Biliary tract Normal IHDs measure less than 3 mm. Periportal lymphedema can mimic a dilated IHD but shows a low-density area completely surrounding the portal vein. A common anomaly is an aberrant IHD that drains a circumscribed portion of the liver, such as an anterior or posterior segment right lobe duct that drains into the left rather than the right main hepatic duct. The wall of the CHD and CBD can normally be demonstrated and measures less than 1.5 mm.

1. Guided by Prof Dr Dharmraj Meena.
Presented by Dr Vrishit Saraswat
II yr Resident
Department Of Radiodiagnosis

2.  Normal IHDs measure less than 3 mm.
 Periportal lymphedema can mimic a dilated
IHD but shows a low-density area completely
surrounding the portal vein.
 A common anomaly is an aberrant IHD that
drains a circumscribed portion of the liver,
such as an anterior or posterior segment right
lobe duct that drains into the left rather than
the right main hepatic duct.
 The wall of the CHD and CBD can normally be
demonstrated and measures less than 1.5 mm.

6.  Biliary Atresia – asso with polysplenia, B/L
bilobed lungs. Later -> cirrhosis, varrices,
spleenomegaly, ascites
 Abnormal Pancreaticobiliary Ductal junction
the main pancreatic duct and CBD are joined
outside the duodenal wall and form a long
common channel (usually >15 mm)
Associated with increased incidence of
cholangiocarcinoma.

7.  Choledochal Cyst – Five types. Type II is true
diverticulum of CBD
 Choledochocoele – round water density structure
found medial to pancreatic head , in C loop of
duodenum. Increased incidence with
cholangiocarcinoma.
D/d – small pseudocyst,cyctic neoplasm of pan-
head,intraluminal duodenal diverticula.
 Carolis Dx- communicating cavernous ectasia of the
IHDs. Isolated saccular dilated is uncommon -> pure
form . More common classical form – associated
with congenital hepatic fibrosis, also associated
with renal tubular ectasis and renal cystic disease.

8.  CT – may mimic multiple hepatic cyst, but
these communicate with IHD. Also may show
Central Dot sign with in dilated IHD on
contrast CT. the enhanced portion represents
the portal vein.

14.  Choledocholithiasis –
Primary and secondary stones.
Cholesterol stones ( western – accounts for 80
%)and pigment stones(asian- accounts for more
than 50%)
cholesterol stones exclusively in GB
Formation of pigment stones is related to high
prevalance of recurrent pyogenic cholangitis,
mainly by E. coli, C. sinensis, Opisthorchis viverini.

17.  Small stones easily pass into CBD and then into
duodenum.
 Stones that donot pass, reside in bile ducts and
may induce , obstructive jaundice( sometimes
fluctuative ) , cholangitis, pancreatitis.
 When stone obstruct in CBD and bile becomes
infected -> suppurative cholangitis ( chills pain
jaundice)

18.  Recurrent pyogenic cholangitis – one or two
cholangitic attck per year. -> stones continuosly
form -> pass through ampulla of vater ->
papillitis -> stricture.

19. The attenuation of stone depends on calcium
concentration

24.  Suppurative cholangitis- The presence of purulent
bile may result in increased attenuation of bile
(greater than that of water) on CT, but it is usually
not clearly depicted. Depending on the calcium
content, stones may be clearly depicted as calcified
high-attenuating foci or as noncalciied
intraluminal material.
The wall of the bile ducts may be thickened
concentrically and diffusely, with dense contrast
enhancement. In contrast to periductaliniltrating
bile duct cancer, the thickness of the bile ducts is
uniform and less than 1 mm.

25.  Recurrent Pyogenic Cholangitis- also known as
Oriental cholangitis, Oriental cholangiohepatitis, or
intrahepatic pigment stone disease.
Abdominal pain, fever, chills, and jaundice ,
when repeats once or twice a year.
The stones in patients with recurrent pyogenic
cholangitis are mainly bilirubinate pigment
stones formed in intrahepatic bile ducts.

26.  Because of repeated inflammation, the bile duct
walls are thickened diffusely owing to
inlammatory cell iniltration and fibrosis. Fibrosis
causes the bile ducts to become rigid and straight,
lacking gentle dichotomous branching.
 Larger IHDs and extrahepatic ducts become
dilated because of a stricture of the duodenal
papilla caused by mechanical irritation and
inlammation( arrow head appearance), the small
IHDs are not dilated because of ductal fibrosis.
Thus the biliary tree has a “pruned tree”
appearance,

29.  Imaging indings include stones, a dilated bile
duct, wall thickening, and duodenal papillary
stenosis.
 For patients with intrahepatic stones, the lateral
segment of the left hepatic lobe and posterior
segment of the right hepatic lobe are frequent
sites of stone lodging.

30.  In some cases, bile duct dilatation is limited to the
hepatic segmental or lobar bile ducts. This
dilatation occurs as intrahepatic stones lodge at the
branching points of large-caliber bile ducts,
causing mechanical irritation, chronic
inlammation, and ibrosis and a resultant stricture
 Frequent sites of focal stricture are the branching
points of the medial and lateral segments of the left
hepatic lobe , posterior segmental duct of the right
hepatic lobe, and bifurcation of the right and left
hepatic lobes.
 Complication – Biliary cirrhosis, intrahepatic
Cholangio Ca.

34.  Idiopathic
 Extremely Rare in asians
 M>>>F
 diffuse inflammation and fibrosis of the biliary
tree.
 lead to obliteration of the bile ducts and
subsequently biliary cirrhosis -> end stage liver dx -
> cholangiocarcinoma.
 Treatment- Liver transplant

35.  Pathology- fibrosing inlammation of the biliary tree
resulting in diffuse thickening of the bile duct wall, which if
severe enough leads to obstruction of the lumen. There is
alternating areas of focal narrowing and dilatation.
 Imaging- Cholangiogram has long been the gold standard
for the diagnosis of PSC. Multiple segmental strictures
involving the intra- and extrahepatic bile ducts are
hallmarks of the disease and characteristic findings . The
abnormality is not uniform.
When the peripheral bile ducts are obliterated, the bile ducts
have a pruned-tree appearance.
Thus the combination of short focal strictures and
dilatations, beading, pruning, and mural irregularities are
typical for PSC.

37. Extrahepatic duct stricture
(arrow)

38.  Bile Duct Hamartoma aka Von meyenburg’s
complex. On CT , appears as multiple
hypoattenuating nodules, not more than 1.5cm,
occurs throughout both lobes of liver, and does
not communicate with biliary tree. Contrast CT
shows homogenous enhancement. And
hyperintense on T2
 Bile Duct Adenoma- MC site – gall bladder,
duadenal papilla. Wedge shaped , solitary iso
to hyperattenuating mass.

42.  Biliary Papillimatosis
1. histological atypia
2. great potential for malignant transformation
3. papillomatous or villous tumor
4. either multiple or diffuse
5. Involve both extra and intrahepatic ducts
6. doesnot cause biliary obstruction, but
produces large amount of mucus, causing
nonobstructive dilatation of entire biliary tree.

45.  Biliary cystadenoma and cystadenocarcinoma
1. Cystic tumors of intrahepatic bile ducts.
2. F>>>M.
3. No communication between cystic lesion and
bile ducts.
4. Both show cystic mass with multiple
septations.
5. clear – mucinous
6. thin septa – thick septa
7. Thin walled – thick walled
8. Mural nodule absent – present
9. Capsular Calcification Absent - present

46.  In cystadenocarcinoma, the septas enhance on
contrast CT- MRI
 Cystadenoma-carcnoma of extraheaptic ducts
are very rare.
 A choledochal cyst, especially a choledochal
diverticulum or choledochocele, can be
differentiated based on the presence of septa or
a multiloculated shape. There is no
communication between the cystic tumor and
the bile duct

52.  Mass Arsie from epithelial cells of bile ducts.
 6th -7th decade.
 Hilar cholangio MC type(50-60%)
 Extra hepatic (20-30%)
 Intrahepatic ( 10-20%)
 Majority of them r adeno.
 Predisposing fac – PSC , recuurent pyogenic
cholangitis, C. sinensis. O.viverini, choledochal
cyst and caroli dx

54. PERIPHERAL INTRAHEPATIC
AND HILAR EXTRAHEPATIC
 Mass forming type
MC’ly in peripheral
intrahepatic type.
Hypovascular mass with
satellite lesions.
Doesn’t cause symptom in
early stage
 Periductal infiltrating type
mc’ly in hilar type
abnormal segment is narrowed
and proximal ducts r dilated.
Non union of left and right
duct is typical feature in hilar
type
 Intraductal type
Polypoid Mass . tubular or
papillotubular in shape.
Mucin secreting. Dilated
hepatic ducts due to
excessive secretion.
 Mass forming type.(25%)
Obstructs the lumen
completely and cause
symptoms in early stages
 Periductal infiltrating (60%)
focal or segmental concentric
thickening. Can extend in
IHD also.
Always difficult to diagnose on
CT and MR b/c of absence of
distinct tumor. Thickened
duct wall is the only finding.
Thickness of wall in
cholagitis is upto 1mm (3mm
in Ca) The lumen is also
dialated in cholangitis (
obliteration of lumen almost
completely along the whole
length of thickened segment.

55.  Intraductal (extra hepatic type)
The tumor is usually small and flat. The tumor tends to
spread supericially along the lumen for a variable
length and sometimes implants along the inner surface
of the bile ducts, resulting in multiple discrete tumors.
Although an intraductal tumor may be large,
elongated, or castlike in shape, the tumor-harboring
bile duct is typically not completely obstructed; bile
low is maintained through the space between the
tumor surface and the bile duct wall .Cholangiography
shows a serrated or velvety surface of the intraductal
tumor and a smooth normal bile duct wall. Tumor is
soft and friable and sometimes dislodge and float in
CBD, simulating a gall stone on CT.

56.  CT findings
Intra hepatic mass forming type-
Well-defined single hypovascular mass with
wavy. Owing to intrahepatic metastasis via the
portal vein, satellite or daughter nodules are
frequent.
Thick rimlike enhancement is frequently seen
around the periphery of the tumor on arterial-
phase images, and there is gradual centripetal
enhancement on delayed-phase image.

60.  CT findings
Intrahepatic Periductal infiltrating type –
On imaging, the involved bile ducts are obliterated or
diffusely narrow, whereas the bile ducts proximal to the
cholangiocarcinoma are dilated. Nonunion of the right and
left hepatic ducts with or without a visibly thickened wall
is a typical finding of an iniltrating hilar
cholangiocarcinoma
On cholangiography the lumen may be completely
obstructed or markedly narrowed. A stringlike severely
narrowed bile duct may be visualized. Hilar
cholangiocarcinoma is often associated with lobar or
segmental hepatic parenchymal atrophy, probably because
of portal vein invasion and occlusion and decreased portal
low or because of long-standing dilatation of the bile ducts
and diversion of the portal low. There are combined mass-
forming and periductal-iniltrating cholangiocarcinomas

63.  CT Findings
Intrahepatic intraductal growing type-
The bile ducts of the involved hepatic segment or lobe
are dilated.1An intraductal tumor can appear as a
polypoid mass in the lumen of the dilated bile ducts
and the walls of bile ducts r intact.
The tumor may not be seen on imaging when it is small
and isoattenuating to the adjacent hepatic parenchyma
or when the complex orientation of the dilated bile
ducts obscures the presence of the mass.
 ERCP -the involved biliary tree is dilated secondary to
partial obstruction and there are filling defects due to
the papillary tumors. There may be ine irregularities, a
velvety or serrated contour along the bile ducts,
representing the papillary surface of the tumor

65.  Extra hepatic mass forming-
Approximately 25% of extrahepatic
cholangiocarcinomas are of this type. A mass-
forming extrahepatic cholangiocarcinoma can
be easily detected on imaging because the
tumor occludes the bile duct, resulting in
dilated proximal bile ducts. Tumor mass is
small at the time of presentation. Later , tumor
may invade the wall and periductal tissue.

67.  Extrahepatic periductal infiltrating type
On CT or MRI, the thickened bile ducts can be
visualized as an enhancing ring or spot . It is often
dificult to visualize the lesion on CT or MRI because of
the absence of distinct tumor formation; these imaging
studies may show only focal or diffuse thickening of
the bile duct. At the site of bile duct obstruction, the
tumor border can be demonstrated as a symmetrically
or asymmetrically thickened bile duct wall,
constituting a transition zone.
On cholangiography or MR cholangiography, the
involved segment may not be opaciied in cases of
complete obstruction, or it may appear to be stringlike
when the lumen is not completely obstructed.

69.  Extrahepatic intraductal growing type-
On CT or MR, dialated ducts proximal to
obstruction. Degree of dilatation depends upon
Degree of obstructiion and mucin production.
Although an intraductal tumor may be large
elongated, or castlike in shape, the tumor-
harboring bile duct is typically not completely
obstructed; bile flow is maintained through the
space between the tumor surface and the bile duct
wall . Cholangiography shows a serrated or
velvety surface of the intraductal tumor and a
smooth normal bile duct wall

73.  In the preoperative assessment of an
intrahepatic cholangiocarcinoma, the primary
concern is whether an apparently tumor-free
segment of the right and left lobe is involved,
thus permitting the obviously involved
segment to be excised
 For hilar cholangiocarcinoma the preoperative
evaluation must address the extent of tumor
along the bile ducts

75.  In periductal-type hilar or extrahepatic
cholangiocarcinoma, information about the
extent of tumor along the bile ducts (including
the cystic duct), direct invasion into the
adjacent arteries and portal vein, lymph node
metastasis, and direct invasion of or metastasis
to the liver is essential

78.  CT or MRI can demonstrate thickening of the
bile ducts, but the thickening might be caused
by chronic obstruction without tumor
involvement. Therefore cholangioscopy and a
biopsy may be necessary before surgical
resection.

80.  MR cholangiography is accurate in identifying
the presence and level of a
cholangiocarcinoma. MR cholangiography in
conjunction with conventional abdominal MRI
and MR angiography yields a comprehensive
examination that permits the diagnosis and
staging of cholangiocarcinoma. An MR
cholangiogram provides information about the
extent of tumor along the bile duct, and MRI
and MR angiography provide information
about lymph node metastasis and vessel
involvement.

81. Thank you