Carol

C. Coleman,

MD

Thermal

Jack

#{149}

A. Vennes,

Ablation

I

P. Posalaky,

MD

Kurt

#{149}

180:363-366

Amplatz,

T

humans. We hypothesized that ablation of the gallbladder could be achieved through complete destruction of the gallbladder mucosa by a thermal injury. Because of its ready availability, U.S. Food and Drug Administration-approved

diology,

University

ceived December

of Radiology (CCC.), Internal Medicine (J.A.V.), and Pathology (I.P.P.), Center, 1 Veterans Or, Minneapolis, MN 55417; and the Department of Ra-

of Minnesota,

Minneapolis

(K.A.).

From

the

1988

RSNA

scientific

assembly.

Re-

4, 1990; revision requested January 23, 1991; revision received March 15; accepted March 18. Supported by a Research Advisory Group grant from the United States Department of Veterans Affairs; the Department of Radiology, University of Minnesota; and the Minnesota Medical Foundation. Address reprint requests to CCC. 0

RSNA,

1991

status,

and

lack of toxicity to humans, hot contrast medium, previously used effectively for the obliteration of spermatic veins in infertile male patients (3942), was used as the ablative substance. The shortand long-term pathologic responses of the gallbladder mucosa to this thermal injury were studied.

MATERIALS Fifteen cluded

AND

adult

METHODS

mongrel

in the study.

dogs

were

In 13 dogs,

in-

hot

con-

trast medium

was injected into the gallbladder; in two control dogs, room temperature contrast medium was used. All dogs were anesthetized by using intravenous injection of barbiturate, and the gallbladder was exposed by a midline laparotomy.

A clamp

was

applied

to the junc-

tion of the gallbladder neck and cystic duct region. Temperature probes (thermocouples) (Shiley, Irvine, Calif) were applied in the liver parenchyma adjacent to the gallbladder and on the surface and in the

lumen

of the gallbladder.

The

digital

temperature display on the three probes was recorded every 15-30 seconds. Timetemperature charts were constructed. A Teflon catheter (7 F) with four side holes was

inserted

through

the fundus

into

the

gallbladder and held in string suture (Fig 1). The pletely aspirated. Three injections of boiling 76% meglumine and sodium

place by a pursebile was cornsuccessive 20-mL

(Hypaque

Drug,

were two

I From the Departments Veterans Affairs Medical

MD

Gallbladder’

is estimated that 15 million women and 5 million men in the United States have gallstones and that 1 million new cases are diagnosed annually. Five to eight thousand deaths per year are attributed to gallstone disease (1). The classic treatment for gallbladder disease is surgical cholecystectomy (500,000 per year in the United States), which has a signfficant morbidity and mortality rate, particularly in older patients (2,3). More recently, surgical cholecystectomy has been challenged by extracorporeal shock wave biliary lithotipsy, chemical dissolution of gallstones, percutaneous removal of gallstones with baskets or a rotary lithotrite, and electrohydraulic or ultrasonic lithotripsy (4-35). With these techniques, however, the diseased gallbladder remains in place, and recurrent stone formation (80% within 15 years [36], 50% in 5 years [371) and cholecystitis, with its potential cornplications, cannot be prevented. Most recently, extracorporeal gallstone lithotripsy and percutaneous gallstone removal techniques have been further challenged by the introduction of laparoscopic cholecystectomy, which causes less morbidity than does surgical cholecystectomy. This procedure, however, cannot be performed in patients with adhesions. The technique may result in serious complications; emergency cholecystectomy has been required in about 5% of cases (38). It was the purpose of this study to develop a nonsurgical method of ablating the gallbladder that could ultimately be applied percutaneously to

Index terms: Gallbladder, calculi, 762.289 Gallbladder, diseases, 762.2891 #{149} Gallbladder, interventional procedure, 762.1229 1991;

Irene

#{149}

ofthe

Gallbladder ablation by means of injection of hot contrast medium was attempted in 13 dogs. Room temperahire contrast medium was injected into the gallbladders of two additional dogs (controls). After midline laparotomy was performed to expose the gallbladder, temperature probes were placed in the liver adjacent to the gallbladder, and on the surface and in the lumen of the gallbladder. A 7-F catheter with multiple side holes was placed into the gallbladder. The cystic duct was clamped during the procedure. After injection of boiling contrast medium, the mean temperature in the gallbladder lumen was 80#{176}C; in the adjacent liver, 43.5#{176}C; and on the gallbladder surface, 45.8#{176}C.After the procedure, the cystic duct was unclamped, temperalure probes and catheter were removed, and the laparotomy was closed in standard fashion. In the hot contrast medium group, one dog each was sacrificed at 2, 4, 8, and 12 weeks, and at 6 months. Six animals were sacrificed at 1 year. The gallbladder was completely ablated in 11 of 13 animals in the hot contrast medium group. One dog was sacrificed at 8 days because of bile leakage, and another was sacrificed at 17 days because of gallbladder rupture. The two control animals were sacrificed at 12 and 13 weeks, and their gallbladders were normal at that time.

Radiology

MD

76%;

Sterling

diatrizoate

contrast

medium New

York)

made

into the gallbladder. The first injections were performed rapidly, with immediate aspiration of the contrast medium, to heat connecting tubing and gallbladder wall. With the third injection, in the first five animals, the application time of hot contrast medium was 5 mmutes. In the fifth animal, the gallbladder ruptured. The application time in the remaining eight dogs in the hot contrast me363

dium

group

There

were

was

series was injections

of the

nique

used

medium,

control

used

After

injection

duct

temperature moved.

the

group

in the

hot

of hot

contrast

was

was

techiden-

contrast

closed

The fascia,

and

with

muscle,

purse-string

medium

were

mal,

the

catheter tightly;

sutures.

one

at 2 weeks, and 6 months,

killed

closed

in

were sacrificed at 12 procedure. In the

group,

after

animal 4 weeks, 8 and six

1 year.

purse-string

the

were regallblad-

and skin were

each was sacrificed weeks, 12 weeks, dogs

and

catheter sites of the

standard fashion. The control animals and 13 weeks after the

contrast

medium,

unclamped,

probes puncture

The

were

hot

The

group.

the cystic

der

ruptures.

once, for a total of six Other than the tern-

contrast

in the

to that

material

to I minute.

subsequent

repeated per animal.

perature tical

changed

no

In one

suture

the

entrance site was not secured this resulted in bile leakage and

necessitated Another

animal

it to be was

sacrificed sacrificed

Figures 1, 2. Temperature

row),

(1) Drawing probes

of the canine

were

on the gallbladder

placed

into

surface

liver liver

(large

2. and gallbladder,

parenchyma

curved

solid

from

adjacent

arrow),

an anteroinferior to the

and

view.

gallbladder

in the gallbladder

(open

ar-

lumen

(straight solid arrow). A 7-F cannula with side holes was placed into the gallbladder lumen (small curved arrows). (2) Line drawing of liver and gallbladder, with range of temperatures and mean (Ji) temperature in the liver parenchyma adjacent to the gallbladder, on the gallbladder surface, and in the gallbladder lumen, during application of hot contrast medium.

ani-

around

1.

at 8 days. on the 17th

day because of gallbladder rupture, presumably from excessive thermal injury. In all animals, the gallbladder and sur-

rounding

liver parenchyma

at necropsy

and

of the

gallbladder,

liver,

were

obtained

When

the

anatomic tion neck

fixed

Sections

and

duct

gallbladder

form

Two

cystic

for histologic

examination.

was

in recognizable

(2-8 weeks),

was taken from of the gallbladder

duct.

was removed

in formalin.

or three

the

a 2-3-mm

fundus, and the

slides

were

sec-

body, cystic

and

made

from

each section. When the anatomic configuration of the gallbladder was not recognizable, the fibrous tissue and surrounding liver parenchyma at the anticipated level of the gallbladder and cystic duct were sampled. Five-micrometer-thick paraffin sections were stained with hematoxylineosin. If small mucicarmine

The apolis imal

study

cysts stain

was

were encountered, was used.

approved

Veterans Affairs Use Committee.

3.

a

the fundus

Center

An-

medium

group,

Group

of the the

hot

contrast

temperature

in

the adjacent liver ranged from 37.4#{176}C to 47.0#{176}C (mean, 43.5#{176}C);on the surface of the gallbladder, from 36.4#{176}C to 61.1#{176}C (mean, 45.8#{176}C);and in the gallbladder lumen, from 60.0#{176}C to 90.8#{176}C (mean, 80.0#{176}C) (Fig 2). The wide temperature fast the

range boiling

was secondary contrast medium

to how

could be aspirated and then injected

from its container through the in-

dwelling

Considerable

catheter.

ing can occur during through the connecting At gross examination, der wall of 2-, 4-, and

364

Radiology

#{149}

markedly

bladders and there

Medium

In the animals

and body

the

section

through

middle

of the gallbladder

of the “gallbladder”

cool-

transfer and tubing. the gallblad8-week animals

thickened.

were was

in a 1-year

The

gall-

normal to small in size, no evidence of perfora-

tion.

At histologic

was

transrnural

animal.

examination, necrosis

there

of the

gall-

fundal tamed

In the body,

Histologically, with cuboidal mucoproteinaceous

The had

sue

chyma.

trate.

a polymorphonuclear

In 12-week,

animals, placed

infil-

6-month,

the gallbladders by fibrous tissue,

and

fibrotic.

In the

neck

of the

gall-

bladder, the mucosa was destroyed, but viable deep glands were present. In three 1-year animals, a small (12-cm)

“cystic”

area

was

animal.

found

ing

the gallbladder

is

a cyst with mucoprotein the cyst. (Hematoxylin-

the cells

the cysts material.

con-

cavities were lined and contained a material (Fig 4).

liver adjacent to the gallbladders scattered fibrotic changes extendseveral

millimeters

into

the

paren-

1-year

were rewith com-

plete obliteration of the gallbladder lumen (Fig 3). In one 1-year animal, the neck of the gallbladder was patent and the remainder of the gallbladder was

fundus, lines

region. Grossly, solid or semisolid

bladder mucosa including the deep portion of glands. The wall of the gallbladder showed granulation tiswith

bed of a 1-year

can be identified. The gallbladder has been completely replaced Liver adjacent to gallbladder bed demonstrates minimal fibrotic stain; original magnification, x 30.) (4) Histologic section through

replaced with fibrous tissue (black arrow). In the is present (white arrow). A monolayer of cuboidal epithelium eosin stain; original magnification, x5.)

was

Contrast

(3) Histologic

completely

RESULTS Hot

3, 4.

No recognizable gallbladder by fibrous tissue (arrows). changes. (Hematoxylin-eosin

by the Minne-

Medical

4.

Figures

in the

Control Both cally cluding contrast

wall. clamping partial vation

Group control normal

animals

a chemotoxic medium on

However,

had

gallbladders

at the

histologi(Fig

5), ex-

effect of the the gallbladder

site

of previous

of the cystic duct, there was loss of the mucosa but preserof the deep glands.

August

1991

ing cannulas hot contrast the cannula tact

between

the

hot

contrast

medium

glands.

bladder in eight same technique

unclamped before the closed. After ablation,

sclerosing

----

5. Histologic section of the gallbladder in a 12-week mal. The gallbladder mucosa matoxylin-eosin stain; original x30.)

through body control aniis normal. (Hemagnification,

Figure

patients developed

Various alcohol,

dium

tetradecyl

hot

by

using the in animals:

used

in gallbladder

been

completely

Neither

tetracycline,

or alcohol with sodium carbonate,

medium)

have

ablation;

Solomowitz

has

(43-48).

et al nor

man et a!, who used dium, stated whether

been

none

successful

the

which

is required

protein

the

electrocoagulation

tempted

is un-

(49),

gallbladder

porcine

model

ablation

with

the

cys-

the

at-

in a

sclerosants

mucosa

and

muscularis.

The serosa was not always affected. Thirteen of 16 gallbladders monitored for 5-11 weeks had complete obliteration, with replacement by fibrous scar. However,

five

had “nests cysts lined thelium.

The

in the

ence

occasionally

or small of epi-

of obliteration

to be caused of sclerosants contact of the

fundal

area

We

(Coleman

Volume

failures

of the Foley

plication. 1988)

of these

of epithelium” with a monolayer

were thought concentration of adequate

when

180

the

2

pres-

approblem

data,

long-term

Number

#{149}

of the

during latter

unpublished

using

by lower and lack sclerosant

because

balloon

noted

CC,

whereas

to the

indwell-

deep

heat

layers,

sclerosing

and

agents

deof

is con-

the

diseased

failure

of the

human

technique

which

were

by the chemical The denaturation is similar to that

likely

in the

mucosa sinot

heat

which

affected

gradient

from

is also

con-

creates the

a tern-

mucosa

to

the serosa of the gallbladder. By varying temperature and application time, the depth of injury can be controlled, deeper

in the

glands

destruction

in the

of the

gallbladder

source through a predetermined ternperature by relying on heat convection (unpublished data). We selected to aspirate the gallbladder content and replace it with hot contrast medium, which ensures a global thermic injury to the gallbladder wall. Also,

of the spares The medium dia are significant

can be readily which allows

seen filling

gallbladder and cystic duct, but the common bile duct. rationale of using hot contrast was threefold: Contrast meFDA-approved and have no systemic

toxicity

and

are

readily seen fluoriscopically, which allows filling of the gallbladder and the cystic duct and spares the corn-

may

of ablation

be possible

electrocoagulation

“cyst”

was

Each

plications tam. The externally The only the

of the

cys-

found

cavity

in the

was

of cuboidal The exact

fun-

lined

with

a

or columnar cause and im-

of this finding are uncergallbladder was not drained following the procedure. egress for the necrotic debris cystic

duct.

It is likely

that

humans, the gallbladder therefore would have to be drained externally until fibrosis ensued and the gallbladder shrunk. In one 1-year animal, the neck of

the gallbladder the body and

remained patent and fundus were fibrotic.

The histologic to those found

ment

without causing complete gallbladder necrosis. Theoretically, this goal could be achieved by heating the gallbladder content with an intravesicular heat

contrast medium fluoroscopically,

but was did

debris in the fundus of the gallbladder did not drain and became encapsulated as the gallbladder shrunk. In

of protein by heat caused by sclerosing

However,

gallbladder

was

agent.

by tissue,

agent

abdomen the mucosa

of the

single layer epithelium.

is likely

due to regeneration of the from deep Aschoff-Rokitansky

the cysthe ap-

contrast

there was no regeneration from the cystic duct,

1-2-cm

model

gallbladder

hot

cause mucosa

dal area.

producing

in a porcine

of the

study, during

tic duct, which is a tedious procedure requiring 2-3 weeks until an endoluminal scar is formed in the cystic duct. In three 1-year animals, a small

is not agents layers

plication

without

with

finding

the

resulting

ethanol and sodium tetradecyl sulfate (50). After 2 weeks, four specimens had chronic inflammatory changes and necrosis. The depth of necrosis included

This

gallbladder,

electroco-

obliterated

chemical superficial

perature

the

known. Becker et al, after occluding the tic duct with endoluminal radio-frequency

technique.

agents.

mucosa,

be

In this experimental tic duct was clamped

not regenerate, even in the presence of a patent cystic duct, which suggests that mucosal regeneration must occur from undestroyed deep glands. Be-

duct was uniresidual galla mean months averthat the gall-

surprising, since nature only the

60#{176}C, ducted

to denature

to destroy

cannot

nuses,

Getrajd-

hot contrast methey measured

temperature in the gallbladder (43-45). Whether the temperature used in those studies was above

Although

duct with

a transmural coagulation necrosis. The discrepancy between the better experimental results obtained with

agents (absolute sodium, so-

sulfate,

contrast

bladder

ducted

sclerosing 5% morrhuate

methyl cyanoacrylate trifluoroacetic acid,

agents.

agulation of the cystic formly successful, the bladder volume after follow-up period of 5 aged 10 cm3, indicating their

DISCUSSION

mon bile duct. Also, the depth of injury can be controlled by temperature and application time, resulting also in the destruction of deeper mucosal

and the fundal area where the cannula was positioned. In a more recent study, Becker et al (51) attempted ablation of the gall-

electrocoagulation of the cystic and ablation of the gallbladder

_

and

for administration of the medium. The flange of prevented adequate con-

of the

animals.

but

findings in the

cystic

were clamped

duct

in the other

The

mucosa

was

the deep

glands

were

was likely due of the gallbladder

cystic

duct,

sualizing

destroyed,

viable.

This

to accidental clamping neck instead of the

caused the

identical seg-

cystic

by difficulty duct

in vi-

at laparot-

omy. This technique, used in humans taneous approach

therefore, could be undergoing a percufor nonsurgical

treatment of gallstones and concomitant gallbladder disease. Gallstones could be removed by means of extracorporeal shock wave treatment, ultrasonic

tion,

lithotripsy,

or mechanical

chemical

dissolu-

extraction,

and

ablation of the gallbladder could low. With this new technique, a

transhepatic puncture formed

trast cavity.

single-wall would to avoid

medium In the

fol-

gallbladder

have to be perspillage of hot con-

into event

the

peritoneal

of accidental

Radiology

per-

365

#{149}

foration,

external

instituted

until

drainage the

hole

could sealed

be over.

Filling of the gallbladder would have to be continuously observed fluoroscopically,

and

overdistention

would

have to be avoided to spare thermal injury to the common bile duct. Because of the valves of Heister and sphincter of Oddi, this may be feasible. The gallbladder rupture in one animal may have been caused by transrnural necrosis of the gallbladder wall. This complication may be avoided by use of temporary external gravity drainage (ie, negative pressure). Local anesthesia of the skin and subcutaneous tissue around the drainage tube and prior instillation of 4% lidocaine into the gallbladder or a celiac plexus block may preclude use of general anesthesia. Once more experience has been gained, this procedure could be performed on an outpatient basis. This proposed thermocholecystectorny rnethod would have a major economic impact on the treatment of gallbladder disease by eliminating general anesthesia, shortening hospitalization

period

time,

and

8.

decreasing

9.

10. 11.

12.

13.

14.

16.

17. 18. 19.

the 20.

ADDENDUM Since the writing of this article, one human patient has undergone successful percutaneous

thermal

gallbladder

abla-

tion. Acknowledgments: and Chet Sievert

unending

patience

I thank for the hours

they gave

Bonnie Abeyta of work and the to us and this

project.

1.

2. 3.

4. 5. 6. 7.

21.

22.

23.

24.

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c

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49.

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