Differential patterns of prenatal ipsilateral and contralateral lung growth in cases of isolated left-sided congenital diaphragmatic hernia

Objective: The aim of this research was to compare the impact of varying degrees of visceral herniation on the growth rates of the contralateral and ipsilateral fetal lungs in cases of isolated left-sided congenital diaphragmatic hernia (CDH). Methods: Data were retrieved from 58 fetuses with isolated left-sided CDH undergoing magnetic resonance imaging studies at both mid-gestation (20-30weeks) and late-gestation (>30weeks) time points. The growth of the right and left lungs (ΔLV-R and ΔLV-L) was calculated. The impact of the degree of visceral herniation on the growth disparity between the right and left lungs was then compared. Results: Measurable growth occurred in both lungs between the mid-gestation and late-gestation time points in each group. The ΔLV-R exhibited a strong correlation with ΔLV-L. However, the right lung grew significantly faster than the left lung (ΔLV-R=1.36 vs ΔLV-L=0.17mL/week, P<0.001). A higher degree of visceral herniation appeared to decrease the growth rate disparity by progressive limitation of the growth of the right lung. Conclusion: The contralateral lung retains the potential to grow faster than the ipsilateral lung during the third trimester. A higher degree of visceral herniation places progressive limitations on contralateral lung growth thereby diminishing the growth rate disparity between the right and left lungs.