1. General:
- Definition: Biliary atresia is a condition in which the
normal extrahepatic biliary system is disrupted.
Progressive damage of extrahepatic and intrahepatic
bile ducts secondary to inflammation may occur,
leading to fibrosis, biliary cirrhosis, and eventual liver
failure.
- Biliary atresia is characterized by luminal obstruction
of the extrahepatic bile duct with a fibrous ductal
remnant representing the obliterated duct in the porta
hepatis
- The primary therapy is surgical.

2. BILIARY ATRESIA
Prevalence: Approximately 1 in 10,000-15,000 births
Male : Female = 2/1

3. BILIARY ATRESIA
2 distinct clinical forms:
- fetal-embryonic (or syndromic): is characterized by early
cholestasis, appears in the first 2 weeks of life, accounts for
10-35% of all cases. In this form, the bile ducts are
discontinuous at birth, and 10-20% of affected neonates
have associated congenital defects: situs inversus,
polysplenia, malrotation, intestinal atresia, and cardiac
anomalies.
- perinatal (or acquired): accounts for the remaining 65-
90% cases. This form is typically found in neonates and
infants aged 2-8 weeks. Progressive inflammation and
obliteration of the extrahepatic bile ducts occurs after
birth. This form is not associated with congenital
anomalies, and infants may have a short jaundice -free
interval.

4. BILIARY ATRESIA: Classification
Classification 1:
- A(operated): 10-15%, a major
portion of the extrahepatic
bile ducts are patent (the
proximal common hepatic
duct is patent, allowing for
primary anastomosis of the
extrahepatic bile duct to the
bowel.)
- B(Inoperable): does not have
the patency shown in.

5. BILIARY ATRESIA
Kasai classification: 3 main types
- type I: the common bile duct is
obliterated while the proximal
bile ducts are patent.
- type IIa: atresia of the hepatic
duct, the cystic and common
bile ducts are patent
- type IIb: the cystic, common
bile duct, and hepatic ducts are
obliterated.
- type III: atresia refers to
discontinuity of the right and
the left hepatic ducts to the
level of the porta hepatis, more
than 90% of cases.

6. BILIARY ATRESIA
Imaging modalities:
- Ultrasonography: the initial investigation in patients
with suspected biliary atresia
- Hepatobiliary scintigraphy
- Magnetic resonance cholangiopancreatography
(MRCP)
- Surgical and percutaneous cholangiography
- Endoscopic retrograde cholangiopancreatography
( ERCP)

7. BILIARY ATRESIA
Ultrasonography:
- Technique: fasting at least 4 hours before examination.
2 times obtained: 60 -90 minutes after patient was fed.
- The gallbladder ghost triad: a gallbladder length less than
1.5cm( 1.9cm), a thin or indistinct gallbladde wall, and an
irregular and lobular contour.
- The triangular cord sign( TC sign): a circumscribed, focal,
triangular or tubular echogenic density more than 3 mm thick
located cranial to the portal vein bifurcation.
- Central biliary cysts and choledochal cysts may be associated
with biliary atresia.

8. Gallbladder contraction
- For evaluation of gallbladder contraction, the examination was
repeated 60–90 min after the infant was fed.
- The volume of the gallbladder was calculated using the following
equation: V= 0,52 x width x width x length
- Gallbladder contraction was evaluated by calculating the contraction
index (CI) as follows:
CI(%)= 100 x (fasting Volume – postprandial Volume)/ fasting Volume
- A normal CI = 86% ± 18% (mean ± SD) in 6-week-old infants(value for
patients younger than 12 weeks old) and 67% ± 42% in 4-month-old
(value for patients 12 weeks old or older )
- If the CI less than the mean ± SD, the gallbladder was described as
uncontracted.
(Sonographic Diagnosis of Biliary Atresia in Pediatric Patients Using the “Triangular Cord” Sign Versus
Gallbladder Length and Contraction)

9. Gallblader
Gallbladder ghost triad in
babies with biliary atresia.
Longitudinal scans of the
gallbladder in (A) a 3-week-
old girl and (B) a 5-week-old
boy demonstrate a short
gallbladder, an irregular or
lobulated contour, and a
relatively indistinct lining
and wall

10. 64-day-old female infant
with biliary atresia.
Sonogram shows
abnormal gallbladder
(arrows). Gallbladder is
1.0 cm long

11. Small, abnormal
gallbladder (arrow) in 8-
week-old infant with BA
has irregular wall and
abnormal shape.

12. Abnormal gallbladder
(arrow) in 10-week-old
infant with BA. Note the
more subtle irregularity
of the wall (arrowheads)
of this 21-mm-long
gallbladder.

13. TC SIGN:
a) Photograph of surgical specimen of
obliterated extrahepatic bile ducts
shows the fibrous ductal remnant
(black arrowheads) in the porta
hepatis, atretic gallbladder (arrow),
and fibrous common bile duct (white
arrowhead). The fibrous ductal
remnant is a triangular cone-shaped
mass
(b) Schematic drawing represents
the anatomic relationship between
the fibrous ductal remnant and
blood vessels around the porta
hepatis. The triangular, cone-
shaped, fibrous ductal remnant
(black arrowheads, green) is
positioned anterior and slightly
superior to the portal vein (long
arrow, blue) and the hepatic artery
(short arrow, red).

14. Triangular cord.
Transverse (a) and
longitudinal (b) scans of
the triangular cord in a
baby with biliary atresia,
which appears as a focal
echogenic triangular or
ovoid density just
cranial to the bifurcation
of the portal vein

15. 35-day-old male infant
with biliary atresia.
Sonogram reveals
tubular echogenic cord
(arrows).

16. 15-day-old female
neonate with unknown
cause of infantile
cholestasis. Sonogram
reveals tubular
echogenic cord (arrows).
“Triangular cord” was
0.3–0.4 cm wide and 1.3–
1.6 cm long.

17. Transverse sonogram
shows TC sign (arrow) in
7-week-old infant with
BA. Area of increased
echogenicity (as
indicated by calipers) is
seen anterior to
bifurcation of portal vein
(arrowheads)

18. Sonogram in 10-week-old
infant with BA shows TC sign
(arrow) superior to portal
vein (arrowhead).
The TC sign (cursors) as a
thick, tubular, echogenic area
along the anterior aspect of
the right portal vein (long
arrow)

19. (b) Transverse scan shows
triangular echogenic area
(cursors) in the anterior
aspect of the portal vein in
the porta hepatis.
Images of a 35-day-old boy
with biliary atresia. (a)
Longitudinal scan shows TC
sign (cursors) with a 5.1-mm-
thick

20. Images of a 36-day-old boy with
biliary atresia but no
demonstrable TC sign. (a)
Longitudinal US scan shows
EARPV is 3.0 mm thick between
cursors.
(b) Surgical specimen of the
fibrous ductal remnant is a
pattern of fibrous hepatic
duct (arrowheads) in the
porta hepatis.

21. Sonography sign accuracy
The diagnostic accuracy of the triangular cord
sign( TC sign) was 95%, sensitivity was 93%, and
specificity was 96%.
The diagnostic accuracy of gallbladder length was
71%, sensitivity was 72%, and specificity was 69%.
The diagnostic accuracy of gallbladder contraction
was 77%, sensitivity was 85%, and specificity was 73%.
(Sonographic Diagnosis of Biliary Atresia in Pediatric Patients Using the
“Triangular Cord” Sign Versus Gallbladder Length and Contraction)

22. Hepatobiliary scintigraphy
 A technetium-labeled iminodiacetic
acid (IDA) analogue is typically used,
include99m
Tc (technetium-99m)
DISIDA (diisopropyl-iminodiacetic
acid) and99m
Tc mebrofenin
(trimethylbromo-iminodiacetic acid).
 Infants with biliary atresia usually
have normal hepatocyte uptake of the
radiotracer if they are younger than 2
months of age.
 If excretion of radiotracer into the
bowel is seen, biliary atresia is
virtually excluded. If radiotracer
excretion is absent after 24 hours (as
it is in the image below), biliary
atresia is suspected.

23. Hepatobiliary scintigraphy
Biliary atresia in a 2-
week-old boy:
Hepatobiliary scan
obtained after a 35-
minute delay
demonstrates absence of
activity in the central
common bile duct and
small intestine

24. Surgical and percutaneous cholangiography
Surgical cholangiography is typically performed by
injecting contrast material through the gallbladder. If no
communication is seen between the biliary tree and the
gastrointestinal tract, biliary atresia is diagnosed.
Ultrasonography-guided percutaneous
cholecystocholangiography is a relatively new technique in
which radiographic contrast material is injected into the
gallbladder under ultrasonographic guidance and the
extrahepatic biliary system is viewed with fluoroscopy
Liver biopsy is often used to confirm the diagnosis of
biliary atresia and may be done at the same time as
surgical or percutaneous cholangiography

25. Surgical and percutaneous cholangiography
Biliary atresia and central
cyst:
- (A) Oblique sonogram
demonstrates a large cystic
structure in the porta
hepatis.
- (B) Intraoperative
cholangiogram
demonstrates filling of the
cyst and mildly dilated
intrahepatic ducts but no
communication with the
duodenum m

26. Liver biopsy:
Pathologic changes in
neonatal hepatitis: lobular
disarray, giant cell
transformation, and
mononuclear lobular
infiltrate.
Pathologic changes in
biliary atresia: a marked
degree of fibrosis, bile duct
proliferation, and portal
inflammation.

27. Endoscopic retrograde
cholangiopancreatography( ERCP)
ERCP allows direct visualization of the extrahepatic biliary tree
with the injection of radiologic contrast agent into the
extrahepatic biliary system through the papilla of Vater. It
requires a general anesthetic, substantial expertise, and the
availability of sufficiently small endoscopes.
This technique can show obstruction in the common bile duct
and enables visualization of the extrahepatic biliary system
distal to the common hepatic duct and the extrahepatic biliary
system with bile lakes at the porta hepatis.
ERCP, while not an alternative to noninvasive imaging, can be
used to avoid surgery in approximately 25% of cases
(a study by Petersen et al)

28. Magnetic Resonance Cholangiography
MRCP is a relatively new technique for neonatal
imaging.
Findings in infants with biliary atresia include
incomplete visualization of the extrahepatic biliary
system and periportal high signal intensity on T2-
weighted magnetic resonance imaging (MRI) scans
(which may represent cystic dilatation of fetal bile
ducts with surrounding fibrosis).

29. Triangular Area of High Signal Intensity in the Porta Hepatis at
T2-weighted MR Cholangiography with US Correlation
Images obtained in a 13-day-old
female neonate with acholic stool. (a)
Transverse gray-scale US image of the
liver shows an echogenic triangular
cord (arrowheads) that contains a
linear hypoechoic lesion (arrow).
Oblique coronal thick-slab T2-
weighted single-shot fast SE MR
cholangiogram shows a triangular
area of high signal intensity (arrow) in
the porta hepatis and does not show
the extrahepatic bile duct.

30. a 57-day-old female infant with
cholestatic jaundice and acholic stool.
power Doppler US image shows a
tubular cystic lesion (straight arrow),
which does not have a flow signal,
anterior to the portal vein (curved
arrow). Cursors indicate the
maximum depth of this cystic lesion
Oblique coronal T2-weighted
single-shot fast SE MR
cholangiogram demonstrates an
inverted triangular area of high
signal intensity (arrow) and a
normal gallbladder (arrowheads).

31. in a 59-day-old female infant with
persistent jaundice and acholic
stool. (a) Transverse power
Doppler US image of the liver
shows a small ovoid hypoechoic
lesion (arrow) within a triangular
cord that abuts the portal vein.
Oblique coronal thick-slab T2-
weighted single-shot fast SE
MR cholangiogram shows a
small triangular area of high
signal intensity (arrow) in the
porta hepatis

32. Images obtained in a 40-day-old
female infant with jaundice and
acholic stool. (a) Oblique gray-scale
US image of the liver shows a
triangular hypoechoic lesion (long
straight arrow) within a periportal
echogenic mass, a dilated common
bile duct (short straight arrow), and
the portal vein (curved arrow).
Cursors indicate the maximum width
(0.79 cm) of the dilated common bile
duct.
(b) Oblique coronal thick-slab MR T2-
weighted single-shot fast SE MR
cholangiogram shows a choledochal
cyst (short arrow) and the gallbladder
(arrowheads). The triangular area of
high signal intensity (long arrow)
located in the porta hepatis is not
continuous with the choledochal cyst
or gallbladder. Intraoperative
cholangiogram (not shown)
demonstrated a choledochal cyst, but
the triangular structure at the porta
hepatis was not visualized.

33. BILIARY ATRESIA
Treatment: Kasai portoenterostomy( a Roux-en-Y
anastomosis of the bowel to the bed of the porta
hepatis)
Prognostic: patient had BA will have good prognosis
if be operated as soon as possible before 3 months of
age
Final stage: biliary cirrhosis must be undergone liver
transplatation.