Value of hepatic subcapsular flow by color Doppler ultrasonography in the diagnosis of biliary atresia

Abstract

Background and aim: Diagnosis of biliary atresia (BA), particularly distinguishing it from other causes of neonatal cholestasis (NC), is challenging. Ultrasonography is a helpful investigation when evaluating NC. The aim was to determine the value of color Doppler ultrasound, particularly hepatic subcapsular flow, as a possible tool in early discrimination of BA from other causes of NC.

Methods: Ultrasonographic and color Doppler findings of 27 BA patients were compared with that in 27 non-BA cholestasis patients and a control group of 22 non-hepatic neonates.

Results: Hepatic artery diameter was significantly higher in BA (2.48 ± 0.55 mm) than that in non-BA group (1.91 ± 0.63 mm) (P = 0.001) and the control group (1.6 ± 0.47 mm) (P < 0.0001), while there were no statistically significant difference between BA and non-BA groups as regards portal vein diameter and flow, hepatic vein flow, and hepatic artery resistance index. The frequency of hepatic subcapsular flow was significantly higher in BA than that in non-BA group (96.3% vs 3.7%; P < 0.0001), while it was not detected in any of the non-hepatic control group. The presence of hepatic subcapsular flow had 96.3% sensitivity and specificity in predicting BA.

Conclusions: Color Doppler ultrasound findings could help significantly in discriminating BA from other causes of NC, among which hepatic subcapsular flow had the best performance. Considering the young age of BA patients (61.8 ± 15.1 days), hepatic subcapsular flow can help in early diagnosis of BA and prevent the delay in surgical correction.