Fetal esophageal imaging: Early pregnancy as a window of opportunity

OBJECTIVE: To describe the sonographic appearance of the fetal esophagus during early pregnancy and evaluate the feasibility of imaging the entire esophageal length. In addition, we present a case of disrupted esophageal continuity, subsequently diagnosed with esophageal atresia (EA). METHODS: A prospective observational study of 145 patients. During the early second trimester anomaly scan performed at 12-17 weeks' gestation the entire esophagus was captured in a single sonographic image at the midsagittal plane (one shot technique). Postnatal follow-up of esophageal patency included review of medical records and telephone interviews. RESULTS: Complete visualization of the esophagus (neck to diaphragm) was possible in 144 cases. In 88% of cases the esophagus was demonstrated by transvaginal approach. The time required to obtain the desired view of the esophagus, once the fetus was in an optimal position, was on average 13 s (range: 5-30 s). In one case at 15 weeks' gestation, the cervical segment of the esophagus was demonstrated while the lower thoracic segment was not identified. Subsequently EA was diagnosed. CONCLUSIONS: It is feasible to demonstrate the entire esophagus during early second trimester anomaly scan. An early second trimester anomaly scan may serve as a window of opportunity for EA screening.