Ultrasound Evaluation of Biliary Atresia Based on Gallbladder Classification: Is 4 Hours of Fasting Necessary?

OBJECTIVES: The aim of this study was to evaluate the influence of fasting time on the ultrasound identification and exclusion of biliary atresia in jaundiced infants through the use of the gallbladder classification scheme and to test the value of the gallbladder classification scheme in the diagnosis of biliary atresia in inexperienced individuals.

METHODS: A total of 188 jaundiced infants were enrolled in this study. All patients received detailed abdominal sonograms. Diagnoses were confirmed via liver biopsy, surgical findings, or follow-up. Infants were grouped into either the fasting group (fasting time ≥ 4 h) or the nonfasting group (fasting time < 4 h). According to the gallbladder classification scheme, the gallbladders were classified into 4 types. The accuracy of diagnosing biliary atresia based on the gallbladder classification scheme was compared between the 2 groups. The gallbladders of 177 infants that were detectable by ultrasonography were used to compare the diagnostic performances between a junior radiologist and an experienced radiologist.

RESULTS: The accuracies in the diagnosis of biliary atresia with the gallbladder classification scheme were 86.3% (82 of 95 patients) for the fasting group and 93.5% (87 of 93 patients) for the nonfasting group (P = .100). The diagnostic accuracies of biliary atresia were 88.7% (157 of 177 patients) for the junior radiologist and 90.4% (160 of 177 patients) for the experienced radiologist (P = .250). The κ value for the agreement between the 2 radiologists was 0.859.

CONCLUSIONS: The performance of gallbladder diagnoses was not influenced by the fasting time with the use of the gallbladder classification scheme. Additionally, the gallbladder classification scheme may help junior radiologists to more effectively identify biliary atresia and nonbiliary atresia.