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331
Case
Thickened
Bile Duct Wall Simulating
Ductal
Report
Dilatation
on
Sonography D. Middleton1
William
Sonography
and A. Stephen
is an accurate
Surratt
noninvasive
method
nodal
of meas-
the caliber of the bile ducts. Inaccuracies in ductal measurements generally result when other structures, such uring
as hepatic
arteries,
tortuous
gallbladder necks, or cystic [1 , 2]. We have recently en-
ducts, simulate the bile ducts countered a case of diffuse thickening of the duct wall that simulated a dilated duct despite correct identification of the duct
itself.
This report
describes
this potential
pitfall
obliterated luminal reflection sign that ultimately correct diagnosis to be made.
allowed
the
man with a history
of cholecystectomy
hepatis
showed
anterior
to the right hepatic
the
hepatic
common
duct
hepatic
duct
artery
in its
expected
location
(Fig. 1A). The diameter
was measured
as 9-1 0 mm. Subtle
of the low-level
echoes in the duct were interpreted as artifactual. Biliary obstruction was diagnosed, and the level of obstruction was determined to be the mid to distal portion of the common bile duct. Because the distal of the
common
was
not
bile duct
determined,
for further sonograms reflection
was and
not
the
visualized,
patient
a cause
was
brought
of the biliary tract. These showed
in the center
of the common
hepatic
duct
of
back
a thin linear
(Fig. 1 B), which
was thought to represent the interface between the coapted luminal surfaces of a duct with marked diffuse hypoechoic wall thickening and an obliterated Received I
lumen.
February
Both authors:
obtained
intrahepatic
ducts
(Fig.
1C).
ducts
with
Results
of
the next
day
bile duct, common dilatation brush
biopsy
showed
hepatic
of the peripheral were
positive
Discussion When biliary obstruction is detected sonographically in the jaundiced patient, the next objective is to determine the level and cause of obstruction. The reported sensitivities of sonog-
4, 1992;
Mallinckrodt
The diagnosis accepted Institute
of cholangiocarcinoma
after revision of Radiology,
March
with
August 1992 0361 -803X/92/1592-0331
lumen
and the thickened
of the duct
hypoechoic
was
not identified
initially,
walls of the duct were inter-
preted as the lumen. This resulted in the erroneous impression of dilatation ofthe common hepatic duct and the inappropriate conclusion that the level of obstruction was in the mid to
distal portion of the common bile duct. Ultimately, the obliterated lumen of the bile duct was identified as a thin linear reflection in the middle of the duct, and this made it possible to recognize that the duct wall was markedly thickened. This then led to the correct determination of the level of obstruction. Although a number of processes such as sclerosing cholangitis, AIDS cholangiopathy, choledocholithiasis, oriental cholangiohepatitis, and pancreatitis could have produced the thickening of the duct’s wall [51, the magnitude of thickening (5 mm) and the associated bulky adenopathy strongly favored cholangiocarcinoma.
5, 1992.
Washington
University
School
of Medicine,
requests to W. D. Middleton. AJR 159:331-332,
An ERCP
for cholangiocarcinoma.
the obliterated
had painless
jaundice and was referred for sonography of the right upper quadrant. Views of the liver showed moderate dilatation of the intrahepatic ducts and bulky periportal lymphadenopathy. Views of the porta
obstruction
and central
intrahepatic
made.
raphy in determining the level and the cause of obstruction are 92-95% and 71-88%, respectively [3, 4]. In this case,
An 84-year-old
portion
duct,
was
irregular lumen of the common
and the
Case Report
common
metastases
a narrowed
© American
Roentgen
Ray Society
51 0 S. Kingshighway
Blvd.,
St. Louis,
MO 631 10. Address
reprint
MIDDLETON
Downloaded from www.ajronline.org by 120.32.95.59 on 10/10/15 from IP address 120.32.95.59. Copyright ARRS. For personal use only; all rights reserved
332
AND
SURRATT
AJR:159,
Fig. 1.-A, Initial sonogram shows thickening of wall of common hepatic duct (d), simulating ductal portal vein, n = enlarged node. B, Second sonogram of common hepatic duct shows obliterated luminal reflection sign (arrows). C, ERCP shows diffuse narrowing of extrahepatic and central intrahepatic ducts (arrows) with dilated
dilatation.
Arrow
peripheral
=
right
intrahepatic
hepatic
August
artery,
v
1992
=
right
ducts.
has recently been described in renal transplants with thickened urothelium [7]. In their description of the “white line sign,” useful
Cunningham and Bacani-Faulls this sign is in detecting subtle
[7] have stressed how thickening of the renal
collecting system and distinguishing it from mild hydronephrosis. These points are equally important in the bile duct. Unlike the bile duct, the obliterated renal collecting system produces flat, two-dimensional interfaces, and therefore, this finding can be expected to be seen more frequently in the
kidney than in the biliary tract. In summary,
appearance marked
sonogram sign (arrows)
of pancreatic in distal
of common
concentric
thickening
interpretation
of the obliterated
help to avoid
potential
diagnosis
sonographic
lumen
of the ductal
sign
should
the
wall.
due to
Detection
luminal reflection
inaccuracies
in the sono-
of the level and cause of biliary obstruction.
REFERENCES
patients
with
a thickened
pletely obliterated lumen is uncommon. is completely compressed, we expect
produce the obliterated luminal reflecting interface is essentially less, we have langiocarcinoma
extrahepatic
bile duct,
Even when the lumen it will be difficult to
reflection sign because the one dimensional. Neverthe-
since encountered a second patient with choin whom the sign was present in the distal
of the common
A finding
illustrate
bile duct
the lumen remains patent. This makes it possible to define the luminal surfaces as two bright linear reflections separated by the intraluminal bile. The thickened wall is then seen as a hypoechoic layer deep to the mucosal surface [6]. A com-
portion
cases
head (P) shows oblitera-
portion
(arrowheads).
In most
two
and proper graphic Fig. 2.-Longitudinal ted luminal reflection
these
of a bile duct with an obliterated
similar
bile duct (Fig. 2).
to the obliterated
luminal
reflection
sign
1 . Callen PW, CA, Callen Saunders, 2. Parulekar
Mahoney BS. Gallbladder and bile ducts. In: Vogler JB, Helms PW, eds. Normal variants and pitfalls in imaging. Philadelphia: 1986:288-297 SG, Sonography of the distal cystic duct. J Ultrasound Med
1989;8:367-373 3. Laing FC, Jeffrey RB, Wing VW, Nyberg DA. Biliary dilatation: level and cause by real-time US. Radiology 1986;160:39-42 4. Gibson RN, Yeung E, Thompson JN, et al. Bile duct obstruction: evaluation of level, cause and tumor resectability. Radiology 43-47 5. Schulte Si, Baron AL, Teefey SA, et al. CT of the extrahepatic
wall thickness
and contrast
enhancement
defining
the
radiologic 1986;1 60: bile ducts:
in normal and abnormal ducts.
AJR 1990;154:79-85 6. Carroll BA, Oppenheimer DA. Sclerosing cholangitis: sonographic demonstration of bile duct wall thickening. AiR 1982;1 39:1016-1018 7. Cunningham JJ, Bacani-Faulls M. Sonographic “white line sign” for detection of minimal mucosal thickening in renal transplants. Urology
1990;35:367-370
331
Case
Thickened
Bile Duct Wall Simulating
Ductal
Report
Dilatation
on
Sonography D. Middleton1
William
Sonography
and A. Stephen
is an accurate
Surratt
noninvasive
method
nodal
of meas-
the caliber of the bile ducts. Inaccuracies in ductal measurements generally result when other structures, such uring
as hepatic
arteries,
tortuous
gallbladder necks, or cystic [1 , 2]. We have recently en-
ducts, simulate the bile ducts countered a case of diffuse thickening of the duct wall that simulated a dilated duct despite correct identification of the duct
itself.
This report
describes
this potential
pitfall
obliterated luminal reflection sign that ultimately correct diagnosis to be made.
allowed
the
man with a history
of cholecystectomy
hepatis
showed
anterior
to the right hepatic
the
hepatic
common
duct
hepatic
duct
artery
in its
expected
location
(Fig. 1A). The diameter
was measured
as 9-1 0 mm. Subtle
of the low-level
echoes in the duct were interpreted as artifactual. Biliary obstruction was diagnosed, and the level of obstruction was determined to be the mid to distal portion of the common bile duct. Because the distal of the
common
was
not
bile duct
determined,
for further sonograms reflection
was and
not
the
visualized,
patient
a cause
was
brought
of the biliary tract. These showed
in the center
of the common
hepatic
duct
of
back
a thin linear
(Fig. 1 B), which
was thought to represent the interface between the coapted luminal surfaces of a duct with marked diffuse hypoechoic wall thickening and an obliterated Received I
lumen.
February
Both authors:
obtained
intrahepatic
ducts
(Fig.
1C).
ducts
with
Results
of
the next
day
bile duct, common dilatation brush
biopsy
showed
hepatic
of the peripheral were
positive
Discussion When biliary obstruction is detected sonographically in the jaundiced patient, the next objective is to determine the level and cause of obstruction. The reported sensitivities of sonog-
4, 1992;
Mallinckrodt
The diagnosis accepted Institute
of cholangiocarcinoma
after revision of Radiology,
March
with
August 1992 0361 -803X/92/1592-0331
lumen
and the thickened
of the duct
hypoechoic
was
not identified
initially,
walls of the duct were inter-
preted as the lumen. This resulted in the erroneous impression of dilatation ofthe common hepatic duct and the inappropriate conclusion that the level of obstruction was in the mid to
distal portion of the common bile duct. Ultimately, the obliterated lumen of the bile duct was identified as a thin linear reflection in the middle of the duct, and this made it possible to recognize that the duct wall was markedly thickened. This then led to the correct determination of the level of obstruction. Although a number of processes such as sclerosing cholangitis, AIDS cholangiopathy, choledocholithiasis, oriental cholangiohepatitis, and pancreatitis could have produced the thickening of the duct’s wall [51, the magnitude of thickening (5 mm) and the associated bulky adenopathy strongly favored cholangiocarcinoma.
5, 1992.
Washington
University
School
of Medicine,
requests to W. D. Middleton. AJR 159:331-332,
An ERCP
for cholangiocarcinoma.
the obliterated
had painless
jaundice and was referred for sonography of the right upper quadrant. Views of the liver showed moderate dilatation of the intrahepatic ducts and bulky periportal lymphadenopathy. Views of the porta
obstruction
and central
intrahepatic
made.
raphy in determining the level and the cause of obstruction are 92-95% and 71-88%, respectively [3, 4]. In this case,
An 84-year-old
portion
duct,
was
irregular lumen of the common
and the
Case Report
common
metastases
a narrowed
© American
Roentgen
Ray Society
51 0 S. Kingshighway
Blvd.,
St. Louis,
MO 631 10. Address
reprint
MIDDLETON
Downloaded from www.ajronline.org by 120.32.95.59 on 10/10/15 from IP address 120.32.95.59. Copyright ARRS. For personal use only; all rights reserved
332
AND
SURRATT
AJR:159,
Fig. 1.-A, Initial sonogram shows thickening of wall of common hepatic duct (d), simulating ductal portal vein, n = enlarged node. B, Second sonogram of common hepatic duct shows obliterated luminal reflection sign (arrows). C, ERCP shows diffuse narrowing of extrahepatic and central intrahepatic ducts (arrows) with dilated
dilatation.
Arrow
peripheral
=
right
intrahepatic
hepatic
August
artery,
v
1992
=
right
ducts.
has recently been described in renal transplants with thickened urothelium [7]. In their description of the “white line sign,” useful
Cunningham and Bacani-Faulls this sign is in detecting subtle
[7] have stressed how thickening of the renal
collecting system and distinguishing it from mild hydronephrosis. These points are equally important in the bile duct. Unlike the bile duct, the obliterated renal collecting system produces flat, two-dimensional interfaces, and therefore, this finding can be expected to be seen more frequently in the
kidney than in the biliary tract. In summary,
appearance marked
sonogram sign (arrows)
of pancreatic in distal
of common
concentric
thickening
interpretation
of the obliterated
help to avoid
potential
diagnosis
sonographic
lumen
of the ductal
sign
should
the
wall.
due to
Detection
luminal reflection
inaccuracies
in the sono-
of the level and cause of biliary obstruction.
REFERENCES
patients
with
a thickened
pletely obliterated lumen is uncommon. is completely compressed, we expect
produce the obliterated luminal reflecting interface is essentially less, we have langiocarcinoma
extrahepatic
bile duct,
Even when the lumen it will be difficult to
reflection sign because the one dimensional. Neverthe-
since encountered a second patient with choin whom the sign was present in the distal
of the common
A finding
illustrate
bile duct
the lumen remains patent. This makes it possible to define the luminal surfaces as two bright linear reflections separated by the intraluminal bile. The thickened wall is then seen as a hypoechoic layer deep to the mucosal surface [6]. A com-
portion
cases
head (P) shows oblitera-
portion
(arrowheads).
In most
two
and proper graphic Fig. 2.-Longitudinal ted luminal reflection
these
of a bile duct with an obliterated
similar
bile duct (Fig. 2).
to the obliterated
luminal
reflection
sign
1 . Callen PW, CA, Callen Saunders, 2. Parulekar
Mahoney BS. Gallbladder and bile ducts. In: Vogler JB, Helms PW, eds. Normal variants and pitfalls in imaging. Philadelphia: 1986:288-297 SG, Sonography of the distal cystic duct. J Ultrasound Med
1989;8:367-373 3. Laing FC, Jeffrey RB, Wing VW, Nyberg DA. Biliary dilatation: level and cause by real-time US. Radiology 1986;160:39-42 4. Gibson RN, Yeung E, Thompson JN, et al. Bile duct obstruction: evaluation of level, cause and tumor resectability. Radiology 43-47 5. Schulte Si, Baron AL, Teefey SA, et al. CT of the extrahepatic
wall thickness
and contrast
enhancement
defining
the
radiologic 1986;1 60: bile ducts:
in normal and abnormal ducts.
AJR 1990;154:79-85 6. Carroll BA, Oppenheimer DA. Sclerosing cholangitis: sonographic demonstration of bile duct wall thickening. AiR 1982;1 39:1016-1018 7. Cunningham JJ, Bacani-Faulls M. Sonographic “white line sign” for detection of minimal mucosal thickening in renal transplants. Urology
1990;35:367-370
