Tracheal agenesis with tracheoesophageal fistulae: fetal MRI diagnosis with confirmation by ultrasound during an ex utero intrapartum therapy (EXIT) delivery and postdelivery MRI.

Tracheal agenesis is a rare and essentially lethal anomaly with divergent prenatal imaging findings depending on the presence or absence of a tracheoesophageal fistula. All prenatally diagnosed cases of tracheal agenesis reported to date have not had a tracheoesophageal fistula and presented with thoracoabdominal findings similar to congenital high airway obstruction syndrome. We present the case of a 32-week gestation fetus with rapid onset of polyhydramnios and no persistent findings of congenital high airway obstruction syndrome that was ultimately diagnosed with tracheal agenesis plus tracheoesophageal fistula by fetal MRI. Additionally, we present the novel uses of intraoperative US during a staged ex utero intrapartum therapy delivery and postdelivery MRI, facilitated by proximity within the neonatal ICU, to confirm diagnosis and direct patient management while minimizing unnecessary investigations.