Introduction: The primary aim of this systematic review was to quantify the diagnostic performance of ultrasound, magnetic resonance imaging and amniotic fluid analysis in detecting esophageal atresia prenatally. The secondary aim was to explore the accuracy of individual imaging signs in identifying this anomaly.
Material and methods: MEDLINE, Embase and Cochrane databases were searched. The quality of studies was assessed using the revised tool for the quality assessment of diagnostic accuracy studies. Summary estimates of sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio for the predictive accuracy of ultrasound, magnetic resonance imaging and amniotic fluid analysis in detecting esophageal atresia were computed using the hierarchical summary receiver operating characteristic or DerSimonian-Laird random-effect model, according to the number of studies included in each analysis. PROSPERO registration number: CRD42017055828.
Results: Twenty studies (73 246 fetuses, 1760 affected by esophageal atresia) were included. Overall, prenatal ultrasound had a sensitivity of 31.7%. Only two studies reported all data for diagnostic accuracy; based on these studies, prenatal ultrasound had a sensitivity of 41.9%, a specificity of 99.9%, a positive likelihood ratio of 88.1, a negative likelihood ratio of 0.58 and a diagnostic odds ratio of 153.7. Prenatal ultrasound correctly identified 77.9% of cases with esophageal atresia and 21.9% esophageal atresia with an associated tracheo-esophageal fistula. Polyhydramnios was present in 56.3% of cases affected by esophageal atresia, and a small or absent stomach was identified in 50.0% cases. When performed following a suspicious ultrasound, fetal magnetic resonance imaging had an good overall diagnostic accuracy for esophageal atresia, with a sensitivity of 94.7%, a specificity of 89.3%, a positive likelihood ratio of 8.8, a negative likelihood ratio of 0.06 and a diagnostic odds ratio of 149.3. Finally, amniotic fluid analysis with an esophageal atresia index ≥3 had a sensitivity of 89.9% and a specificity of 99.6% in detecting esophageal atresia.
Conclusions: Ultrasound alone is a poor diagnostic tool for identifying esophageal atresia prenatally, and has a high rate of false positive diagnoses. Magnetic resonance imaging and amniotic fluid analysis have high diagnostic accuracy for esophageal atresia. We would recommend their use following a suspicious ultrasound.
Keywords: amniotic fluid analysis; esophageal atresia; magnetic resonance imaging; prenatal diagnosis; ultrasound.
© 2019 Nordic Federation of Societies of Obstetrics and Gynecology.