Choledochoscopic Electrohydraulic Lithotripsy and
Lithotomy for Stones in the Common Bile Duct,
Intrahepatic Ducts, and Gallbladder
HIDEO YOSHIMOTO, M.D., SEIYO IKEDA, M.D., MASAO TANAKA, M.D., SHINJI MATSUMOTO, M.D.,
and YUJI KURODA, M.D.
Choledochoscopic lithotomy with the aid of electrohydraulic From the Departments of Surgery I, Fukuoka University
lithotripsy was performed in 40 patients, including 16 patients School of Medicine, and Kyushu University Faculty of
with choledocholithiasis, 15 with hepatolithiasis, and 9 with Medicine, Fukuoka, Japan
cholecystolithiasis. As a route for the choledochoscopy, a T-tube
tract, external cholecystostomy, or jejunal limb of hepaticoje-
junostomy was used in nine patients, while percutaneous trans- addresses the results of application of the EHL technique
hepatic biliary drainage followed by dilatation of the track was
established in 31 patients. The largest cholesterol stone measured in a new series of 40 patients. The present series includes
55 mm by 33 mm and the largest bilirubinate stone measured patients with calculi in the common bile duct, gallbladder,
52 mm by 37 mm. The stones were disintegrated in all but one and the intrahepatic ducts.
patient in whom choledochoscopic access to a gallstone was dif-
ficult due to deformity of the gallbladder. Complete removal of
the stones was achieved in 38 of 39 patients. In a patient with Materials and Methods
hepatolithiasis, small stones located deep in inaccessible Patients
branches of the intrahepatic duct remained unremovable. There
were no serious complications. Minor complications occurred, From June 1985 to June 1988, choledochoscopic elec-
including bleeding from the bile duct mucosa in four patients trohydraulic lithotripsy and lithotomy were performed in
and postprocedure chills and fever in three. Choledochoscopic
lithotomy with electrohydraulic lithotripsy is efficient and useful 40 patients with stones in the common bile duct, intra-
to remove biliary calculi in patients who are poor surgical risks. hepatic ducts, or gallbladder (Table 1). The series included
16 men and 24 women, ranging in age from 45 to 87
A VARIETY OF NONSURGICAL approaches for the years. Eleven patients were between 70 and 80 years of
treatment of cholelithiasis are available. Endo- age and seven patients were older than 80 years. All these
scopic sphincterotomy (EST)"2 and choledo- patients had one or more reasons that rendered nonsur-
choscopic lithotomy3l4 have gained wide acceptance. gical removal of the stones preferable (Table 1).
However huge stones and impacted stones continue to The size of the stone (stones) measured on direct chol-
present a technical problem. Chemical dissolution5'6 and angiograms was greater than 30 mm in diameter in 9
fragmentation of gallstones using extracorporeal shock patients, between 20 mm and 30 mm in 10 patients, and
wave7 are receiving enthusiastic trials but are not always between 7 mm to 20 mm in the remaining 21 patients.
successful. The stone was impacted at the distal common bile duct
Previously we reported the use of electrohydraulic in 12 patients. Twenty-three patients had less than 4
lithotripsy (EHL) under direct visual control during cho- stones, 6 patients had 5 to 10 stones, and 11 patients had
ledochoscopy to remove intrahepatic stones.8 This report numerous stones. Eleven patients had cholesterol stones,
the largest of which measured 55 mm by 30 mm, while
the other 29 patients had pigment stones, the largest of
Correspondences and reprint requests: Hideo Yoshimoto, M.D., De- which measured 52 mm by 37 mm. Computed tomog-
partment of Surgery I, Fukuoka University School of Medicine, 7-45-1, raphy performed in one half of these patients revealed
Nanakuma, Fukuoka 814-01, Japan. distinct calcification of the stones in seven patients.
This study was supported in part by the clinical research fund from
the Fukuoka University Hospital and the Japanese Foundation for Re- Common bile duct stones. Eight of 16 patients with
search and Promotion of Endoscopy. common bile duct stones were high surgical risks; 4 pa-
Accepted for publication: January 19, 1989. tients were older than 80 years, 3 had a history of multiple
576
Vol. 210 * No. S CHOLEDOCHOSCOPIC ELECTROHYDRAULIC LITHOTRIPSY 577
TABLE 1. Indications of Choledochoscopic mon bile duct stones in four patients. Another patient
Electrohydraulic Lithotripsy had hepatolithiasis secondary to stenosis of the common
Number hepatic duct injured at cholecystectomy 15 years before.
of In two patients, the intrahepatic stones were first discov-
Indications Remarks Patients ered by T-tube cholangiography. Four patients had un-
Choledocholithiasis Residual stones with a 5 dergone EST for removal of common bile duct stones
biliary tube in place and one patient had transduodenal sphincteroplasty, but
Extraction failed after EST* 5 the intrahepatic stones were retained.
Difficult duodenoscopic 6
approach Gallbladder stones. Nine patients had stones in the
Hepatolithiasis Polysurgery 4 gallbladder. Two of them presented with jaundice and
Biliary cirrhosis 4 cholangitis due to a so-called confluence stone and had
Retained stones 3 PTBD performed (Fig. 1). Two other patients had an ex-
Advanced age (over 77 years) 2 ternal cholecystostomy for acute cholecystitis; one of them
Previous operation for I
gallbladder cancer had undergone transhepatic drainage of a liver abscess
Detected by chance without I secondary to cholecystitis. The remaining five patients
symptoms had percutaneous transhepatic gallbladder drainage
Cholecystolithiasis Advanced age 4 (PTGBD) to provide a route for lithotomy. All of these
Polysurgery 2 nine patients were poor operative risks (Table 1).
Chronic renal failure I
Congestive heart failure I
Schizophrenia I Instruments
Total 40 An electric surge current generator (Lithotron EL-2 1,
*
EST, endoscopic sphincterotomy. Walz Elektronik Gmbh, Rohrdorf, West Germany) with
a 4.5 French size lithotripsy probe was used. The intensity
of discharge was usually set at 2 with a frequency of 20
abdominal operations, 1 had spinal cord injury, and 1 per second. When the stone was hard, the intensity was
had ischemic heart disease. Twelve of these patients had increased to 3.
undergone cholecystectomy previously, while 4 patients A small-caliber choledochofiberscope (4.8 mm, model
had gallbladders with (1 patient) or without (3 patients) CHF Pl 0, Olympus Optical Co., Tokyo, Japan) was usu-
gallstones. ally used. In cases in which the stones were larger than
Five of the 16 patients had a T-tube (4 patients) or a 25 mm in diameter, a choledochoscope with a larger di-
percutaneous transhepatic biliary drainage (PTBD) tube ameter (6.5 mm, model CHF B3, Olympus Optical Co.,
(1 patient) in place. Five patients had had EST performed Tokyo, Japan) was used, because more rapid infusion of
but duodenoscopic extraction had failed because the saline through its larger biopsy channel permitted us to
stones were huge (larger than 30 mm) in 3 patients, im- keep the endoscopic view clear during the procedure.
pacted and immobile in 1, or located beyond a bile duct
stenosis due to chronic pancreatitis in 1 patient. The duo- Routes for Choledochoscopy
denoscopic approach was considered inadequate for var-
ious reasons in the other six patients. Two of these had Table 2 shows the routes for insertion of the choledo-
the anomalous union of the pancreatic and bile ducts. choscope and lithotripsy instruments. A PTBD tract was
One had undergone Billroth II gastrectomy. The stone used after dilatation in 26 patients, a T-tube tract in 6, a
was impacted at the distal common bile duct in one. The PTGBD tract in 5, and an external cholecystostomy tract
papilla was situated within a diverticulum in one. A huge in 2 patients. In another patient, a blind end of the jejunal
stone (55 by 30 mm) occupied the entire lumen of the limb subcutaneously implanted at previous Roux-en-Y
bile duct in another patient. hepaticojejunostomy was reopened and used as a route
Intrahepatic stones. Fifteen patients had stones in the for choledochoscopy.
intrahepatic ducts. All but one patients with intrahepatic Techniques
stones had a history of one or more biliary operations.
Fourteen of the 15 patients had a reason for the nonop- To establish the percutaneous transhepatic route, the
erative approach for removal of the intrahepatic stones intrahepatic duct or gallbladder was entered under ultra-
(Table 1). An asymptomatic patient in whom the intra- sonic guidance. Using a guide wire technique, a 7.2 French
hepatic stones were detected by echography refused sur- biliary drainage catheter for PTBD or a 10 French Malecot
gical treatment. catheter for PTGBD (Cook, Inc., Markham, Ontario,
Fourteen of these 15 patients were considered to have Canada) was placed in the common bile duct or gallblad-
primary hepatolithiasis, which was associated with com- der, respectively. The catheter tract was dilated twice a
578 YOSHIMOTO AND OTHERS Ann. Surg. * November 1989
FIGS. l A-C. Cholangiograms in a 84-year-old woman with a huge con-
fluence stone. The patient also had diabetes mellitus and cirrhosis of the
liver. (A) Percutaneous transhepatic biliarv drainage under ultrasound
guidance was performed to relieve cholangitis. A stone, about 40 mm
in diameter, occluding the confluence of the cvstic duct and common
bile duct. was visualized. (B) After dilatation of the sinus tract. a cho-
ledochoscope was introduced into the bile duct and an electrohydraulic
lithotripsy probe was advanced through the catheter channel. The probe
was approximated closely to the stone under direct visual control. (C)
The stone was broken into several fragments after application of discharge
sparks.
week by replacing the catheter with a larger one by 2 Choledochoscopy was first attempted 3 weeks after
French size. A 16 to 20 French (5.3 to 6.7 mm) sinus operative or percutaneous biliary catheterization. The
tract was obtained within 2 weeks. drainage catheter was removed, leaving a guide wire in
VOl. 210 . NO. 5 CHOLEDOCHOSCOPIC ELECTROHYDRAULIC LITHOTRIPSY 579
TABLE 2. Routes for Choledochoscopic Electrohydraulic Lithotripsy figures differed among three groups of patients, the small-
Number
est figures were in patients with common bile duct stones
of and largest were in patients with intrahepatic stones (Ta-
Indications Routes Patients ble 4).
Intrahepatic stones PTBD tract* 13
In three of nine patients with gallbladder stones the
T-tube tract 3 fragments moved from the gallbladder to the common
Common duct stones PTBD tract 11
bile duct. The fragments further passed spontaneously into
T-tube tract 3 the duodenum in one patient within 1 week, but the frag-
Jejunal limb of 1 ments remained in the common bile duct for 2 weeks in
hepaticojejunostomy two other patients, necessitating EST for removal of the
Gallbladder stones PTGBD tractt 5 fragments (Fig. 3). In one of the remaining six patients,
External cholecystostomy 2 the fragments stayed in the cystic duct. Because tortuosity
PTBD tract 2
of the cystic duct prohibited basket extraction of these
* PTBD, percutaneous transhepatic biliary drainage. fragments, irrigation with 500 mL of saline through the
t PTGBD, percutaneous transhepatic gallbladder drainage. PTGBD catheter was used for five days after EST, resulting
in clearance of the fragments.
the biliary tract. The choledochoscope was then intro- A firm sinus track formed within 3 weeks in 38 patients.
duced into the biliary tract over the guide wire placed in Maturation ofthe track took 2 months in one ofthe other
the catheter channel. When the sinus tract proved im- two patients because of hepatic congestion secondary to
mature, further attempts for lithotomy were postponed chronic heart failure, and 1.5 months in the other patient,
for 1 week. Once maturation of the track was confirmed, in whom a silicon catheter of the Malecot type was used
the biliary tract was entered under direct visual control for maintenance of the sinus track because deep cannu-
without the aid of the guide wire. After a gallstone was lation into the intrahepatic duct was prevented by the
visualized, the lithotripsy probe was passed through the stones occupying the whole lumen.
catheter channel, the tip was kept in the close proximity The procedure was well tolerated by all the patients
of the stone, and the discharge sparks were applied to the and caused no serious adverse effects. Minor bleeding from
stone under direct vision. After the stone was disinte- the mucosa of the bile duct occurred in four patients. In
grated, a large fragment of the stone was grasped in a three of them, bleeding caused by scratching of the bile
basket catheter and pulled out along with the choledo- duct wall with the tip of the lithotripsy probe stopped
choscope through the sinus tract. This procedure was re- spontaneously. Bleeding in another patient occurred when
peated to remove as many large fragments as possible. a stone packed in the left hepatic duct was fragmented by
Small fragments were removed by irrigation and suction the right intercostal approach. The bleeding was controlled
through the choledochoscope. The lithotripsy was per- by compression with an 18 French catheter advanced into
formed once or twice a week, each session being limited that duct over the guidewire under fluoroscopic control.
to one hour. Three patients had transient chills and fever after the pro-
cedure; this was probably due to cholangiovenous reflux
Results caused by increased biliary pressure during saline infusion
In all but one of the 40 patients the stones were dis- into the bile duct.
integrated into sludge or fragments measuring 5 mm or During the application of spark discharge the endo-
less in diameter, yielding the overall success rate of 97% scopic view was often blurred by dispersion of small frag-
(Table 3). We were unable to fragment a stone impacted ments and bubbles, particularly when the small-caliber
in the cystic duct in only one patient because it was un- choledochoscope (CHF PO0) was used because the catheter
reachable by choledochoscopy. Fragmented stones were channel was filled with the 4.5 French probe, which pre-
completely removed in 38 patients using the combined vented irrigation with saline. This kind of difficulty was
technique of basket extraction, irrigation, and suction. In minimal when the larger choledochoscope (CHF B3) was
only one patient with hepatolithiasis, stones remained in used because of the larger catheter channel; however, the
the small branches of the right posterior segmental duct
because this area was difficult to approach through the
PTBD tract established from the left lateral segmental TABLE 3. Results of Choledochoscopic Electrohydraulic Lithotripsy
duct (Fig. 2). Results/Complications Number of Patients
Most cases required multiple sessions of chledochos-
copic lithotripsy and lithotomy. The number of sessions Successful fragmentation 39 (97%)
Complete removal 38 (95%)
per patient was 4.5 ± 2.5 (mean ± SD), ranging from two Incomplete removal I
to ten. The length from the first biliary catheterization Intrabiliary bleeding 4
until completion of lithotomy was 40 ± 12 days. These Chills and fever 3
580 YOSHIMOTO AND OTHERS Ann. Surg. * November 1989
FIGS. 2A-C. Cholangiograms in a 58-year-old woman with
stones in the left intrahepatic duct and common bile duct. The
patient had undergone cholecystectomy with common duct ex-
ploration and endoscopic sphincterotomy 26 and 8 years pre-
viously. respectively. (A) A huge stone. 51 mm by 42 mm. which
filled the left lateral segmental duct, was visualized by chole-
dochoscopy through the PTBD tract. Several stones were present
in the common bile duct. The right posterior segmental duct
was not visualized on this occasion. (B) The intrahepatic stone
was fragmented into numerous small pieces by choledochoscopic
electrohvdraulic lithotripsy. (C) After removal of the stones from
the left hepatic duct and common bile duct bv choledochoscopic
lithotomy. cholangiographv using a balloon catheter revealed
small stones in the branches of the right posterior segmental
duct (arrow). In spite of several attempts through the PTBD
tract at the left lateral segmental duct. this area was inaccessible
by choledochoscopy. resulting in incomplete lithotomy.
sinus track had to be dilated up to 18 French, requiring was damaged by the shock wave in one of the 51 sessions
several more days before choledochoscopy was attempted. of lithotripsy. The damage occurred when a large stone
The objective lens at the tip of the choledochoscope impacted in the left hepatic duct was fragmented through
the right intercostal approach. It was extremely difficult
to keep a sufficient distance between the tip of the cho-
TABLE 4. Number of Choledochoscopic Sessions and Length ledochoscope and the stone.
from Biliary Catheterization to Twenty-seven patients (choledocholithiasis, 12; cho-
Completion of Lithotomy
lecystolithiasis, 9; hepatolithiasis, 6) more than 1 year after
Biliary Catheterization choledochoscopic lithotripsy were followed by telephone
Number of to Completion of
Indications Sessions* Lithotomy (Days)* interview. The follow-up period was up to 36 months with
a mean of 20.8 ± 8.9 months. Twenty-four of these pa-
Common duct stones 3.2 ± 1.2 28 ± 6 tients were asymptomatic and two patients were dead.
Gallbladder stones 5.2 ± 2.9 42 ± 14
Intrahepatic stones 6.0 ± 2.6 50 ± 12 The two death were not related to the lithotripsy proce-
dure. One of the two patients who had hepatolithiasis and
Overall 4.5 ± 2.5 40 ± 12
biliary cirrhosis secondary to bile duct injury at a previous
* Mean ± SD. operation died of hepatic coma and gastrointestinal
Vol. 210 - No. 5 CHOLEDOCHOSCOPIC ELECTROHYDRAULIC LITHOTRIPSY 581
FIGS. 3A-D. Cholangiograms in a 72-year-
old man with large gallstones and chronic
renal failure. (A) Percutaneous transhe-
patic cholecystography showed two stones,
30 mm in diameter, in the gallbladder.
(B) The lithotripsy probe was in place. (C)
The stones were disintegrated into pieces.
(D) Some fragments moved into the com-
mon bile duct after the lithotripsy, neces-
sitating endoscopic sphincterotomy and
basket extraction.
bleeding 7 months after lithotripsy and lithotomy. The Removal of large stones from the biliary tract has been
other patient with obsolete myocardial infarction died of a challenge for percutaneous choledochoscopic lithotomy.
another attack of myocardial infarction 4 months after We previously dilated the PTBD tract up to 26 French
lithotripsy. Only one of the 27 patients was symptomatic size to extract a stone of 8 mm in diameter,9 but the di-
at the follow-up interview. This patient had lithotripsy latation was associated with considerable pain. Although
for the treatment of choledocholithiasis. Computed to- several types of forceps have been devised, forceps lithot-
mography revealed stones in the left intrahepatic duct omy has been time-consuming and not always success-
that were missed at the time of lithotripsy. Echography ful.10 Presence of bile duct stricture may prohibit the ef-
performed regularly as a follow-up study for nine patients ficient use ofthe forceps. YAG laser has been used during
of cholecystolithiasis revealed new formation of debris in choledochoscopy;"I2 however current laser lithotripsy has
the gallbladder in only one patient 10 months after litho- many disadvantages. Lasers do not crush a cholesterol
tripsy. Ursodesoxycholic acid and hymecromone were stone satisfactorily, the equipment is expensive, laser de-
given to this patient for 2 months, which resulted in dis- livery needs a water-supplying system, and a quartz fiber
appearance of the debris. to transmit the laser beam is too fragile to be manipulated
easily through a choledochoscope and too stiff to be used
Discussion in small tortuous bile ducts. Electrohydraulic lithotripsy
is not associated with any of these drawbacks.
As described in this report, the use of electrohydraulic As shown by the number of choledochoscopy sessions
lithotripsy either via the percutaneous transhepatic route and period of time for complete lithotomy, common bile
or through the T-tube track has enabled us to remove duct stones were most easily removed, chiefly because the
stones from the common bile duct, intrahepatic ducts, common bile duct was straight, allowing easy choledo-
and even the gallbladder. Even large immobile stones were choscopic access to the stones, and the number of stones
successfully removed after fragmentation once the stones was small. Most of the patients had all their stones elim-
were localized under direct vision by choledochoscopy. inated in three sessions; 1 for lithotripsy, 1 for extraction
The success or failure did not depend on the nature of of the fragments, and 1 for confirmation of complete
the stones; even hard, calcified cholesterol stones could clearance of the fragments. This method will be quite an
be fragmented. addition to the treatment of common bile duct stones and
582 YOSHIMOTO AND OTHERS Ann. Surg.-November 1989
is the choice in cases of large or impacted stones that are Complications encountered in this series include minor
not removable by EST. bleeding and shivering chills. The bleeding occurred due
Previously we reported usefulness of choledochoscopic to friction of the ductal wall by the sharp edge of the tip
electrohydraulic lithotripsy for the treatment of intrahe- of the lithotripsy probe. Therefore the metal ring at the
patic stones.8 This seems to be the first choice of the treat- probe tip has been refined into smoother shape, leading
ment in patients who are poor surgical risks. Furthermore to a decrease in the incidence of such bleeding. The cho-
choledochoscopic lithotomy before surgery may also be ledochoscopic view was often blurred by blood, dispersed
justified even in patients without any risk factors.13 An fragments, and bubbles. The use of the large-caliber cho-
appropriate operative procedure for the treatment of he- ledochoscope was helpful to keep the view clear due to
patolithiasis should be selected on the basis of anatomical the larger channel for perfusion. However instillation of
location of bile duct stricture often associated with this a large amount of saline into the biliary tract might cause
disease. This can be achieved more accurately after com- undesirable elevation of ductal pressure. In fact, shivering
plete removal of the intrahepatic stones because bile duct chills and fever probably due to cholangiovenous reflux
stricture tends to be improved after removal of the stones. occurred in three of our patients. Development of a cho-
The combination of choledochoscopic lithotomy and ledochoscope with two catheter channels for perfusion
electrohydraulic lithotripsy would allow for quick removal and suction would be mandatory to overcome this
of the stones before the surgical procedure is planned. problem.
Cholecystectomy is a relatively safe method for the
treatment of stones in the gallbladder. However it carries
some risk when the procedure is to be done in high-risk References
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