Results Xenon MRI yielded higher rates of acceptable (69% vs 8%; P < 0.001) and usable or better (93% vs 75%; P = 0.002) quality than spirometry. In subjects with acceptable data, xenon ventilation correlated best with FEV1/FVC (ρ=-0.72; P < 0.05). Whole lung mean ventilation intensity was slightly reduced in very pre-term children (0.997 vs 0.992; P = 0.03). VDP differed across control, very pre-term, and BPD groups (P = 0.03), with higher VDP in BPD vs controls (4.8% vs 2.6%; P = 0.03). VDP also differed across BPD severity (P = 0.02), with grade 2 BPD showing increased VDP (5.9%) compared to controls (2.6%) and very pre-term (2.9%) without BPD (P ≤ 0.4). Ventilation mean and VDP correlated with gestational age (ρ = 0.32; P < 0.01), BPD severity (ρ = 0.30; P < 0.02), parent-reported health (ρ=-0.24; P < 0.03), and SGRQ scores (ρ = 0.27 and 0.23; P < 0.03). Abnormal VDP was present in 14% of all very pre-term children and increased with BPD severity (6% without BPD, 14% grade 1, 29% grade 2, 50% grade 3; P = 0.02). Conclusions Xenon ventilation MRI detected airway obstruction in prematurity-associated lung disease at 6 years, with higher sensitivity and success rates than spirometry; obstruction increased with BPD severity. Xe MRI enables detection of early obstruction, before severe functional decline, and may support treatment monitoring to improve pulmonary outcomes. Ventilation abnormalities appear to significantly impact reported quality of life. This abstract is funded by: NIH