Biliary atresia: making the diagnosis by the gallbladder ghost triad.
OBJECTIVE
To describe the gallbladder ghost triad and evaluate its usefulness in the sonographic diagnosis of extrahepatic biliary atresia (BA).


METHODS
From October 1997 to February 2002, 217 fasted infants with cholestatic jaundice aged 2-12 weeks were examined sonographically. We defined the gallbladder ghost triad as gallbladder length <1.9 cm, lack of smooth/complete echogenic mucosal lining with an indistinct wall and irregular/lobular contour, and used it as a criteria for BA. Gallbladder wall thickness, triangular cord, diffuse periportal echogenicity and hepatic artery calibre were also recorded. Diagnosis of BA was confirmed surgically and histologically.


RESULTS
Thirty of 31 babies with BA demonstrated the gallbladder ghost triad. No false-positives were recorded. The 31st BA baby showed a normal gallbladder at 6 weeks, but developed the ghost triad at 8 weeks. Gallbladder wall thickening was seen in 46/186 non-BA babies, but not in BA. Triangular cord was observed in 24/31 babies. Twenty-two of 186 non-BA babies and 5/31 BA babies showed diffuse periportal echogenicity. The hepatic artery appeared more prominent in BA. All 31 babies diagnosed sonographically as BA had surgery. Three non-BA babies had "negative" laparotomies showing hypoplastic bile ducts.


CONCLUSIONS
The gallbladder ghost triad is a very accurate sign of BA. Indeterminate cases require close follow-up.
Tan Kendrick
Anne Poh Ann
AP
Department of Diagnostic Imaging, Kandang Kerbau Women's and Children's Hospital, 100 Bukit Timah Road, 229899, Singapore. annetan@kkh.com.sg
Phua
Kong Boo
KB
Ooi
Boo Chye
BC
Tan
Carolyn Eng Looi
CE
D017734:Bile Ducts, Extrahepatic / Q000002:abnormalities* / Q000000981:diagnostic imaging; D001656:Biliary Atresia / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D002779:Cholestasis / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005500:Follow-Up Studies; D005704:Gallbladder / Q000002:abnormalities* / Q000000981:diagnostic imaging; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007567:Jaundice, Neonatal / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D014463:Ultrasonography