title: Making the diagnosis of biliary atresia using the triangular cord sign and gallbladder length.
abstract: BACKGROUND
  To evaluate the accuracy and utility of the triangular cord sign and gallbladder length in diagnosing biliary atresia by sonography.
  
  
  METHODS
  Sixty fasted infants with cholestatic jaundice aged 2-12 weeks were examined sonographically using a 5-10 MHz linear array transducer, focusing on the triangular cord sign (as described by Choi et al. [1]), the gallbladder, and ducts. The triangular cord is defined as a triangular or tubular echogenic density seen immediately cranial to the portal vein bifurcation; it represents the fibrotic remnant of the obliterated cord in biliary atresia. The findings were blinded to blood chemistry, (99 m)Tc-DISIDA hepatobiliary scintigraphy, and liver biopsy. Diagnosis of biliary atresia was confirmed at surgery and histology. Non-biliary atresia infants resolved medically. Comparative charges of the various investigations was made.
  
  
  RESULTS
  ++ Twelve infants had biliary atresia, and ten demonstrated a definite triangular cord. The two false-negatives had small or nonvisualized gallbladders. No false-positives were recorded. Gallbladder length ranged from 0-1.45 cm with a mean of 0. 52 cm in biliary atresia compared to a mean of 2.39 cm in nonbiliary atresia infants. (99 m)Tc-DISIDA hepatobiliary scintigraphy showed no excretion (false-positive) in 23 % of nonbiliary atresia cases. Scintigraphy and liver biopsy charges were 2 and 6 times that of sonography, respectively.
  
  
  CONCLUSIONS
  The triangular cord sign and gallbladder length together are noninvasive, inexpensive, and very useful markers for biliary atresia.
authors.affiliation: Department of Diagnostic Imaging, Kandang Kerbau Women's and Children's Hospital, 100 Bukit Timah Road, Singapore.
authors.forename: A P
authors.initials: AP
authors.lastname: Tan Kendrick
authors.forename: K B
authors.initials: KB
authors.lastname: Phua
authors.forename: B C
authors.initials: BC
authors.lastname: Ooi
authors.forename: R
authors.initials: R
authors.lastname: Subramaniam
authors.forename: C E
authors.initials: CE
authors.lastname: Tan
authors.forename: A S
authors.initials: AS
authors.lastname: Goh
mesh_terms: D017734:Bile Ducts, Extrahepatic / Q000002:abnormalities* / Q000000981:diagnostic imaging; D001656:Biliary Atresia / Q000150:complications / Q000175:diagnosis / Q000000981:diagnostic imaging*; D001706:Biopsy; D002779:Cholestasis / Q000209:etiology; D003937:Diagnosis, Differential; D005260:Female; D005704:Gallbladder / Q000002:abnormalities* / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007567:Jaundice, Neonatal / Q000209:etiology; D008297:Male; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014463:Ultrasonography