Fetal lung-to-head ratio in the prediction of survival in severe left-sided diaphragmatic hernia treated by fetal endoscopic tracheal occlusion (FETO)

Objective The objective of the study was to investigate the value of fetal lung area to head circumference ratio in the prediction of the postnatal outcome in left-sided congenital diaphragmatic hernia treated by fetoscopic endoluminal tracheal occlusion. Study design The lung area to head circumference ratio was measured before fetoscopic endoluminal tracheal occlusion in 28 fetuses with congenital diaphragmatic hernia at 25 to 29 weeks. Regression analysis was used to investigate the effect on survival of lung area to head circumference ratio, gestation at fetoscopic endoluminal tracheal occlusion, gestation at delivery, preterm amniorrhexis following fetoscopic endoluminal tracheal occlusion, and prenatal removal of the balloon. Results The median lung area to head circumference ratio prior to fetoscopic endoluminal tracheal occlusion was 0.7 (range 0.5 to 0.9). The median gestation at delivery was 34 (range 27 to 39) weeks, and there were 16 survivors (57%). Only lung area to head circumference ratio provided significant prediction of survival, which increased from 17% for lung area to head circumference ratio of 0.4 to 0.5 to 62% for lung area to head circumference ratio of 0.6 to 0.7 and 78% for lung area to head circumference ratio of 0.8 to 0.9. Conclusion In congenital diaphragmatic hernia treated by fetoscopic endoluminal tracheal occlusion, postnatal survival can be predicted by the lung area to head circumference ratio measured prior to the procedure.