Stephanie A Adaikalam1, Nara S Higano2, Jean A Tkach3, Foong Yen Lim4,5, Beth Haberman1,6, Jason C Woods2,3,6, Paul S Kingma7,8,9. 1. The Perinatal Institute, Section of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. 2. Center for Pulmonary Imaging Research, Division of Pulmonary Medicine and Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. 3. Imaging Research Center, Department of Radiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. 4. Divisions of Pediatric General, Thoracic and Fetal Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. 5. Cincinnati Fetal Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. 6. Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA. 7. The Perinatal Institute, Section of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. paul.kingma@cchmc.org. 8. Cincinnati Fetal Center, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA. paul.kingma@cchmc.org. 9. Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA. paul.kingma@cchmc.org.
Abstract
BACKGROUND: Outcomes of infants with congenital diaphragmatic hernia (CDH) are primarily dependent on the severity of pulmonary hypoplasia. It is previously unknown whether postnatal lung growth in infants with CDH represents true parenchymal lung growth or merely an expansion in volume of the existing tissue. We hypothesized that lung volume growth in CDH infants will be accompanied by an increase in lung mass and that CDH infants will demonstrate accelerated catch-up growth of the more hypoplastic lung. METHODS: We used fetal and post-CDH repair MRI of 12 infants to measure lung volume and density, which was used to calculate lung mass. RESULTS: The average increase in right lung mass was 1.1 ± 1.1 g/week (p = 0.003) and the average increase in left lung mass was 1.8 ± 0.7 g/week (p < 0.001). When the ratio of left-to-right lung mass of the prenatal MRI was compared to post-repair MRI, the ratio significantly increased in all infants with average prenatal and post-repair ratios of 0.30 and 0.73, respectively (p = 0.002). CONCLUSION: Lung growth in infants with CDH is indeed growth in lung mass (i.e. parenchyma), and the lungs demonstrate catch-up growth (i.e., increased rate of growth in the more hypoplastic ipsilateral lung).
BACKGROUND: Outcomes of infants with congenital diaphragmatic hernia (CDH) are primarily dependent on the severity of pulmonary hypoplasia. It is previously unknown whether postnatal lung growth in infants with CDH represents true parenchymal lung growth or merely an expansion in volume of the existing tissue. We hypothesized that lung volume growth in CDH infants will be accompanied by an increase in lung mass and that CDH infants will demonstrate accelerated catch-up growth of the more hypoplastic lung. METHODS: We used fetal and post-CDH repair MRI of 12 infants to measure lung volume and density, which was used to calculate lung mass. RESULTS: The average increase in right lung mass was 1.1 ± 1.1 g/week (p = 0.003) and the average increase in left lung mass was 1.8 ± 0.7 g/week (p < 0.001). When the ratio of left-to-right lung mass of the prenatal MRI was compared to post-repair MRI, the ratio significantly increased in all infants with average prenatal and post-repair ratios of 0.30 and 0.73, respectively (p = 0.002). CONCLUSION: Lung growth in infants with CDH is indeed growth in lung mass (i.e. parenchyma), and the lungs demonstrate catch-up growth (i.e., increased rate of growth in the more hypoplastic ipsilateral lung).