Hepatic Arterial Diameter Measured with US: Adjunct for US Diagnosis of Biliary Atresia

To prospectively evaluate the accuracy of hepatic artery diameter and hepatic artery diameter-to-portal vein diameter ratio for ultrasonographic (US) diagnosis of biliary atresia, with cholangiographic or clinical information as reference standard.Institutional review board approval and informed consent were obtained. US was performed in 68 neonates and infants with cholestatic jaundice (mean age, 61 days; male-to-female ratio, 38:30). Biliary atresia (n = 38) was confirmed with cholangiography, and hepatitis (n = 30) was diagnosed with clinical (n = 24) or cholangiographic (n = 6) findings. Diameter of the right hepatic artery was measured with US. Right hepatic artery diameter-to-right portal vein diameter ratio was measured to determine relative enlargement of the hepatic artery. As a control group, 17 neonates and infants (mean age, 67 days; male-to-female ratio, 12:5) without jaundice underwent US of the porta hepatis. Statistical analysis was performed to compare US parameters among three groups with one-way analysis of variance. Optimal cutoff values of the hepatic artery diameter and hepatic artery diameter-to-portal vein diameter ratio for biliary atresia diagnosis were obtained with receiver operating characteristic analysis.The diameter of the right hepatic artery in biliary atresia group (1.9 mm +/- 0.4 [standard deviation]) was significantly larger than that in the hepatitis (1.4 mm +/- 0.3) and control (1.2 mm +/- 0.2) groups (P < .001). Hepatic artery diameter-to-portal vein diameter ratio in the biliary atresia group (0.52 +/- 0.12) was larger than that in hepatitis (0.40 +/- 0.07) and in control (0.40 +/- 0.10) groups (P < .001). Optimum cutoff values for diagnosis of biliary atresia were 1.5 mm (sensitivity, 92%; specificity, 87%; accuracy, 89%) for hepatic artery diameter and 0.45 for hepatic artery diameter-to-portal vein diameter ratio (sensitivity, 76%; specificity, 79%; accuracy, 78%).Measurement of hepatic artery diameter can be helpful in the US diagnosis of biliary atresia.