Diagnostic accuracy of ultrasonography for the prenatal diagnosis of esophageal atresia and tracheoesophageal fistula

Ultrasound is recommended as a first-line requirement prior to MRI or amniotic fluid analysis, which have high diagnostic accuracy for esophageal atresia (EA). Therefore, the aim of the present prospective study was to evaluate the accuracy of high-performance ultrasound for the prenatal examination of EA/tracheoesophageal fistula (TOF). In total, 64 pregnant women with fetuses suspected of having EA/TOF participated in the study. The gestational age of the fetuses ranged between 16 and 40 weeks, with a mean of 26.33±3.57 weeks. Ultrasound images of the esophagus and trachea on parasternal and para-aortic axis longitudinal and transverse sections were compared with the results of standard postnatal diagnostic tests. Sensitivity and specificity values were determined and a receiver operating characteristic (ROC) curve was generated. Among all the fetuses screened, 16 were suspected of having EA/TOF during the prenatal ultrasonography. In postnatal examinations, 34 cases of EA/TOF were confirmed, corresponding to an EA/TOF incidence of 53.2% (95% CI, 40.2-65.7%). The area under the ROC curve (AUC) was lower for prenatal ultrasonography compared with postnatal diagnostic tests (AUC=0.55; 95% CI, 0.44-0.65). Considering postnatal examination as the gold standard, prenatal ultrasonography had a sensitivity of 29.4% (95% CI, 15.1-47.5%) and a specificity of 80% (95% CI, 61.4-92.3%) for the diagnosis of EA/TOF. In addition, the positive predictive value was 62.5% (95% CI, 35.4-82.8%), the negative predictive value was 50% (95% CI, 35.2-64.8%), the positive likelihood ratio was 1.47 (95% CI, 0.61-3.56) and the negative likelihood ratio was 0.88 (95% CI, 0.67-1.17). The results of the present study indicate that preoperative ultrasound has poor sensitivity but very good specificity for the diagnosis of EA/TOF. The use of ultrasound alone would result in a high rate of a false-positive diagnoses. However, prenatal ultrasonography may be useful as a preliminary screening tool to exclude patients for suspected EA/TOF.