Purpose or Case Report: To evaluate the diagnostic value of preoperative MR cholangiography (MRCP) for the diagnosis of biliary atresia in infants with jaundice.
Methods & Materials: We retrospectively reviewed MRCP performed in infants with jaundice for last two years at our hospital. We measured the maximum diameter of periportal signal change (MR triangular cord) on axial T1-WIs and axial and sagittal T2-WIs. The diameter of hepatic artery and portal vein and the spleen length was also measured. We also evaluated the visibility of common bile duct and the abnormality of gallbladder. On DWI, we measured ADC value in the homogeneous parenchyma of liver and spleen in each patient. We compared the initial chemistry levels and MR findings between the infants diagnosed with biliary atresia (BA group) and the infants with non-surgical etiology (non-BA group).
Results: Totally 29 infants were included with 17 in the BA group and 12 in the non-BA group. The mean age at the time of MRCP was 7 weeks with the range of 1-12 weeks. On chemistry, only the level of gamma-glutamyltranspeptidase was different between the two groups (median, 316 vs. 98 IU/L in BA vs. non-BA group; p<0.001). On MRCP findings, MR triangular cord was thicker in the BA group than in the non-BA group on all the axial T1-WIs (median, 4.2 vs. 3.1 mm; p=0.004), axial T2-WIs (median, 4.3 vs. 2.9 mm; p=0.011), and coronal T2-WIs (median, 5.0 vs. 2.8 mm; p<0.001). Portal vein was larger in the BA group (median, 4.7 vs. 4.0 mm; p=0.030). Common bile duct was visualized only in one infant (1/17, 6%) in the BA group and all twelve infant (12/12, 100%) in the non-BA group (p<0.001). Gallbladder was abnormal in 16 infants (16/17, 94%) in the BA group and no infants in the non-BA group (p<0.001). The BA group had lower ADC value of liver (median, 0.975 vs. 1.200; p=0.008). However, the ADC value of spleen or spleen size was not different between the two groups.
Conclusions: MRCP demonstrated thicker MR triangular cord on both T1- and T2-WIs, larger portal vein size, non-visualized common bile duct, abnormal gallbladder, and decreased ADC value of liver in infants with biliary atresia which showed the possibility of utility of MRCP for the diagnosis of biliary atresiain infants with jaundice.