Role of preoperative 3D CT reconstruction for evaluation of patients with esophageal atresia and tracheoesophageal fistula

Abstract

The role of preoperative contrast-enhanced computerized tomography (CT) of chest with three-dimensional (3D) reconstructions was evaluated in neonates with esophageal atresia and tracheoesophageal fistula. This was a prospective study which investigated 30 cases of esophageal atresia with tracheoesophageal fistula. All patients were evaluated preoperatively with contrast-enhanced spiral CT using a low-dose CT protocol. 3D CT reconstruction images were evaluated for the type of esophageal atresia, the distance between the upper and lower esophageal pouches, origin, level and position of the fistula, and the presence or absence of any other cardiac, pulmonary or mediastinal lesions and the findings were correlated with the findings at surgery. The radiation dose for each patient was calculated using the formula-Effective dose (E) = DLP × (E/DLP)age. All the 30 cases had type-C esophageal atresia with tracheoesophageal fistula as per Gross classification. The exact site of the fistula could be identified only in 26 (80 %) cases. The mean gap between the upper pouch and lower fistula was 0.95 ± 0.57 cm (range 0.2-2.8 cm) on CT scan and 1.38 ± 0.61 cm (range 0.5-3.2 cm) at surgery. On statistical analysis, the correlation was found to be significant (p < 0.0001). In addition, lung pathology (consolidation), cardiac pathology and vertebral anomaly were also detected on CT scan in some cases. The mean radiation dose for the neonates who underwent CT chest was calculated to be 1.79 mSv which is significantly high. Though preoperative CT scan of chest has many advantages, it involves significant exposure to ionizing radiation and risk of radiation-induced cancer in the future. Additionally in 20 % of cases, the fistula could not be located on CT scan. The most common variety of esophageal atresia and tracheoesophageal fistula is Gross type C (86 %) that has low to intermediate gap (97 %) and can be anastomosed primarily. Thus, CT scan can provide good anatomical delineation, but may not help in surgical decision making. Hence, performing CT in these cases would unnecessarily expose the neonates to ionizing radiation. Therefore, there is no role for CT scan in the routine preoperative assessment of EA with distal TEF.