OP10.08: Retrotracheal space width as a potential novel predictor for congenital esophageal atresia

Confirming the patency of upper esophageal lumen is a useful for the prenatal diagnosis of congenital esophageal atresia (CEA), but this cannot be observed except during amniotic fluid swallowing. Our aims were to determine the features of the retrotracheal space (RTS) between the aortic arch and tracheal bifurcation where the esophageal gap is located and the feasibility of measuring this space for the prenatal diagnosis of CEA. A retrospective study, approved by an institutional review board, was conducted. An echogenic space with a cephalocaudal stripe between the trachea and descending aorta was identified. Its minimum distance was measured as RTS width. A regression analysis was performed to investigate the association between RTS width and estimated fetal weight. Z-score was calculated by the equation based on the best-fitting curve. RTS was identified in 256 fetuses; 250 had an anatomically normal esophagus and 6 had CEA. The continuity of the esophageal lumen during amniotic fluid swallowing was confirmed in 78 of the 250 normal fetuses. The upper esophageal pouch was confirmed in 5 of the 6 fetuses with CEA during swallowing. RTS width in normal fetuses was significantly correlated with the estimated fetal weight (R2 = 0.83). The median Z-score among CEA cases was -8.9. Although, the narrowing of RTS is not a definitive finding in the prenatal diagnosis of CEA, performing RTS width assessment as a screening test may prove beneficial when confirming esophageal lumen patency is challenging. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.