Background: Biliary atresia (BA) is one of the most common etiologies of cholestasis in infants and toddlers. The most important factor in case of patients’ prognosis is its early diagnosis. There are many diagnostic tools in this field, sonography seems to be the most appropriate and fastest tool in early detecting and differentiating BA from other causes of neonatal cholestasis. The aim of this study was to evaluate the diagnostic value of new ultrasound and Doppler ultrasound methods in BA in infants and toddlers.Methods: This cross-sectional study was performed during a one-year period on 35 infants and toddlers admitted to the gastrointestinal department of Akbar Children's Hospital with suspicion of cholestasis. These children underwent sonography by a radiologist to diagnose BA. All required information was extracted from the hospital records of these children and analyzed after entering the checklist. Data were analyzed using SPSS software version 26.Results: Totally, 35 patients including 18 boys (51.4%) and 17 girls (6.48%) with a mean age of 4/29±4/17 months were enrolled. According to the findings of the analysis, 21 patients (60%) had bile duct atresia and 14 patients (40%) had other diseases. Ultrasound sensitivity in the diagnosis of bile duct atresia was 90%, with an accuracy of 74%, specificity of 50% and positive and negative predictive value of 73% and 77%, respectively. The highest diagnostic value was related to the former hepatic capsular flow.Conclusion: Biliary atresia can be accurately diagnosed by ultrasonography. The high sensitivity and accuracy of ultrasound indicate the appropriateness of this method in diagnosing this diseas
