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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Role of transabdominal ultrasound of lung bases and follow-up in premature neonates with respiratory distress soon after birth.

BACKGROUND: Chest radiography has been the traditional method of diagnostic evaluation of patients of hyaline membrane disease (HMD). Lung sonography (USG) has been lately explored as an alternative modality. AIMS: To explore the application of transabdominal USG of lung bases (TASL) in the evaluation of HMD in premature neonates with respiratory distress soon after birth. SETTINGS AND DESIGN: Tertiary care institutional setup. Study duration-18 months. Follow-up-variable, up to 1 month. Prospective descriptive study. MATERIALS AND METHODS: Eighty-eight consecutive patients admitted in the neonatal intensive care unit (NICU) with gestational age <32 weeks having respiratory distress within 6 h of birth were enrolled. The diagnosis of HMD was made if the patient had negative gastric shake test and/or suggestive chest radiograph. TASL was performed in all patients within the first 24 h of life and biweekly subsequently. USG was interpreted as normal, HMD pattern, or broncho-pulmonary dysplasia (BPD) pattern. Biweekly follow-up was done for patients showing HMD till normalization of the sonographic HMD pattern, development of the sonographic BPD pattern, or death/discharge of the neonate from the hospital. RESULTS AND CONCLUSIONS: TASL showed 85.7% sensitivity, 75% specificity, 88.88% positive predictive value, and 69.2% negative predictive value for the diagnosis of HMD. The abnormal sonographic findings on day 14 had 94.1% accuracy for prediction of eventual occurrence of clinical BPD. TASL is complementary to chest radiograph in the diagnosis of HMD. It is also useful for the early prediction of BPD with the potential of reducing the cumulative radiation dose to these neonates.