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1007
Treatment of Bile Duct Stones Laser Lithotripsy: Results in 12
by
Patients
Steven
We used a pulsed tunable dye laser(operating
L. Dawson1
Peter
R. Mueller1
Michael J. Lee1 Sanjay Saini1 Peter
Norman
Kelsey2
S. Nishioka2
to fragment
large
in 12 patients
(0.8-4.5
after
cm) stones
at 60 mJ per pulse, 504-nm wavelength) in the hepatic ducts or common bile duct to extract stones via a T-tube or endo-
retained
cholecystectomy.
Attempts
scope had been unsuccessful were successfully eliminated occurred
but
developed
in all patients. In nine of 12 patients, all stone fragments during the initial treatment. In one patient, fragmentation remained, requiring endoscopic stenting. Pseudomonas sepsis
debris
in this
patient
30 days
after
the
procedure
the stone fragments. Fragments remaining sifting by using saline flushing or endoscopic of
12
patients,
the
treatment
was
and
was
after lithotripsy or percutaneous
unsuccessful
treated
by extraction
of
were cleared at the same basket extraction. In two
because
of
laser
malfunction.
The
treatment was performed without complications, except for clinically insignificant hyperamylasemia, which occurred in two patients. Our experience suggests that laser lithotnpsy offers a safe alternative for nonsurgical treatment of large retained biliary stones for patients in whom traditional treatments have failed. AJR
158:1007-1009,
Traditional percutaneous
May
1992
therapy for stones retained in the common bile or endoscopic basket extraction. Newer techniques
corporeal
shock-wave
methods
fail or cannot
lithotripsy
(ESWL) or electrohydraulic
be performed,
surgical
duct has been include extra-
lithotnipsy.
reexploration
When these
of the duct
has been
necessary. Recently, tunable dye lasers have become available to fragment stones in the urinary tract and the common bile duct [1]. We present the results of fragmentation of stones retained in the intrahepatic duct or common bile duct by use of laser lithotripsy via T-tube tracks or endoscopic methods in 12 patients in whom standard percutaneous or endoscopic basket extraction was unsuccessful.
Subjects
and Methods
Laser lithotripsy removal Received August 5, i99i sion December 23, 1991.
; accepted
after
revi-
eral Hospital, Harvard Medical School, 32 Fruit St., Boston, MA 02114. Address reprint requests to S. L. Dawson. 2 Department setts
General
and
one
of Gastroenterology, Harvard
Boston, MA 02114. 0361 -803X/92/1 585-i 007 © American Roentgen Ray Society
MassachuMedical
School,
was
fluoroscopic sedation
stones
by the hospital’s an
outpatient.
guidance. with
of cholangitis gentamicin.
Hospital,
biliany
in 12 patients in whom percutaneous was
unsuccessful.
Six
women
or endoscopic
and
One patient
midazolam was Routine
institutional The
and
was
had epidural
sublimaze.
board. done
anesthesia,
Antibiotics
present.
When
necessary,
liver
function
tests
were
IV antibiotics and
measurements
4.5
cm
in diameter.
One
after the procedure.
Patients
patient
stones;
Eleven
in the
patients
radiology given
were of
given, serum
between
were
inpatients
department
but all others not
men
under
were treated
unless
clinical
typically amylase
by IV
evidence
ampicillin levels
and were
had one to three stones, from 0.8 to two patients had intrahepatic stones. T-tube tracks were used for access in seven patients, endoscopy in five. A tunable dye laser (60 mJ per pulse, 504-nm wavelength, 1 Hz, 3-sec pulse length; Candela Laser Corporation, Wayland, MA) was used to fragment the stones. The laser pulses performed
on all patients
review
procedure
basket 52 The laser treatment
six
and 89 years old were included in the study after giving informed consent. was approved
Presented at the annual meeting of the American Roentgen Ray Society, Boston, MA, May 1991. I Department of Radiology, Massachusetts Gen-
was performed
of retained
had
calcified
1008
DAWSON
ET
AL.
AJA:158,
May 1992
Fig. 1.-Use of choledochoscope for direct visualization during fragmentation of a stone in distal common bile duct. A, Cholangiogram obtained via safety cathe-
Downloaded from www.ajronline.org by 186.182.130.56 on 11/02/15 from IP address 186.182.130.56. Copyright ARRS. For personal use only; all rights reserved
ter shows relationship
of stone to choledocho-
scope before laser fiber is introduced. B, Cholangiogram shows laser fiber (arrow) extending beyond tip of choledochoscope to contact stone.
were stone. seven An
conducted by a 0.4-mm-diameter quartz fiber passed to the The number of pulses used to fragment the stones varied from to 420. 8.5-French ACMI choledochoscope (American Cystoscope
Manufacturers
Inc.,
Boston,
MA)
was
inserted
through
the
T-tube
track to visualize the stone in seven patients (Fig. 1). A double endoscope system (1 6-mm-diameter “mother” scope with “daughter” endoscope
placed
through
5.5-mm
was used in all five endoscopy tomies
to
patients,
allow
stones
stone basket. tioned
or
of
the
the
wall
of
remaining flushed
from
channel
“daughter”
In two
intrahepatic,
the stone was posicommon
fiber contact
after lithotripsy
were extracted
the
injections
duct
scope)
had papillo-
endoscope.
eight patients,
the
of mother
These patients
with the fiber by using a modified
bile duct to allow consistent
Fragments kets
placement
were held in contact
In the remaining
against
common
working
patients.
with
of
hepatic,
on
with the stone. with stone
saline
or
bas-
contrast
material. After lithotripsy, the ducts were temporarily drained with a T-tube or nasobiliary tube until follow-up cholangiography showed no residual debris. In five patients who were treated with endoscopy,
fluoroscopic
guidance
for laser placement
was confirmed
with direct
vision as well as
Stones
were successfully
subsequent
basket
fragmented extraction
in 10 patients,
of all fragments
per-
in eight
patients, or saline flushing of all fragments into the duodenum in one patient. In nine patients, the duct was free of stone debris
at the conclusion
tients, mechanical cessful Iithotnpsy; was
attempted.
of the initial
procedure.
In two
pa-
failure of the laser system precluded sucprocedures were aborted before lithotripsy One of these
patients
subsequently
went laparotomy and exploration of the common and multiple stones were removed.
under-
bile duct,
In one patient, several stone fragments remained lithotripsy and could not be removed with endoscopic kets. An 1 1 .5-French Amsterdam stent was placed
after basendoscopically. One month later, the patient returned with Pseudomonas sepsis and duodenal erosion by the stent. The stent
was endoscopically were
basketed
368
pulses.
without
removed, further
No attempts
were
made
to characterize
peak postprocedural amylase level was 1 987 units (normal, 43-1 1 5 units). One patient who underwent lithotripsy (via T-
tube track) of three stones peak postprocedural
Two
patients
amylase
had stones
patients were treated at the initial treatment
from 1 to 2 cm in diameter
had a
level of 503 units.
in the intrahepatic
successfully session.
with
ducts:
removal
both
of all debris
Discussion
Stones retained in the common bile duct are a common problem in biliary surgery. When these stones are less than 1 cm in diameter,
Results mitting
quired
fragments for stone composition. Clinically insignificant hyperamylasemia developed in two patients after lithotripsy. In one patient who had pancreas divisum and an 8-mm intrahepatic duct stone and in whom both radiologic and endoscopic approaches were used, the
was used, and positioning
was verified by correlating the intraprocedural cholangiogram with the fluoroscopic image. Laser lithotnipsy was then performed under direct vision using a “mother-daughter” endoscope configuration.
Stone disintegration cholangiography.
Stone size did not correlate with the number of pulses necessary for fragmentation: one 1 -cm stone required seven pulses, whereas a similar-sized stone in another patient re-
and all remaining complication.
fragments
they can often
be extracted
through
T-tube
tracks by using steerable catheters. If no T-tube is present when the stone is found, endoscopic papillotomy with basket or balloon extraction can be performed. These two techniques should be successful in approximately 90% of patients who have small stones. Dissolution with agents such as methyl tert-butyl ESWL
ether (MTBE) is not an option for intraductal stones. has been used to treat stones in the common bile
duct [2-4] and was available in our institution during the time laser lithotripsy was studied. Although the actual lithotripsy session is noninvasive, patients require a papillotomy for passage of stone fragments, and, if fluoroscopy is used for localization, a nasobiliary catheter or percutaneous tube must be used to opacify the system. These supplementary proce-
dures make ESWL more invasive than it appears to be. Also, targeting of stones is very difficult if sonography is used for localization. With water path, rather than water bath, ESWL, the requirement for anesthesia is lessened, but IV sedation and analgesia is still necessary. ESWL also frequently requires several sessions until patients are free of stones, whereas
LASER
AJA:i58,
May 1992
TABLE
1: Comparison
Downloaded from www.ajronline.org by 186.182.130.56 on 11/02/15 from IP address 186.182.130.56. Copyright ARRS. For personal use only; all rights reserved
Study
of Published
Studies
Total No.
No. (%)
of Patients
Fragmented
LITHOTRIPSY
on Laser
OF
BILE
DUCT
STONES
1009
Lithotripsy
N 0. (%) Completely Cleared
No. (%) with
Immediate
Single-Session Success
Complications
Subsequent
Subsequent
Surgery
ESWL
Cotton et al. [7]
25
23 (92)
20 (80)
12 (48)
1 (bleeding)
3
2
Ponchon
25
22 (88)
22 (88)
1 1 (44)
3 (bacteremia)
2
1
1
0
et al. [9]
1 (duct
Present study
12
Note.-ESWL
10 (83)
cx tracorporeal
=
sh ock-wave
9 (75)
ESWL,
wave
there
travels
across
is a risk of injury
intervening
to those
stone clear1). Because
organs
organs,
during
a factor
that
is not of concern during intracorporeal lithotripsy with pulsed dye lasers. Pulsed dye laser lithotripsy offers a new nonsurgical option for patients in whom these other methods have failed, are unavailable, or are inappropriate. When a stone is struck by a laser pulse, the very high energy
density
surface,
rapidly
causing
raises
ionization
tion of a plasma
state
the temperature
of the stone
of atoms and inducing
above
the stone
surface.
the forma-
As the plasma
expands, an acoustic wave is formed that fragments the stone. Thus, for most effective fragmentation, the tip should be on or very close
to the surface
of the stone.
With endoscopic or radiologic methods, stones in the intrahepatic and common bile duct can be localized, immobilized, and fragmented by using pulses of laser energy transmitted to the stone surface by optical fibers [1 5-9]. The laser fiber itself measures only 0.2 mm in diameter, while the fiber plus covering measures 0.4 mm in diameter. It is easily placed ,
through
a small
sheath
2- to 4-French
many cases fluoroscopy ing the
fiber,
in this
in size.
alone might be suitable series,
direct
visualization
Although
in
for monitorthrough
a
choledochoscope or endoscope was used. The method allows fracturing of large stones into fragments small enough to permit
subsequent
nonoperative
removal,
but whether
the
stones were approached through the T-tube track or endoscopically, secondary maneuvers were required to remove the stone fragments: the stones approached through the Ttube track were either and stones approached
basketed or flushed out endoscopically required
of the duct, papillotomy
and either basket extraction or balloon expulsion into the duodenum. Earlier endoscopic or radiologic attempts at stone removal had failed in our patients because of the size of the retained stones. ESWL was not attempted in these patients. The smallest stone fragmented in this series was 0.8 cm in diameter,
and the largest
green tunable 1 0 patients
session necessary
was
4.5 cm. The use of the coumarin
dye laser allowed and
removal
successful
of stone
in nine of the 1 2 patients. for fragmentation
2 (hyperamylasemia)
lithotripsy.
laser lithotripsy has a 45-75% rate of complete ance with a single treatment session [5-9] (Table
the shock
9 (75)
perforation)
debris
fragmentation during
The number
did not have a direct
the
in initial
of pulses relationship
to stone size. One 1 -cm-diameter intrahepatic stone fragmented completely with seven pulses, whereas a 1 .5-cmdiameter stone in the common bile duct required 368 pulses to be cleaved into fragments. Nishioka et al. [1] have shown that cholesterol calculi require more energy for fragmentation
than pigment stones do, but we did not analyze these patients’ stone debris for chemical composition. None of our patients suffered significant immediate postprocedural morbidity. Transient hyperamylasemia developed in two patients without clinical sequela. In one of these patients, prolonged combined endoscopic and radiologic manipulations were made more difficult by the presence of pancreas divisum. One patient had Pseudomonas sepsis and duodenal erosion 30 days after Iithotripsy and endoscopic stent placement. The acute illness responded promptly to removal of the stent and stone fragments and IV antibiotics. In one patient, the stone could not be immobilized against the duct wall adequately to allow fiber contact without a
cooperative
effort.
By using
a catheter
placed
through
an
existing T-tube track, saline was forcefully injected onto the stone from above, displacing the stone onto the laser fiber, which had been introduced endoscopically, allowing fragmentation to occur. The cooperation of endoscopists and radiol-
ogists working as a team was crucial to success in this case. Laser lithotripsy of large stones retained in the hepatic ducts and common bile duct expands the available nonoperative techniques for treating selected patients in whom other traditional therapies have failed. This technique can be successfully performed with an acceptable complication rate by using either radiologic or endoscopic techniques alone or with a combination of both technologies in a team approach. REFERENCES i
.
Nishioka NS, Levins PC, Murray tation of biliary calculi with
SC, Parrish JA, Anderson AR. Fragmentunable dye lasers. Gastroenterology
1987;93:250-255 2. Burhenne HJ, Fache JS, Gibney AG, Rowley VA, Becker CD. Biliary lithotripsy by extracorporeal shock waves: integral part of nonsurgical intervention. AJR 1988;150: i 279-i 283 3. Staritz M, Rambow A, Grosse A, et al. Electromagnetically generated extracorporeal shock waves for fragmentation of extra- and intrahepatic bile duct stones: indications, success and problems during a 1 5 months clinical experience. Gut 1990;3i :222-225 4. Fried LA, Le Brun GP, Norman RW, et al. Extracorporeal shock wave lithotripsy in the management of bile duct stones. AJR i988;i 51 :923-926 5. Feldman AK, Freeny PC, Kozarek RA. Pancreatic and biliary calculi: percutaneous treatment with tunable dye laser lithotripsy. Radiology 1990;i 74:793-795 6. Berci G, Hamlin JA, Dayhovsky L, Paz-Partlow M. Common bile duct laser lithotnpsy. Gastrointest Endosc 1990;36: 137-i 38 7. Cotton PB, Kozarek RA, Schapiro RH, et al. Endoscopic laser lithotripsy of large bile duct stones. Gastroenterology 1990;99: i i28-i 133 8. Sullivan KL, Bagley DH, Gordon SJ, et al. Transhepatic laser lithotripsy of choledocholithiasis: initial clinical experience. J Vasc Intervent Radiol 1991;2:387-39i 9. Ponchon T, Gagnon P. Valette PJ. Henry L, Chavaillon A, Theiulin F. Pulsed dye laser lithotripsy of bile duct stones. Gastroenterology 1991;iOO: 1 730-i 736
1007
Treatment of Bile Duct Stones Laser Lithotripsy: Results in 12
by
Patients
Steven
We used a pulsed tunable dye laser(operating
L. Dawson1
Peter
R. Mueller1
Michael J. Lee1 Sanjay Saini1 Peter
Norman
Kelsey2
S. Nishioka2
to fragment
large
in 12 patients
(0.8-4.5
after
cm) stones
at 60 mJ per pulse, 504-nm wavelength) in the hepatic ducts or common bile duct to extract stones via a T-tube or endo-
retained
cholecystectomy.
Attempts
scope had been unsuccessful were successfully eliminated occurred
but
developed
in all patients. In nine of 12 patients, all stone fragments during the initial treatment. In one patient, fragmentation remained, requiring endoscopic stenting. Pseudomonas sepsis
debris
in this
patient
30 days
after
the
procedure
the stone fragments. Fragments remaining sifting by using saline flushing or endoscopic of
12
patients,
the
treatment
was
and
was
after lithotripsy or percutaneous
unsuccessful
treated
by extraction
of
were cleared at the same basket extraction. In two
because
of
laser
malfunction.
The
treatment was performed without complications, except for clinically insignificant hyperamylasemia, which occurred in two patients. Our experience suggests that laser lithotnpsy offers a safe alternative for nonsurgical treatment of large retained biliary stones for patients in whom traditional treatments have failed. AJR
158:1007-1009,
Traditional percutaneous
May
1992
therapy for stones retained in the common bile or endoscopic basket extraction. Newer techniques
corporeal
shock-wave
methods
fail or cannot
lithotripsy
(ESWL) or electrohydraulic
be performed,
surgical
duct has been include extra-
lithotnipsy.
reexploration
When these
of the duct
has been
necessary. Recently, tunable dye lasers have become available to fragment stones in the urinary tract and the common bile duct [1]. We present the results of fragmentation of stones retained in the intrahepatic duct or common bile duct by use of laser lithotripsy via T-tube tracks or endoscopic methods in 12 patients in whom standard percutaneous or endoscopic basket extraction was unsuccessful.
Subjects
and Methods
Laser lithotripsy removal Received August 5, i99i sion December 23, 1991.
; accepted
after
revi-
eral Hospital, Harvard Medical School, 32 Fruit St., Boston, MA 02114. Address reprint requests to S. L. Dawson. 2 Department setts
General
and
one
of Gastroenterology, Harvard
Boston, MA 02114. 0361 -803X/92/1 585-i 007 © American Roentgen Ray Society
MassachuMedical
School,
was
fluoroscopic sedation
stones
by the hospital’s an
outpatient.
guidance. with
of cholangitis gentamicin.
Hospital,
biliany
in 12 patients in whom percutaneous was
unsuccessful.
Six
women
or endoscopic
and
One patient
midazolam was Routine
institutional The
and
was
had epidural
sublimaze.
board. done
anesthesia,
Antibiotics
present.
When
necessary,
liver
function
tests
were
IV antibiotics and
measurements
4.5
cm
in diameter.
One
after the procedure.
Patients
patient
stones;
Eleven
in the
patients
radiology given
were of
given, serum
between
were
inpatients
department
but all others not
men
under
were treated
unless
clinical
typically amylase
by IV
evidence
ampicillin levels
and were
had one to three stones, from 0.8 to two patients had intrahepatic stones. T-tube tracks were used for access in seven patients, endoscopy in five. A tunable dye laser (60 mJ per pulse, 504-nm wavelength, 1 Hz, 3-sec pulse length; Candela Laser Corporation, Wayland, MA) was used to fragment the stones. The laser pulses performed
on all patients
review
procedure
basket 52 The laser treatment
six
and 89 years old were included in the study after giving informed consent. was approved
Presented at the annual meeting of the American Roentgen Ray Society, Boston, MA, May 1991. I Department of Radiology, Massachusetts Gen-
was performed
of retained
had
calcified
1008
DAWSON
ET
AL.
AJA:158,
May 1992
Fig. 1.-Use of choledochoscope for direct visualization during fragmentation of a stone in distal common bile duct. A, Cholangiogram obtained via safety cathe-
Downloaded from www.ajronline.org by 186.182.130.56 on 11/02/15 from IP address 186.182.130.56. Copyright ARRS. For personal use only; all rights reserved
ter shows relationship
of stone to choledocho-
scope before laser fiber is introduced. B, Cholangiogram shows laser fiber (arrow) extending beyond tip of choledochoscope to contact stone.
were stone. seven An
conducted by a 0.4-mm-diameter quartz fiber passed to the The number of pulses used to fragment the stones varied from to 420. 8.5-French ACMI choledochoscope (American Cystoscope
Manufacturers
Inc.,
Boston,
MA)
was
inserted
through
the
T-tube
track to visualize the stone in seven patients (Fig. 1). A double endoscope system (1 6-mm-diameter “mother” scope with “daughter” endoscope
placed
through
5.5-mm
was used in all five endoscopy tomies
to
patients,
allow
stones
stone basket. tioned
or
of
the
the
wall
of
remaining flushed
from
channel
“daughter”
In two
intrahepatic,
the stone was posicommon
fiber contact
after lithotripsy
were extracted
the
injections
duct
scope)
had papillo-
endoscope.
eight patients,
the
of mother
These patients
with the fiber by using a modified
bile duct to allow consistent
Fragments kets
placement
were held in contact
In the remaining
against
common
working
patients.
with
of
hepatic,
on
with the stone. with stone
saline
or
bas-
contrast
material. After lithotripsy, the ducts were temporarily drained with a T-tube or nasobiliary tube until follow-up cholangiography showed no residual debris. In five patients who were treated with endoscopy,
fluoroscopic
guidance
for laser placement
was confirmed
with direct
vision as well as
Stones
were successfully
subsequent
basket
fragmented extraction
in 10 patients,
of all fragments
per-
in eight
patients, or saline flushing of all fragments into the duodenum in one patient. In nine patients, the duct was free of stone debris
at the conclusion
tients, mechanical cessful Iithotnpsy; was
attempted.
of the initial
procedure.
In two
pa-
failure of the laser system precluded sucprocedures were aborted before lithotripsy One of these
patients
subsequently
went laparotomy and exploration of the common and multiple stones were removed.
under-
bile duct,
In one patient, several stone fragments remained lithotripsy and could not be removed with endoscopic kets. An 1 1 .5-French Amsterdam stent was placed
after basendoscopically. One month later, the patient returned with Pseudomonas sepsis and duodenal erosion by the stent. The stent
was endoscopically were
basketed
368
pulses.
without
removed, further
No attempts
were
made
to characterize
peak postprocedural amylase level was 1 987 units (normal, 43-1 1 5 units). One patient who underwent lithotripsy (via T-
tube track) of three stones peak postprocedural
Two
patients
amylase
had stones
patients were treated at the initial treatment
from 1 to 2 cm in diameter
had a
level of 503 units.
in the intrahepatic
successfully session.
with
ducts:
removal
both
of all debris
Discussion
Stones retained in the common bile duct are a common problem in biliary surgery. When these stones are less than 1 cm in diameter,
Results mitting
quired
fragments for stone composition. Clinically insignificant hyperamylasemia developed in two patients after lithotripsy. In one patient who had pancreas divisum and an 8-mm intrahepatic duct stone and in whom both radiologic and endoscopic approaches were used, the
was used, and positioning
was verified by correlating the intraprocedural cholangiogram with the fluoroscopic image. Laser lithotnipsy was then performed under direct vision using a “mother-daughter” endoscope configuration.
Stone disintegration cholangiography.
Stone size did not correlate with the number of pulses necessary for fragmentation: one 1 -cm stone required seven pulses, whereas a similar-sized stone in another patient re-
and all remaining complication.
fragments
they can often
be extracted
through
T-tube
tracks by using steerable catheters. If no T-tube is present when the stone is found, endoscopic papillotomy with basket or balloon extraction can be performed. These two techniques should be successful in approximately 90% of patients who have small stones. Dissolution with agents such as methyl tert-butyl ESWL
ether (MTBE) is not an option for intraductal stones. has been used to treat stones in the common bile
duct [2-4] and was available in our institution during the time laser lithotripsy was studied. Although the actual lithotripsy session is noninvasive, patients require a papillotomy for passage of stone fragments, and, if fluoroscopy is used for localization, a nasobiliary catheter or percutaneous tube must be used to opacify the system. These supplementary proce-
dures make ESWL more invasive than it appears to be. Also, targeting of stones is very difficult if sonography is used for localization. With water path, rather than water bath, ESWL, the requirement for anesthesia is lessened, but IV sedation and analgesia is still necessary. ESWL also frequently requires several sessions until patients are free of stones, whereas
LASER
AJA:i58,
May 1992
TABLE
1: Comparison
Downloaded from www.ajronline.org by 186.182.130.56 on 11/02/15 from IP address 186.182.130.56. Copyright ARRS. For personal use only; all rights reserved
Study
of Published
Studies
Total No.
No. (%)
of Patients
Fragmented
LITHOTRIPSY
on Laser
OF
BILE
DUCT
STONES
1009
Lithotripsy
N 0. (%) Completely Cleared
No. (%) with
Immediate
Single-Session Success
Complications
Subsequent
Subsequent
Surgery
ESWL
Cotton et al. [7]
25
23 (92)
20 (80)
12 (48)
1 (bleeding)
3
2
Ponchon
25
22 (88)
22 (88)
1 1 (44)
3 (bacteremia)
2
1
1
0
et al. [9]
1 (duct
Present study
12
Note.-ESWL
10 (83)
cx tracorporeal
=
sh ock-wave
9 (75)
ESWL,
wave
there
travels
across
is a risk of injury
intervening
to those
stone clear1). Because
organs
organs,
during
a factor
that
is not of concern during intracorporeal lithotripsy with pulsed dye lasers. Pulsed dye laser lithotripsy offers a new nonsurgical option for patients in whom these other methods have failed, are unavailable, or are inappropriate. When a stone is struck by a laser pulse, the very high energy
density
surface,
rapidly
causing
raises
ionization
tion of a plasma
state
the temperature
of the stone
of atoms and inducing
above
the stone
surface.
the forma-
As the plasma
expands, an acoustic wave is formed that fragments the stone. Thus, for most effective fragmentation, the tip should be on or very close
to the surface
of the stone.
With endoscopic or radiologic methods, stones in the intrahepatic and common bile duct can be localized, immobilized, and fragmented by using pulses of laser energy transmitted to the stone surface by optical fibers [1 5-9]. The laser fiber itself measures only 0.2 mm in diameter, while the fiber plus covering measures 0.4 mm in diameter. It is easily placed ,
through
a small
sheath
2- to 4-French
many cases fluoroscopy ing the
fiber,
in this
in size.
alone might be suitable series,
direct
visualization
Although
in
for monitorthrough
a
choledochoscope or endoscope was used. The method allows fracturing of large stones into fragments small enough to permit
subsequent
nonoperative
removal,
but whether
the
stones were approached through the T-tube track or endoscopically, secondary maneuvers were required to remove the stone fragments: the stones approached through the Ttube track were either and stones approached
basketed or flushed out endoscopically required
of the duct, papillotomy
and either basket extraction or balloon expulsion into the duodenum. Earlier endoscopic or radiologic attempts at stone removal had failed in our patients because of the size of the retained stones. ESWL was not attempted in these patients. The smallest stone fragmented in this series was 0.8 cm in diameter,
and the largest
green tunable 1 0 patients
session necessary
was
4.5 cm. The use of the coumarin
dye laser allowed and
removal
successful
of stone
in nine of the 1 2 patients. for fragmentation
2 (hyperamylasemia)
lithotripsy.
laser lithotripsy has a 45-75% rate of complete ance with a single treatment session [5-9] (Table
the shock
9 (75)
perforation)
debris
fragmentation during
The number
did not have a direct
the
in initial
of pulses relationship
to stone size. One 1 -cm-diameter intrahepatic stone fragmented completely with seven pulses, whereas a 1 .5-cmdiameter stone in the common bile duct required 368 pulses to be cleaved into fragments. Nishioka et al. [1] have shown that cholesterol calculi require more energy for fragmentation
than pigment stones do, but we did not analyze these patients’ stone debris for chemical composition. None of our patients suffered significant immediate postprocedural morbidity. Transient hyperamylasemia developed in two patients without clinical sequela. In one of these patients, prolonged combined endoscopic and radiologic manipulations were made more difficult by the presence of pancreas divisum. One patient had Pseudomonas sepsis and duodenal erosion 30 days after Iithotripsy and endoscopic stent placement. The acute illness responded promptly to removal of the stent and stone fragments and IV antibiotics. In one patient, the stone could not be immobilized against the duct wall adequately to allow fiber contact without a
cooperative
effort.
By using
a catheter
placed
through
an
existing T-tube track, saline was forcefully injected onto the stone from above, displacing the stone onto the laser fiber, which had been introduced endoscopically, allowing fragmentation to occur. The cooperation of endoscopists and radiol-
ogists working as a team was crucial to success in this case. Laser lithotripsy of large stones retained in the hepatic ducts and common bile duct expands the available nonoperative techniques for treating selected patients in whom other traditional therapies have failed. This technique can be successfully performed with an acceptable complication rate by using either radiologic or endoscopic techniques alone or with a combination of both technologies in a team approach. REFERENCES i
.
Nishioka NS, Levins PC, Murray tation of biliary calculi with
SC, Parrish JA, Anderson AR. Fragmentunable dye lasers. Gastroenterology
1987;93:250-255 2. Burhenne HJ, Fache JS, Gibney AG, Rowley VA, Becker CD. Biliary lithotripsy by extracorporeal shock waves: integral part of nonsurgical intervention. AJR 1988;150: i 279-i 283 3. Staritz M, Rambow A, Grosse A, et al. Electromagnetically generated extracorporeal shock waves for fragmentation of extra- and intrahepatic bile duct stones: indications, success and problems during a 1 5 months clinical experience. Gut 1990;3i :222-225 4. Fried LA, Le Brun GP, Norman RW, et al. Extracorporeal shock wave lithotripsy in the management of bile duct stones. AJR i988;i 51 :923-926 5. Feldman AK, Freeny PC, Kozarek RA. Pancreatic and biliary calculi: percutaneous treatment with tunable dye laser lithotripsy. Radiology 1990;i 74:793-795 6. Berci G, Hamlin JA, Dayhovsky L, Paz-Partlow M. Common bile duct laser lithotnpsy. Gastrointest Endosc 1990;36: 137-i 38 7. Cotton PB, Kozarek RA, Schapiro RH, et al. Endoscopic laser lithotripsy of large bile duct stones. Gastroenterology 1990;99: i i28-i 133 8. Sullivan KL, Bagley DH, Gordon SJ, et al. Transhepatic laser lithotripsy of choledocholithiasis: initial clinical experience. J Vasc Intervent Radiol 1991;2:387-39i 9. Ponchon T, Gagnon P. Valette PJ. Henry L, Chavaillon A, Theiulin F. Pulsed dye laser lithotripsy of bile duct stones. Gastroenterology 1991;iOO: 1 730-i 736
