Assessment of fetal lung volumes and liver herniation with magnetic resonance imaging in congenital diaphragmatic hernia

Objective: We evaluated the use of fetal magnetic resonance imaging in predicting outcomes after ultrasonographic diagnosis of left-sided congenital diaphragmatic hernia. Study Design: Forty-one pregnant women carrying fetuses with congenital diaphragmatic hernia underwent 43 magnetic resonance imaging scans. Lung volumes were calculated by summing the areas on 6-mm axial sections. The presence or absence of liver herniation was noted. A liver/diaphragm ratio was obtained by using the distances from the superior aspect of the liver and the diaphragmatic remnant to the apex of the chest. Results: Mean gestational age was 26 weeks and overall survival was 59%. Neither right, left, nor total lung volume measurements were predictive of survival. Liver herniation into the left side of the chest was predictive of outcome at P< .05. The liver/diaphragm ratio was predictive of outcome at P = .03. Conclusion: Fetal magnetic resonance imaging permits calculation of lung volumes, but these volumes are not predictive of outcome. However, both the presence of liver herniation and the volume of liver within the chest, as reflected by the liver/diaphragm ratio, help predict outcome in left-sided congenital diaphragmatic hernia. (Am J Obstet Gynecol 2000;183:1067-9.)