title: Biliary atresia in neonates and infants: triangular area of high signal intensity in the porta hepatis at T2-weighted MR cholangiography with US and histopathologic correlation.
abstract: OBJECTIVE
  To correlate a triangular area of high signal intensity in the porta hepatis on T2-weighted magnetic resonance (MR) cholangiograms of biliary atresia with ultrasonographic (US) and histopathologic findings in a portal mass observed during a Kasai procedure.
  
  
  METHODS
  Twenty-one consecutive neonates and infants (age range, 13-88 days; mean age, 59 days) with cholestasis underwent US and single-shot MR cholangiography. In 12 patients with biliary atresia diagnosed at histopathologic examination, MR cholangiographic findings in the porta hepatis were correlated with US and histopathologic findings in the portal mass.
  
  
  RESULTS
  At US, eight of the 12 patients had round, linear, or tubular hypoechoic portions within a triangular cord; MR cholangiography revealed a triangular area of high signal intensity confined to the porta hepatis. Histopathologic examination of the portal mass revealed a cystic or cleftlike lesion surrounded by loose myxoid mesenchyme and platelike fetal bile ducts. Neither the large cystic lesion without ductal epithelium nor the small cleftlike lesion with scanty epithelium demonstrated bile staining. Similar areas of high signal intensity were not seen on T2-weighted images in the remaining patients (four with biliary atresia and nine with neonatal hepatitis).
  
  
  CONCLUSIONS
  In biliary atresia, T2-weighted single-shot MR cholangiography can show a triangular area of high signal intensity in the porta hepatis that may represent cystic dilatation of the fetal bile duct.
authors.affiliation: Department of Diagnostic Radiology, Severance Hospital, Yonsei University College of Medicine, 134 Shinchon-dong, Seodaemun-ku, Seoul, South Korea. mjkim@yumc.yonsei.ac.kr
authors.forename: M J
authors.initials: MJ
authors.lastname: Kim
authors.forename: Y N
authors.initials: YN
authors.lastname: Park
authors.forename: S J
authors.initials: SJ
authors.lastname: Han
authors.forename: C S
authors.initials: CS
authors.lastname: Yoon
authors.forename: H S
authors.initials: HS
authors.lastname: Yoo
authors.forename: E H
authors.initials: EH
authors.lastname: Hwang
authors.forename: K S
authors.initials: KS
authors.lastname: Chung
mesh_terms: D001646:Bile; D001653:Bile Ducts, Intrahepatic / Q000473:pathology; D001656:Biliary Atresia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D002758:Cholangiography; D015529:Choledochal Cyst / Q000473:pathology; D002779:Cholestasis / Q000175:diagnosis / Q000000981:diagnostic imaging; D004108:Dilatation, Pathologic / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000473:pathology; D004848:Epithelium / Q000473:pathology; D005260:Female; D006505:Hepatitis / Q000175:diagnosis / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008648:Mesoderm / Q000473:pathology; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D019785:Technetium Tc 99m Disofenin; D018608:Ultrasonography, Doppler
chemical_list: D019275:Radiopharmaceuticals; D019785:Technetium Tc 99m Disofenin