Pitfalls and Differential Diagnosis in Biliary Sonography1 StantonJ. Rosenthal, MD Glendon G. Cox, MD Louis H. Wetzel, MD Solomon Batnitzky, MD

Ultrasonography Most

has

cases

are

manifestations, agnostic the

uncommon challenges.

following

factive

sludge,

Issues air,

and

hepatitis,

and

vs ascites,

bus

portal

and

obstruction

ulcer,

biliary

atresia,

discussed

for

vs tume-

(acute

ascites,

cholecys-

hypoalbuminemia,

, pericholecystic and trauma) , bile cholangitis,

fluid

and

disease,

and

(chole-

duct

biliary

disease,

biliary

di-

cholecystosis,

thickening

Caroli

neonatal

present

(calculi

infestation,

vs sclerosing

may

are

echoes

artifacts,

disease. unusual

that

diagnosis

wall

cholangitis)

and

artifacts

parasitic

perforated

of biliary emphasize

gallbladder

, gallbladder

scierosing

perinatal

imaging

authors

in differential

hematobilia,

system,

cinoma),

the

cholecystitis,

cystitis

(biliary

in the

but

internal

artifacts)

vs acalculous

tion

role diseases,

findings:

neop!asia,

titis

a primary

straightforward,

dilataair,

anoma-

cholangiocarsclerosing

chol-

angitis. U INTRODUCTION Investigation of disease of the bibiary tract and liver has been an important focus of scientific inquiry from ancient times to the present. Babylonian priests practicing divination studied hepatobiliary pathologic specimens from sacrificial sheep for important clues to the future. Clay models of sheep livers and gabbbladders produced over 4,000 years ago (Fig 1) are highly accurate and detailed depictions of hepatobiliary anatomy and represent some of the earliest known anatomic studies. As imaging techniques have improved, diagnostic radiologists have increasingly studied images of the bibiat-y tract. Plain radiography, oral cholecystography, intravenous cholangiognaphy, ultnasonography (US) , computed tomography (CT) , percutaneous cholangiography, endoscopic retrograde pancreaticocholangiography

Abbreviations:

AIDS

acquired

immunodelicienc)

syndrome.

RAO

right

anterior

oblique,

WES

wall,

echo,

shadow. Index enlarged. 76.

terms: 76.28

1 298

I

From

1990;

the

Department

City,

questedjune C

RSNA,

ducts. abnormalities, ducts, neoplasms,

76.

#{149} Bile

#{149} Cholangitis,

RadioGraphics

Kansas

Bile

KS 66103. 2 1 ; revision

76.288

76.3

#{149} Cholecystitis.

14

#{149} Bile

#{149} Bile

ducts, calculi, ducts, stenosis

76.28 #{149} Bile or obstruction,

ducts, 76.28

diseases, #{149} Bile

76.28 #{149} Bile ducts, ducts, US studies,

76.285

10:28-311 of Diagnostic From

the

received

Radiology. 1988

RSNA

September

University annual

meeting.

1 1 . Address

of Kansas Received reprint

Medical April requests

Center, F7,

1989;

Rainbow accepted

Boulevard and

at 39th revision

St.

re

to SiR.

1990

285

(ERCP) , and magnetic resonance (MR) irnaging all have been or are used in evaluation of biliary tract disease. Of these, sonography is most often employed as the primary imaging tool because it has high sensitivity for the presence of gallstones, it enables accurate evaluation of the status of the intraand cxtrahepatic biliary ducts, and the examination can be performed relatively rapidly and at bow cost (1-3). In most cases, the US evabualion

is straightforward,

aging

pitfalls

complicate

U

occasionally

irn-

presentations

the sonographic

These potential this article.

The

but

or unusual

may

evaluation.

problems

form

the

CHOLELITHIASIS US diagnosis of cholebithiasis

basis

of

Figure 1. Babylonian and gallbladder (circa

is usually

one of the most straightforward in medical imaging. High-amplitude echoes within the lumen of the gallbladder that produce

“clean,” that

sharply

move

defined,

with

change

are virtually always of clean shadowing sus

“dirty”

echoes

fined

the

margins,

model Bc)

of sheep

liver with

. (Reprinted,

permission.)

shadows position

gallstones. produced

shadowing

within

anechoic in patient

clay 2000

The concept by calculi yen-

(multiple

shadowed

internal

area,

or a curtainbike

poorly

effect)

de-

has

been used to differentiate calculi from gas in bowel loops adjacent to the gallbladder, particularby the first portion of the duodenum.

Although in many

this cases,

reflection

quency even

culi

of the

and

sound

point is useful of absorption and increases

may vary

from

the

patient.

within

may

differentiating the degree

produce

same

both

clean

with

stone

fre-

to stone,

As a result,

and dirty

cal-

shad-

owing (Fig 2) . Variations in the angle of mcidence between the ultrasound beam and the calculi may also contribute to these differences (1 ,3). Occasionally, intense reverberations within stones produce typical dirty shadows and may closely mimic the effect of

duodenab

gas compressing

the gallbladder

(Fig 3) . In interpreting a case of this sort, careful real-time observation of the movement of the stone with change in patient position will result in a correct diagnosis (Figs 4 , 5). Examination of the gallbladder with the patient in prone, decubitus, and upright

286

U

RadioGrapbics

U

Rosenthal

et a!

Figure

2.

Sonogram

cholelithiasis demonstrates culi that produce clean

head)

of a straightforward four (arrow)

case

well-defined and dirty

of

cal. (arrow-

shadowing.

positions is critically important to minimize false-negative diagnoses (Fig 6). If the patient has not fasted, the gallbladden may appear contracted or absent on sonograms. Bright, irregular echoes in the gallbladder fossa associated with an intense, usually clean shadow indicate the presence of multiple calculi in a contracted gallbladder (Fig 7) . This appearance can be closely mirn-

Volume

10

Number

2

.

#

-

.

#{149}.‘

.w

-.----

a.

b.

Figure 3. (a) Sonogram of gallbladder calculus (arrows) nal gas compressing the gallbladder. (b) Oral cholecystogram transparent crystalline stone (arrows).

4a.

demonstrates reveals

true

dirty shadows that mimic duodenature of the single, large,

4b. Figures 4, 5. (4a) Sonogram shows hypenechoic foci strongly resembling gallstones that were caused by an irregular impression of duodenal gas (arrow)

on the

posterior

aspect

den. (4b) Another sonognam later after a peristaltic wave

-:7-,. .

bladder. #{149}

4c:

.-

Sonogram

gallblad-

of another

case

demon-

.-

. .#“a V

(5)

of the

obtained moments shows a normal gall-

ference

>

.

strates

.

,

gas

(arrow)

mimicking

in size between

a gallstone.

the large

The

shadow

dif-

and the

smaller hyperechoic reflector (arrow) and the inconstancy of these findings during real-time scanfling indicate the source of the echoes is not a calculus.

,

;

.

5.

March

1990

Rosenthal

et a!

U

RadioGrapbics

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287

a.

b.

Figure 6. (b) Another

(a) Sonogram obtained sonogram taken with

with the patient the same patient

supine standing

‘

reveals clearly

.

-I

-.

an apparently normal gallbladder. shows multiple calculi.

.

.. .‘a.:

-.

.-

.1

. :

.. :

#{149}:

-

.

: .

.

-.‘--

#{149}

-..-..

-

.

4

. -

I: .±-

8.

7.

WES (wall, echo, shadow) triad (arrows)-a specific sign for a contracted, stone-filled gallbladder. The WES sign is composed of two parallel echogenic arcs produced by the leading edge of the gallbladder wall and the stones. Bile creates a thin, echopenic zone between the arcs, and the stones produce a posterior shadow (4) . (8) Sonogram demonstrates a hyperechoic structure with a shadow, but the WES triad is not present. In this case, gas in the bowel occupying the gallbladder fossa mimicked the appearance of gallstones. Figures

288

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Ra4ioGrapbics

7, 8.

(7)

U

Sonogram

Rosenthal

demonstrates

et a!

the

Volume

10

Number

2

res

9, 10. (9) tnnow) projecting

ILongitudinal

Sonogram demonstrates into the gallbladder (a)

and

transverse

(b)

pollumen. scans

ob-

I in another case reveal a round artifact (ancaused by dust within a multiformat camera tlosely mimics

icked

by gas-containing

bowel

in the gall-

bladder fossa if the gallbladder is contracted due to a recent fatty meal (Fig 8) . The dirty shadow seen in Figure 8 is helpful but not infallible evidence that gallstones are not present. Observing the passage of water through the duodenum on noting a WES triad may clarify this situation. U

NONCALCULUS

bibiary

March

sludge,

1990

festation, gallbladder empyerna, ma. Gallbladder polyps, either papilbornas, are nonshadowing, soft-tissue

masses

projecting

and carcinoadenomas or nonrnobibe into

They are usually less than 1 cm (1 -3) (Fig 9) . We encountered which a camera artifact mimicked pearance of a polyp (Fig 10).

the

lumen.

in diameter

a case

in

the

ap-

STRUCTURES

WITHIN THE GALLBLADDER Many entities other than calculi echoes within the gallbladder, enomatous polyps, hyperplastic sis,

a polyp.

hematobilia,

produce including cholecystoparasitic

adin-

Rosenthal

et a!

U

RadioGrapbics

U

289

_v..

‘

..

-

‘

,,V#{149}:..

Frb%..,

13. Figures sludge ceiving

11-14.

Sonognams

(arrows in 13) hyperalimentation

,

and

demonstrate

biliary

290

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tients

undergoing

cases, with

RadioGrapbics

U

Rosenthal

appear

similar

of pus

that

(12)

sludge

filling

shows

hyperalimentation.

the entire sludge (3)

14. (arrows

collections

Gallbladder sludge is viscous bile, usually with a high bilirubin content, that is frequently seen in cases of biliary stasis (Fig 1 1) . This may be a normal finding accompaflying prolonged fasting, particularly in pathese filled

sludge

gallbladder (Fig 1 2).

et a!

In

may

be

the entire

in 11), to sludge

.

.

.;.

partial

r..

volume

(14).

artifact

Sonogram

resembling

of a patient

re-

gallbladder.

Artifact from partial produce an appearance (Fig 13), but in general,

volume averaging resembling sludge the echogenicity

may

within the gallbladder decreases with increasing distance from the adjacent bright reflector that contributes to the artifact. Pathologic biliary stasis, such as that accompanying acalcubous cholecystitis, produces collections of pus or dense bile that are simibar to sludge found in fasting patients (5) (Fig 1 4) . Milk-of-calcium bile may also re-

Volume

10

Number

2

a. Figure

15.

Sonognam

milk-of-calcium

bile

(a) that

and CT scans resembles

b. obtained

(b)

sludge

(arrows)

in a case (cf Fig

of cholelithiasis

semble calcium genic

ed with

sludge (Fig 1 5) However, bile is usually somewhat .

-

than

sludge

and

calculi

and

is frequently

cholecystitis.

associat-

Tumefac-

echogenic

March

patients (3). can result in accumulation

material

1990

within

the

. - 7. Sonogram sludgebike material

(GB)

;

however,

suggestive

tive sludge is also commonly associated with cholelithiasis (Fig 1 6) and has been observed to evolve into calcium bilirubinate

stones in many Hematobilia

veals

of a case within

‘#{149}

milk-ofmore echo-

show

that

may

T

T:

.m

Figure 16. Sonogram demonstrates tumefactive sludge (arrows) , associated with both gallstones and thickening of the gallbladder wall secondary to acute cholecystitis.

and cholecystitis

1 1).

the septations

of the

true

simulate

of hematobilia the gallbladder

in the mass

are

diagnosis.

the

sonographic

ance of sludge on pus. idence of organization

appear-

Septations or other cvwithin the gallbladder

and the presence of dilated bile ducts, which are frequently associated with hematobibia,

are findings thai

condition

suggestive (Fig

of this

potentially

be-

17).

of

gallbladder

Rosenthal

et a!

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Ra4ioGrapbics

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291

a. b. Figure 18. Sonogram (a) shows phrygian cap configuration. This radiologic finding was so named because of its similarity to the “cap of liberty” bestowed on freed slaves in ancient Phrygia (b). The appearance is produced by a sharp fold in the lower portion of the gallbladder, which causes the fundus (arrows in a)

U

to lie anterior

to the

GALLBLADDER

body

of the

gallbladder.

VARIATIONS

There are many variations gallbladder, most of which

This

in the shape of the are only anatomic

curiosities. One of the best known is the phrygian cap (Fig 1 8), which is produced by a sharp fold in the lower portion of the gallbladder. This configuration has no clinical significance. A more common fold occurs in the proximal portion of the gallbladder, resulting

in a sharp

angubation

of the

gablbbad-

den body on its neck. This variation is usually best seen in longitudinal scans (Fig 1 9a). The same fold in a transverse view often has the false appearance of a septum (Fig 1 9b).

292

U

RadioGraphics

U

Rosenthal

et a!

appearance

must

also

be

differentiated

from that caused by a layer of small calculi suspended between bile of differing viscosities (Fig 20) . The floating calculi can be connectby diagnosed by noting that the layer nemains horizontal, despite changes in patient position. True septations do occur within the gallbladder (Fig 2 1), but they are seldom associated with symptoms. Variations in the shape and position of the gallbladder may become clinically significant when they act to obscure diagnostic information. Figure 22 is an axial scan of a transversely oriented gallbladder in a patient with acute chobecystitis. Wall thickening was

noted

in many

could

be identified

scans,

but only

the large in transverse

Volume

10

calculus views.

Number

2

Figures

19-21. (19a) Longitudinal US scan shows fold (arrow) in proximal scan of the same case, the fold could be confused with a septum of the gallbladder. (20) Sonogram of another case reveals layer of suspended transverse

similar

to the

proximal

fold.

Compare

these

images

with

that

Figure calculus

of actual

22.

March

1990

Transverse

(arrow)

bladder that en planes.

septa

was

gallbladder

(arrow) calculi in the

gallbladder

sonogram

(19b) On aspect appears

(21).

reveals

obstructing the missed on scans

Rosenthal

(GB).

in the posterior (arrows) that

large

neck of the gallobtained in oth-

et a!

U

Ra4ioGrapbics

U

293

23.

24.

Figures 23-25. (23) Sonogram shows thickening of the gallbladder wall (arrows) caused by acute cholecystitis induced by a single calculus (arrowhead) impacted in the neck of the gallbladden. (24) Gallbladder wall thickening seen on this sonogram of a patient with ascites is at least in part an artifact caused by the presence of closely apposed strong reflecting surfaces at the ascitesgallbladder wall interface and the immediately adjacent

(25)

gallbladder

Sonogram

wall (arrows), and alcoholic halo

wall-bile

shows produced hepatitis,

in a chronic

interface

a thickened

alcoholic

(arrows).

gallbladder

by hypoalbuminemia and a penicholecystic without

ascites.

U GALLBLADDER WALL THICKENING Evaluation of gallbladder wall thickness plays an important role in the sonographic study of the biliary system. The gallbladder wall is no more than 2 mm thick in 97% of healthy subjects, provided that the short axis of the gallbladder is at beast 2 cm in diameten. Acute cholecystitis is a major cause of wall thickening (Fig 23) and is the most likeby diagnosis if the wall thickness exceeds 5 mm. The confident US diagnosis of chobecystitis is based on the criteria of wail thickness of greater than 4 mm and a round or oval gallbladder distended to a transverse diameten of at least 5 cm. Other important criteria are gallbladder wall lucency or “halo” and

294

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et a!

cholelithiasis. becystitis

tics.

Many will

not

patients

have

Nevertheless,

all

the

duced

by the presence

id, hypoalbuminernia, une, and incomplete In addition, focal bladder carcinoma (1-3,6).

acute

cho-

charactenis-

diagnosis

pected due to the presence moderate wail thickening, ness. In these cases, duct obstruction by scintigraphy is often Other important thickening include

with these

can

be sus-

of gallstones, and focal tender-

confirmation of cystic means of hepatobiliary useful (3). causes of gallbladder wall hepatitis, artifacts in-

of penicholecystic

flu-

right-sided heart failgallbladder distention. thickening occurs in galland adenornyornatosis

Volume

10

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2

of findings in patients with viral pericholecystitis. Findings resemble those of acalcubus chobecystitis, except that the gallblad-

den tends to be contracted The degree of contraction cases with the most and penicholecystic

the wall

rather than dilated. is greatest in those

marked wall organization.

thickening,

internal

thickening Despite

gallbladder

echoes

were absent in all cases. All of our patients with viral penicholecystitis were under 35 years of age, and none had a history of recent surgery, trauma, or burns. All presented with right upper quadrant pain and tenderness. Hepatobiliary scintigraphy demonstratT

‘

ed patency

1

Gallbladder

..

tx.,

-‘-

Figure 27. Sonogram shows thickened den wall in a patient with AIDS.

ease

March

may also

1990

gallblad-

wall thickening in the presis primarily artifactual. and chronic liver dis-

contribute

to this

wall

duct

thickening

in all cases. has

also

been

observed deficiency

:-

Gallbladder ence of ascites Hypoalbuminernia

of the cystic

in patients with acquired immunosyndrome (AIDS) (Fig 27) . Grurnbach et al (7) reported gallbladder wall thickening in 55% of 22 patients with AIDS. There was an increased prevalence of extrabiliary cytomegabovirus final cryptosponidiosis as in other AIDS patients ducts (7).

infestation and intesin this group as well with dilated bile

appearance

Rosenthal

et al

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Ra4ioGrapbics

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295

Figures 28, 29. (28) Sonogram shows soft-tissue mass in the gallbladder fundus (arrow) be carcinoma. Multiple calculi were also present. (29) In a sonogram of a large aneurysm ic artery, thrombus (arrows) appears similar to the mass seen in Figure 28.

Focal

thickening

of the gallbladder

that (A)

proved of the

to hepat-

wall

occasionally occurs in cholecystitis, but it is more commonly associated with adenomyomatosis, gallbladder carcinoma (Fig 28), and adherent turnefactive sludge (3 ,8) We en.

countered hepatic

pearance

a case artery

in which

aneurysm

of a gallbladder

thrombus mimicked

mass

in an the

(Fig

ap-

29). .

:; Figure titis

30 shows

Sonogram areas

gallbladder wall (arrows) caused by focal calcium

296

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et a!

of a patient

of increased

with

cholecys-

reflection in the . This appearance was

deposits.

Volume

10

Number

2

31. Longitudinal (a) and transverse (b) scans of a 60-year-old man with emphysematous choledemonstrate extensive gas collections in the gallbladder wall (arrows). (c) Radiograph helped the findings, and the diagnosis of porcelain gallbladder was ruled out. Biliary air (arrows) is also

Figure cystitis confirm

seen.

U

GALLBLADDER

Irregular

WALL

thickening

of the

and surface epitheliurn may give rise to areas

reverberation .

ance

(Fig

may

30) . More

or faint calcium

deposits

have

a similar

appear-

extensive

produce

a “porcelain

which

acoustic

shadowing

obscures

the

gan. Sonographically, cult to distinguish and intra!uminal matous

cholecystitis

March

1990

shadowing

focal

posits wall

Emphysematous chobecystitis is generally caused by occlusion of the cystic artery with secondary gallbladder infarction. There is a high potential for perforation, peritonitis, and sepsis. Twenty percent of the patients are diabetic, and men are affected three times more often than women. Clostridium, Enterobacter aerogenes, and Escbericbia

wall

in adenornyomatosis of increased reflection,

artifacts,

(3 ,8) Occasionally, in cb.olecystitis

ECHOES gallbladder

detail

calcium

de-

gallbladder,”

from of the

in

the calcified rest

of the

coli are ganisms

the most (1,3).

commonly

associated

or-

or-

these findings are diffifrom the extensive mural air collections of emphyse(Fig

31).

Rosenthal

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297

32.

Figures

33.

32-35.

(32)

Sonogram

of a case

of early

rupture

of a gangrenous

cholecystic fluid collection (arrows) . (33) Right longitudinal shows a similar fluid collection (arrows) around a normal tient demonstrates a penicholecystic abscess (A) produced jacent wall of an otherwise normal gallbladder (GB) . (35) cystic abscess (A) secondary to gallbladder (G) perforation

scan gallbladder.

of a case (34)

by a perforated

gallbladder

reveals

small

of perforated duodenal Sonognam of a different

ulcer

Sonogram of another that appears similar

and thickening patient to the

shows abscess

penulcer pa-

of the ada penicholeseen in Fig-

une 34.

U PERICHOLECYSTIC FLUID Gangrene on rupture of an acutely inflamed gallbladder may produce penicholecystic fluid collections or frank abscesses (Figs 32, 35). Such fluid collections appear similar to the lucent halo seen in many cases of cholecystitis (Fig 32) Perforated ulcers may mirnic this appearance (Figs 33, 34). .

298

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et a!

U

EXTRAHEPATIC

BILE

DUCT

DILATATION US is an

excellent

method

for

evaluating

the

size of the extrahepatic bile ducts. Longitudinal scans obtained with the patient in the right anterior oblique (RAO) position are particularly useful and may reveal not only the diameter of an enlarged bile duct but at

Volume

10

Number

2

36

37.

Figures

36,

37.

(36)

Sonogram

clearly

shows

calculus (arrowhead) in the common bile duct shows a calculus impacted in the intrapancreatic obstructing

there would

stone

(arrow)

. This

is a much lesser degree be the case if the stone

produces

of acoustic were

still

decreased

mismatch suspended

dilated

extrahepatic

bile

with a definite acoustic portion of the common stone

echogenicity

between

duct

(arrows)

and

an obstructing

shadow. (37) Transverse scan bile duct. No bile surrounds and

the calculus

reduced

shadowing,

and surrounding

the

since

pancreas

than

in bile.

times the (Fig 36)

cause

of the

enlargement

as well

In the case illustrated in Figure 36, the obstructing calculus that caused the dilatation was easily seen; however, sonographic detection of common bile duct stones can of.

ten

be more 37. Although ally implies

difficult,

as in the

case

shown

in

Figure

duct

may

not return

spite

relief

of the

case

-

who underwent

-

t

longitudinal

cholecystectomy

scan

a dilated obstruction,

for

the

common bile a previously

to normal obstruction.

patient

duct

caliber Such

in Figure

usudilated

38.

dewas

the

Occasional-

of a patient

demonstrates

a persistent dilated common bile duct (arrows). Because the intrahepatic bile ducts were not enbarged, the radiologist suspected no acute obstruction was present. This was confirmed by means of ERCP.

March

1990

Rosenthal

et a!

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Ra4ioGrapbks

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299

a. Figure

b. (a) RAO longitudinal scan of a patient with acute tic duct (CD) . An enlarged common hepatic duct was suspected rant dilatation of the intrahepatic bile ducts. GB = gallbladder. common hepatic duct of normal size (arrows). 39.

ly, an enlarged cystic duct may be mistaken for a dilated common bile duct (Fig 39) . A careful US examination, and correlation with the size of the intrahepatic ducts, should help establish the correct diagnosis.

Choledochab rysm

or diverticuburn

duct.

Anomalous

and

300

U

cysts

RadioGrapbks

pancreatic

usually of the

union ducts

U

Rosenthal

form

as an aneu-

common

bile

of the common allows

pancreatic

et a!

cholecystitis shows a massively dilated cysinitially; however, there was no concomi(b) Another longitudinal scan reveals a

zyrnes to weaken the bile that are found after birth.

duct in most Sonographically,

the cysts may resemble an enlarged den. However, they are commonly close to the head of the pancreas quently (50% of cases) associated

hepatic

bile

bile

helpful

in the

en-

Stasis within various

duct

dilatation.

differential

cases

gallbladfound and are frewith intra-

These diagnosis

facts

are

(1-3).

of bile may result in stone formation the cyst. Figures 40 and 4 1 illustrate appearances of choledochab cysts.

Volume

10

Number

2

.

--

40c.

_

..

41.

Figures 40, 41. (40) Transverse (a) and longitudinal (b) sonograms of a child with intermittent pain in the right upper quadrant show a choledochal cyst (C). The cyst deforms the pancreatic head (F) and contains a calculus (arrow in b) . (c) ERCP image of the same patient shows the large cyst (C) to the left of a normal-sized gallbladder. (41) Sonogram of a choledochal cyst in a 35-year-old woman with moderately severe dilatation of the intrahepatic bile ducts. In this case, the cyst is a large fluid-containing mass (C) anterior to the night kidney and lateral to the pancreas.

March

1990

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et a!

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301

Figures 42, 43. (42) Right child with rhabdomyosarcoma tis shows

tubular,

the periphery intrahepatic scan

transverse scan of a of the porta hepa-

fluid-containing

structures

of the liver, characteristic bile duct dilatation. (43a)

of a patient

without

biliary

disease

in

of major Transverse demon-

strates an anomalous H-type branching of the right portal vein (A = anterior branch, P posterior branch) . This appearance should not be confused with the parallel track sign formed by the dilated right hepatic duct. (43b) Duplex Doppler image definitively demonstrates the venous nature of both the anterior and posterior tubular structures. , :.

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Figure 44. underwent

Transverse a Whipple

scan of a patient operation shows

who typical,

brightly echogenic, branching ducts containing air (arrows) , which are usually most apparent the nondependent portion of the liver.

302

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in

Volume

10

Number

2

a. Figure cystitis.

tient stone passage

b. 45. The

(a)

Sonogram gallbladder

shows a fistula (S) is present of the

stone

U INTRAHEPATIC DILATATION Major intrahepatic

duces

obvious,

ing structures (Fig 42) The irregular, and .

shows is not

(arrow) within

typical

visualized.

findings (b)

Image

of biliary from

air (arrows) an upper

in a patient

gastrointestinal

with

clinical

study

of the

between a severely contracted gallbladder and the duodenal the duodenum, and there is a duodenal stricture (arrowhead)

cholesame

pa-

cap. A large , which prevents

distally.

BILE

DUCT

of the sphincter of Oddi or a surgical bibiaryentenic anastomosis (Fig 44) Bouveret syndrome is another rare cause of bile duct air. In this syndrome, a large gallstone erodes into the distal stomach or proximal duodenum, producing gastric outlet obstruction (Fig45) (1). Rarely, extensive calcification of the intrahepatic arteries closely mimics the sonographic appearance of biliary air (Fig 46). .

bile

large,

duct

tubular,

dilatation

pro-

fluid-contain-

in the periphery of the liver bile duct walls are often mildly they tend to have associated

posterior acoustic enhancement. Dilatation of the right hepatic duct as it courses antenior to the portal vein often produces a “parallel track” sign on transverse scans near the hilurn of the liver. However, this appearance should not be confused with that of anornabus branching patterns of the night portal vein (Fig 43). Air within a dilated intrahepatic biliary system is usually secondary to incompetence

March

1990

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a. Figure patient veals

.

-

b. 46. with that

(a) Sonognam chronic renal

these

areas

are

demonstrates brightly echogenic areas similar failure and severe secondary hyperparathyroidism. extensive

calcification

Intrahepatic bile duct dilatation is usually secondary to obstruction of the extrahepatic biliary system. When the extrahepatic ducts are normal, the intrahepatic obstruction is usually secondary to cholangitis or liven neoplasia, either primary or metastatic (Fig 47). In Minizzi syndrome, the mass obstructing the biliary tract is a large impacted calculus in the cystic duct, which compresses the common hepatic duct (1 ,3). Figure 48 illustrates the various radiobogic findings in Mmizzi syndrome.

of the

intrahepatic

in appearance to biliary air in a (b) Noncontrast CT scan re-

arteries.

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47. Transverse scan of a patient infiltrating cholangiocarcinoma

with a in the

lateral segment of the left hepatic lobe (arrows). The presence of focally dilated bile ducts (arrowheads) is a useful clue to the presence of the mass.

304

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Figure 48 (a) Right longitudinal tion of the intrahepatic bile ducts. casting an acoustic shadow across (c) Right angiogram

March

parasagittal

reveals

1990

MR image

severe

narrowing

sonogram of a patient with Minizzi syndrome shows (b) Sonogram obtained more medially shows a large the ports hepatis. The gallbladder (GB) is contracted demonstrates

findings

of the common

similar

hepatic

to those

duct

in a and

b. (d)

moderate dilatacalculus (arrow) and thick walled. Percutaneous

chol-

(arrow).

Rosenthal

et a!

U

RadioGraphics

U

305

Figure

49.

(a)

patient

with

Canoli

Right

longitudinal

disease

shows

sonogram multiple

of a con-

necting tubular structures (arrows) in the liver. (b) Transverse scan shows a large poorly echogenic calculus (arrow) in the common bile duct. (c) Cholangiogram demonstrates the stone (S).

Caroli disease is a rare form of intrahepatic bile duct dilatation characterized by marked saccular enlargement of the intrahepatic bile ducts and renal disease, usually tubular ectasia or other cystic disease (Figs 49, 50). Hepatic fibrosis and biliary calculi are common (1 -3 ,9) . The absence of tubular connections

between

the cysts

helps

in the differentiation

of autosomal dominant polycystic ease (Fig 5 1) from Caroli disease.

306

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liver

dis-

Figure 51 Sonogram tic liven disease shows tween the cysts, unlike Canoli disease.

U

PERINATAL

of a patient with polycysno tubular connections besonographic findings in

AND

NEONATAL

BILIARY DISEASE Cholelithiasis in the fetus is extremely (Fig 52) . Although fetal cholelithiasis

be idiopathic, hernolytic

there anemia,

is an association such

with Rh incompatibility, (10,11). Although distinctly thiasis

is being

rare

may with

as that

and

associated

enzyme

uncommon,

recognized

choleli-

more

frequently

in premature infants undergoing treatment for respiratory distress and bronchopulmonary dysplasia

Volume

defects

prolonged syndrome in inten-

10

Number

2

d.

C.

Figure 50. demonstrate

Radiologic

studies

less massive biliary show multiple communicating and cholangiognam (d).

of a 1 7-year-old

patient

with

dilatation than that seen hepatic cystic structures.

Caroli

disease

and

osteogenesis

in Figure 49. Right longitudinal These findings are confirmed

imperfecta

sonograms on a CT scan

(a, b) (c)

52. Oblique coronal scan of the night side of a 39-week-old fetus shows multiple, brightly echogenic calculi (arrow) in a normalsized gallbladder. Figure

March

1990

Rosenthal

et a!

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I

i: 53.

54.

Figures

53, 54.

(53)

Sonogram

of a 4-month-old

premature

infant,

who

shows typical findings of cholelithiasis (arrows). (54) Right longitudinal peritonitis who had recently eaten shows what appears to be a stone-filled den (arrow) . Scans obtained after fasting revealed a normal gallbladder cation.

sive care nutrition

units. Prolonged total parenteral and frequent administration of fur-

osernide

may combine

with

the immaturity

of the hepatocellular enzyme system to predispose these infants to gallstone formation (3) (Fig 53) . Although these stones may spontaneously resolve with institution of a normal diet and discontinuation of diuretics, while they are present, the patients are at risk

of chobecystitis

If sonography whose

and

gallbladder

cent

meal,

bibiary

is performed is contracted

the penitoneal

due

plaques

to a ne-

urn peritonitis may closely mimic the appearance of a small gallbladder filled with calculi or a diffusely calcified gallbladder (Fig 54) . US visualization of a normal gall-

bladder

after

fasting

as well

and radiographic evidence plaques elsewhere in the can clarify this situation. US has sive

biliary biliary

an

adjunctive

differentiation

role

in the

of neonatal

atresia in jaundiced scintigraphy is the

infants. primary

noninva-

Hepatoimaging

US may

rube

out

abize

bile

U

Rosenthal

et a!

dilatation.

meconium galibladcalcifi-

the

true, however, present in up hepatic biliary

pres-

portions and to

Failure

on sonograrns

neonate

of biliary

to visu-

in a fast-

is presumptive

atresia. since to 20% atresia

cvi-

The converse

is not

the gallbladder is of patients with extra(1 ,3) (Fig 55).

and

obliteration.

Eventually,

progressive

biliary cirrhosis and hepatic failure occur. The disease occurs in 1 %-4% of patients with chronic ulcerative colitis. There are

weaker Crohn

diagnosis

RadioGrapbks

duct

jaundiced

bolic

U

to evaluate

the gallbladder

associations with Riedel disease, and retnoperitoneal

The most conditions

308

be useful

ence of the gallbladder, to visualize of the extrahepatic bibiary system,

duct

cavity

hepatitis

of 1 kg,

U SCLEROSING CHOLANGITIS Primary sclerosing chobangitis is an idiopathic cholestatic syndrome characterized by intra- and extrahepatic biliary fibrosis and bile

as sonographic

of calcific penitoneal

tis,

dence

of meconi-

weight

tool, since passage of the radionuclide into the intestinal tract rules out biliary atresia. However, because this finding may not be demonstrated in some cases of severe hepati-

ing

obstruction.

in an infant

had a birth

scan of an infant with or diffusely calcified and widespread penitoneal

common is most

alteration is one

disease, fibrosis.

etiobogic link likely bacterial

of bile

acids.

of exclusion,

Volume

in these or meta-

Clinically, after

congeni-

10

Number

the

2

.i

1

si..

. .

--

‘

.

.

b.

(a) Right longitudinal scan of a 2month-old infant with biliany atresia jaundiced since 2 days of age shows a normal gallbladder (G) and common hepatic duct (arrow) . (b) Hepatobiliary scintiscan shows activity in the liver and bladder but not the gallbladder on bowel, findings suggestive of biliary atresia. (c) Intraoperative cholangiogram opacifies the gallbladder and a small patent common bile duct but shows no filling of the common hepatic or intrahepatic Figure

55.

ducts, despite transient clamping common bile duct. The diagnosis biliary

ings

atresia

and

was confirmed.

include

den wall,

focal

bile

extrahepatic

duct

tal biliary

disease,

surgical

choledocholithiasis,

stricture,

and

been ruled out. These patients creased propensity to develop well as benign and malignant neoplasms (1,12-15). Although

ination nosing

March

the

of some cholangitis

1990

results

cancer

have an ingallstones as gallbladder

of sonographic

patients with are normal,

prehave

primary reported

cholangitis.

and

(1 6- 1 9)

system,

focal

We a surgically diagnosis

The

of the

thickening biliary

duct,

patients with ically proved vious

thickening

concentric

of the bile C.

of the proximal of intrahepatic

.

patients

gallblad-

of the intrairregularity

dilatation

of the

encountered eight or cholangiographof primary sclerosing

ranged

in age from

23 to 60 years, with an average of 40 years. Two had past histories of chronic ulcerative colitis. No sonographic abnormalities were

exam-

scbefind-

Rosenthal

et a!

U

RadioGrapbics

U

309

b.

a.

Figure

56.

Longitudinal show striking

cholangitis

(a) and thickening

present

in three.

Mild

to marked

thickening

was seen

ing,

irregularity,

or focal

hepatic bile ducts ening or irregularity duct in two. sonographic tients.

transverse (arrows)

gallbladder

in three;

thicken-

dilatation

in three; and focal of the extrahepatic

Figures findings

(b) sonograms of a 23-year-old of the gallbladder (GB) wall.

56-59

in four

illustrate

of these

1 .

thickbile

Friedman tract, hams

of intra2.

the

pa3.

AC.

a major

part

in the

evaluation

of bib-

iary disease. Although the diagnosis is usualby easily established, there are a number of pitfalls that must be avoided in even this rd. ativeby simple imaging task. The high nesolulion of new US equipment and continued attention to anatomic detail and sonographic differential diagnoses will help improve diagnostic accuracy.

310

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U

Rosenthal

primary

et a!

5.

Kane RA. Goldberg

sclerosing

of the

and spleen.

liver,

biliary

Baltimore:

Wil-

1987.

The biliary system. B, eds. Gastrointestinal

nography. New York: 1988; 75-137. Mittelstaedt CA. The

In: Abdominal

In: Kurtz AB, ultraso-

Churchill liver

Livingstone,

and

ultrasound.

Livingstone,

MacDonald FR, Cooperbeng The WES triad: a specific

1 987;

biliary

sys-

New

York:

1 -162.

PL, Cohen sonographic

MM. sign

of gallstones in the contracted gallbladder. Gastrointest Radio! 1981; 6:39-42. Frazee RC, Nagorney DM, Mucha PJr. Acute

acalculous 1989;

6.

Radiology

pancreas, & Wilkins,

Churchill

4.

CONCLUSION

US plays

with

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(c, d) Longitudinal and transirregularity, and focal dilatation of the common hepatic duct (arrow in C) ducts (arrows in d) . (e) ERCP image demonstrates multiple areas of steno-

verse scans show thickening, and in the left lobe intrahepatic sis and dilatation.

wall

c.

cholecystitis.

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Scanlan K, Cullenward M, Pozniak M. Gallbladder wall thickening after bone marrow transplantation. Presented at the 32nd Annual Meeting

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-

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‘;

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Sonogram

sclerosing

of a 46-year-old

cholangitis

reveals

thickening and dilatation of the intrahepatic bile ducts (arrows) and moderate thickening of the gallbladder wall (arrowheads). (58) Longitudinal scan ofa 32-year-old woman with primary sclerosing cholangitis demonstrates thickening and irregularity of the common hepatic duct (arrows). (59) Longitudinal sonogram of a 4 1 -year-old man with ulcerative colitis and primary sclerosing cholangitis depicts mild dilatation and slight thickening of the intrahepatic bile ducts (anrows).

59-

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Chapman RW. Primary sclerosing cholangitis.JHepatol 1985; 1:179-186. Lillemoe KD, Pitt HA, Cameron JL. Sclerosing cholangitis. Adv Sung 1987; 21:65-92. White U, Hart MJ. Primary sclerosing cholangitis. AmJ Sung 1987; 153:439-443. Brandt DJ, MacCatty RI, ChanboneaujW, LaRusso NF, Wiesner RH, LudwigJ. Gallbladder disease in patients with primary sclerosing cholangitis. AJR 1988; 150:57 1574.

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Dayton MT, Longmire WPJn, Tompkins RK. Caroli’s disease: a premalignant condition? AmJSurg 1983; 145:41-48. Beretsky I, Lankin DH. Diagnosis of fetal

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Orleans, October 6-9, 1987. Berk RN, van den VegtJH, LichtensteinJE. The hyperplastic cholecystoses : cholesterolosis and adenomyomatosis . Radiology 1983;

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Sclerosing

cholangitis : sonographic demonstration of bile ductwall thickening. AJR 1982; 139: 1016-1018. Vrla RF, Gore RM, Schachter H, Craig RM. Ultrasound demonstration of bile duct thick-

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sclerosing 1986; Ultrasound

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