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The management of problematic biliary calculi CHIA-SING HO EUGENE Y. YEUNG Stones in the common bile duct (CBD) are found in lO-12% of all patients undergoing cholecystectomy. Whereas only 6% of patients under the age of 50 years have CBD stones, the figure rises to 33% in those over 80 years old. The results of surgical treatment of CBD stones vary according to age and other factors. Surgical mortality for fit patients undergoing surgery for CBD stones is 1% or less, but for those over 60 years old who either have jaundice, cholangitis, stricture or associated medical disease, or are undergoing reoperation, the mortality rises to between 5% and 28% (Johnson and Hosking, 1987). Since the advent of endoscopic sphincterotomy in 1974 (Classen and Demling, 1974; Kawai et al, 1974), the approach to treating CBD calculi has fundamentally changed. The overall success rate of endoscopic sphincterotomy in clearing these stones is 85-90%, and the mortality and morbidity rates are better than those for surgery (Cotton, 1984). Thus, this procedure has replaced surgery as the method of choice for treating biliary calculi, both in the elderly with coexisting medical disease and in the fit patient with a previous cholecystectomy. DEFINITION Problematic biliary calculi are CBD or intrahepatic stones that are not amenable to treatment with endoscopic sphincterotomy and basket manipulations. Patients with these stones usually have one or more of the following: 1.

2.

Inaccessible biliary tree. Retrograde cannulation of the ampulla through the duodenoscope may be difficult after choledochoenterostomy (Figure 1) or Bilroth II partial gastrectomy because of the altered anatomy of the upper gastrointestinal tract, or when the ampulla opens into a duodenal diverticulum. Bile duct stricture. Calculi often form proximally to a bile duct stricture because of stasis. Not infrequently, intrahepatic stones are also formed proximally to anastomotic strictures following choledochojejunostomy. Even with endoscopic papillotomy and retrograde dilation of the stricture, the calculi are often difficult to clear and the long-term efficacy of stricture dilation is dubious.

BailliLre’s Clinical GastroenterologyVol. 6, No. 2, June 1992 ISBN o-7020-1623-3

355 Copyright 0 1992, by Baillikre Tindall All rights of reproduction in any form reserved

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Figure 1. Percutaneous management of biliary calculi after choledochoenterostomy: (a) leftsided percutaneous biliary drainage was performed, showing multiple calculi in the left duct and the common hepatic duct (arrows); (b) final cholangiogram showing clearance of calculi.

3.

Large and impacted stones. Stones over 1.5 cm in diameter are usually considered large and are often difficult to remove endoscopically, particularly when they are impacted. Included in this category are stones trapped within a basket that cannot be extracted from the bile duct (Figure 2). Intrahepatic stones can be diffuse (more than four branches) or localized, and may or may not be associated with strictures in the intrahepatic ducts. Endoscopic sphincterotomy alone seldom clears these calculi, and because they are remote from the ampulla, basket manipulation to entrap the stone is often difficult.

RADIOLOGIC

INTERVENTIONS

In the last 15 years, significant advances have been made in interventional radiology. Percutaneous biliary drainage (PBD) introduced initially for decompression of benign and malignant biliary obstruction (Molnar and Stockum, 1974; Ring et al, 1978) has become an established method for percutaneous access to the biliary tree. Following percutaneous drainage, various biliary interventions can be performed: transcatheter biopsy (Elyaderani and Gabriele, 1980; Cropper and Gold, 1983); cholangioscopy (Nimura et al, 1981); dilation of strictures (Molnar and Stockum, 1978; Salomonowitz et al, 1984); contact dissolution and removal of stones (Motion, 1981; Brandon et al, 1988); insertion of endoprostheses (Burcharth, 1978; Lammer and Neumayer, 1986) and internal iridium wire irradiation (Meyers and Jones, 1988). These procedures have made major contributions to the diagnosis and treatment of biliary diseases. This chapter

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focuses on the radiologic management of patients with problematic calculi, emphasizing techniques, results and complications.

biliary

METHODS Transduodenal

endoscopic management

Various endoscopic devices, including mechanical (Riemann et al, 1982; Schneider et al, 1988), laser (Kozarek et al, 1988) and electrohydraulic

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Figure 2. A large intrahepatic stone with trapped endoscopic basket treated with percutaneous transhepatic interventions: (a) percutaneous transhepatic cholangiography (FTC) shows the trapped basket (arrow) engaging a large intrahepatic stone in the right main duct; (b) percutaneous transhepatic biliary drainage is established-the track leads directly to the stone: (c) percutaneous choledochoscopy with ISWL has broken up the stone and allowed removal of the basket; (d) cholangiogram through an 18-FG catheter showing complete clearance of the bile ducts.

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shock wave (Koch et al, 1980; Leung and Chung, 1989) lithotripsy have been used for transduodenal removal of problematic biliary calculi. When these techniques are unsuccessful, chemical dissolution of stones or drainage with an endoprosthesis (Figure 3) has been performed to avoid surgery (Siegel and Yatto, 1984; Norback, 1989). Endoprosthesis insertion is usually reserved for elderly patients too ill for surgery. Radiologic techniques Radiologic interventions may be grouped according to the following objectives: percutaneous access to the bile duct, disintegration of the calculi and clearance of the stone fragments.

Access to the bile duct Elective percutaneous biliary drainage (PBD). Preparation for PBD includes coagulation screening for prothrombin time, partial thromboplastin time and platelet count. Intravenous access should be established and prophylactic antibiotics given 1 hour before the procedure; the authors routinely give 1 g cephazolin intravenously. The principle of PBD is contrast opacification of the bile duct by skinny needle percutaneous transhepatic cholangiography (PTC) followed by selective cannulation of an appropriate branch duct for drainage. Various techniques for PBD have been well described (Ring et al, 1978; Cope, 1982; Andrews and Hawkins 1984; Yee and Ho, 1990). The main differences between them lie in the size and type of needles and guide wires used for bile duct cannulation . The authors use a small needle and guide wire for cannulation, a technique conceptually similar to that described by Cope (1982) and Andrews and Hawkins (1984). The skin entry site chosen is 2-3cm anterior to the right midaxillary line and about 2cm superior to the duodenal bulb. The porta hepatis is usually directly medial to this point and can be marked on the skin with the tip of forceps. Fluoroscopy is used to ensure that the selected entry point lies below the costophrenic angle to avoid puncturing the lung. A 23-gauge needle with a 20-gauge Teflon sheath (BectonDickinson, Rutherford, NJ, USA) is used for the initial cholangiogram. The sheathed needle is passed horizontally from the skin towards the porta. The needle is removed and sodium diatrizoate contrast medium (Hypaque 60%) Winthrop, Aurora, Ontario, Canada) is injected slowly through the sheath as it is gradually withdrawn from the porta to the periphery, but not outside the liver capsule. If a bile duct is opacified, bile samples are obtained for Gram stain, culture and sensitivity testing. Sufficient contrast medium is then injected to outline the biliary system without overdistending it. If a bile duct cannot be opacified, further passes are made on the same horizontal plane but in a slightly different cephalocaudal axis. Once a duct is opacified, the sheath is advanced into it over a 0.45mm Mandril guide wire (Cook, Bloomington, Ind, USA) to secure a more stable position.

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When stones are found in the CBD or intrahepatic ducts and percutaneous biliary intervention is decided on, an appropriate bile duct is selected for insertion of the drainage catheter. This duct should either contain or lead’ directly to the calculus. If the sheath already present is in the duct that meets this requirement, the percutaneous track is dilated. Otherwise, the desired bile duct is punctured from the right intercostal approach at the level of the duct; the exact level can be determined by lateral fluoroscopy. Once the selected duct is entered by the sheath, a 0.45mm Mandril guide wire is introduced into the bile duct and the sheath removed. Using the Seldinger technique under fluoroscopy, the percutaneous track is dilated over the guide wire to a 9-FG using serial fascial dilators (Cook, Bloomington, Ind, USA). Finally, a 9-FG Kifa catheter (Elema, Stockholm, Sweden), with a curved tip and two side holes 1 cm from the tapered end is inserted into the duct. With the aid of a l-mm guide wire, attempts are made to pass the catheter beyond the calculus and into the duodenum. If unsuccessful, the catheter is left to external drainage; otherwise, it is replaced with another Kifa catheter with more side holes for external/internal drainage. When performing PBD for stone removal, special considerations should be given to the following: 1.

2.

3.

Planning of the PBD route. Most patients referred for radiologic management of biliary calculi have had endoscopic retrograde cholangiography-pancreatography (ERCP) or ultrasound scan showing the stones and their location. Based on the ERCP findings, the route of percutaneous biliary drainage can be planned to facilitate subsequent stone removal or disintegration. The ideal track should run horizontally with minimal cephalocaudal angulation, to enter the bile duct at least 1 cm proximal to the stone. Alternatively, the biliary system may be entered via a left-sided puncture (the segment III duct, Makuuchi et al, 1980), assisted by real-time ultrasound guidance. This is only possible if the left lobe of the liver extends below the xiphoid sternum and across the midline. Biliary calculi in non-dilated intrahepatic ducts. Elective PBD performed for stone removal may be technically more difficult than for decompression. Many patients with CBD stones have normal-sized intrahepatic ducts and only minimally dilated CBD. In these circumstances, the main common hepatic duct has been punctured just below its bifurcation without significant morbidity. Catheter buckling. In some patients with biliary calculi, it is difficult to puncture the bile duct and even more difficult to introduce a catheter into its lumen; forcefully advancing the catheter often results in buckling and dislodgement. This is probably related to cirrhosis and periductal fibrosis due to longstanding choledocholithiasis. To overcome buckling, a metallic cannula can be coaxially introduced inside the catheter to act as a stiffener.

Access via Roux-en-Y loop.

(Russell et al, 1986; Gibson et al, 1987).

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Intrahepatic stones recurring after biliaryenteric anastomoses require a combined surgical and radiologic approach. The afferent limb of the Roux loop is fixed surgically to the anterior abdominal wall. This provides a convenient and safe route for percutaneous puncture of the small bowel to gain repeated access to the biliary tree whenever necessary. Dilution of truck. Dilation of the PBD track can be safely performed 2-7 days after PBD, except in patients with cholangitis in whom it is delayed until cholangitis has subsided. Before dilation, the patient is heavily sedated with intravenous pethidine (meperidine), promethazine and diazepam injectable emulsion. Using serial fascial dilators, the track is dilated to 1%FG in one session, and an 18-FG peel-away sheath (Cook, Bloomington, Ind, USA) is left in for stone manipulation. The larger track is necessary for passage of large instruments, e.g. the choledochoscope; it also allows a larger (18-FG) drainage catheter to be inserted at the end of the procedure for external drainage of stone fragments and biliary sludge. Disintegration

of calculi

The major obstacle to the successful removal of biliary calculi is most often their large size, sometimes their location and occasionally the degree of stone hardness. To remove a large stone intact through the transhepatic route, a large track is required, which increases the potential for bleeding. It is often simpler to fragment the stone (lithotripsy) before its removal through the transhepatic track or the ampulla. Several techniques are available for lithotripsy, some of which also facilitate the clearance of fragments. Mechanical manipulation. (Figure 4). Successful removal or disintegration is most often achieved using a Dormia basket and this method should be attempted first; even large stones (> 2.0cm) can be treated successfully this way provided there is sufficient ductal space around the stone to operate the basket. Occasionally, a large stone engaged in the basket is exceptionally hard and will neither fragment when the basket is closed nor be disengaged. This predicament of a ‘trapped basket’ can be salvaged by the use of a mechanical lithotriptor, especially designed for transhepatic application or use through a T-tube track (Ho et al, 1987). The mechanical lithotriptor consists of three rigid, stainless steel components: a metallic cannula, a cross-bar and a T-bar. Each has an opening large enough to pass the traction wire and sheath of a Dormia basket. Once the stone is engaged within the basket, the cannula is threaded over the traction wire and sheath and advanced to the stone. The cross-bar is similarly threaded and advanced to contact the cannula. Then the T-bar is threaded and used as a winch to shorten the wire. By manual winding of the traction wire and sheath, the stone is brought close to the tip of the metallic cannula, and it fragments under tension (Figure 4b). Flushing with saline, performed manually or delivered via a pulsed waterjet device (normally used for oral hygiene, e.g. Water Pik, Teledyne, Rexdale, Ontario, Canada), may also be employed. In this way, soft stones

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Figure 4. Use of mechanical lithotriptor in breaking up hard calculus in the bile duct. (a) The three components being applied for mechanical lithotripsy. The metallic cannula (mc) is advanced through the traction wire to the basket. This is followed by the placement of the cross-bar (cb) and finally the T-bar (T). (b) By turning the T-bar, the stone is brought close to the end of the metallic cannula and is broken up (insert). (c) Cholangiography shows a large (1.5 cm x 2.0cm) calculus in the distal common bile duct which had failed to clear with endoscopic sphincterotomy. (d) The stone has been grasped by a Dormia basket and the metallic cannula advanced to the basket for mechanical lithotripsy. (e) Cholangiogram showing successful lithotripsy of the calculus which is divided into two fragments. (f) Final cholangiogram showing complete clearance of all calculi in the bile duct. From Yee and Ho (1990) with permission.

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may be fragmented, and stone fragments or even large stones may be moved from peripheral ducts to a more favourable position (Cesarani et al, 1988). The safety of using a short pulse (0.25 second) high-pressure water jet (700 bar) for fragmenting common bile duct stones has also been evaluated in animal models (Jessen et al, 1982), the clinical application has not been reported. Contact dissolution. Over the years, agents such as the bile salt sodium cholate, mono-octanoin and methyl-tert-butyl ether (MTBE) have been found to be effective in dissolving cholesterol gallstones in vitro. All three solvents have also been used clinically for contact dissolution of CBD stones with varying degrees of success. This treatment is, however, contraindicated in patients with acute cholangitis or pancreatitis. The time required for dissolution is longest for sodium cholate (weeks), less for mono-octanoin (days) and shortest for MTBE (hours); MTBE is 50 times more effective than mono-octanoin in vitro (Allen et al, 1985). For pigment stones, 1% ethylenediaminetetra-acetic acid (EDTA) has been used for dissolution, but the process is slow (30-60 hours in vitro and days in vivo). It acts by binding the calcium from calcium bilirubinate and leaving soluble sodium bilirubinate (Leuschner et al, 1982). Mono-octanoin solution is infused via the percutaneous transhepatic catheter either by gravity or by a pump. A second transhepatic catheter is also placed in the bile duct and advanced into the duodenum. This serves as a conduit for excess mono-octanoin to drain into the duodenum and prevents biliary obstruction during infusion. The infusion rate is adjusted to 5 ml per hour and the infusion pressure is maintained at 20-25 cm H20. Cholangiograms are obtained before treatment and minimally at weekly intervals to monitor the reduction in stone size. When MTBE is used, the solvent must be prevented from draining into the duodenum where absorption by the mucosa may cause nausea, vomiting, somnolence and general anaesthesia, as well as duodenal erosion. A 7-FG balloon catheter (Meditech, Watertown, Mass, USA) is used to occlude the common bile duct distal to the calculi. Repeated infusion and aspiration of 5 ml of MTBE is carried out through a second catheter, which is placed as near to the stone as possible. The procedure is completed by flushing the biliary tree with an injection of 50 ml saline. To determine the nature of bile duct stones, Gandini et al (1988) inserted an 8.5-FG fibrescope (Microvasive-Visicath Application, Milford, Mass, USA) through a percutaneous drainage catheter to determine the colour of the stones. Stones consisting of yellow cholesterol only, and not black bilirubinate, were selected for MTBE dissolution. Choledochoscopy

and intracorporeal

shock wave lithotripsy

(ISWL) .

Electrohydraulic shock wave generated on the same principle as extracorporeal shock wave lithotripsy (ESWL) can be directly delivered via a bipolar coaxial electrode (probe) to the biliary calculus for fragmentation. The shock wave is created following discharge of high-voltage electrical sparks across the electrodes submerged in water or bile. These sparks produce

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high-amplitude hydraulic shock waves that disrupt the crystal matrix of the calculus causing fragmentation. The technique of ISWL was first used to fragment a large bile duct stone through a T-tube track under fluoroscopy in 1975 (Burhenne, 1975). Without direct visual control, however, the electrodes may discharge while in contact with ductal mucosa, causing bleeding or perforation. In view of this, ISWL application under fluoroscopy is limited. Modern flexible fibreoptic endoscopes allow direct visual control of shock wave lithotripsy through either retrograde (Koch et al, 1977; Leung and Chung, 1989) or percutaneous choledochoscopy (Nimura et al, 1981; Chen et al, 1986). The transhepatic approach provides a shorter, more direct route to the calculus than the retrograde approach. A rigid nephroscope can also be used to fragment and remove large intrahepatic stones (Andreoni et al, 1989). Although the rigid scope requires a larger transhepatic track (20-30FG), it has the advantage of allowing the use of either electrohydraulic or ultrasonic lithotripsy and forceps for removal of fragments. The flexible choledochoscope (CHF type 4B, Olympus Optical Co., Tokyo, Japan) is introduced into the bile duct through an 18-FG peel-away sheath using fluoroscopic guidance. Combined visual and fluoroscopic guidance is then employed to locate the stone. The 3-FG coaxial electrode probe is connected to an electric surge current generator (Disintegrator Model SD-l, Northgate Research Corp., Plattsburg, NY, USA) which sets the frequency and voltage of the electrical discharges. After testing, the probe is introduced through the working channel of the choledochoscope and is manipulated to the calculus. Continuous infusion of 0.9% saline through the same channel is needed to clear the endoscopic view which is clouded after each electrical discharge. In general, brief intermittent discharges for 3-4 seconds at a rate of one or two per second at 90-100 kV are sufficient for fragmentation. More discharges are required for very large stones. Laser lithotripsy. The exact mechanism by which laser energy breaks up calculi is not known. One theory is that the laser energy causes the formation of plasma (a gaseous collection of ions and electrons) that can collapse, initiating a mechanical shock wave. Another theory suggests that calculi are fragmented by the thermal effect of laser energy (Nishioka et al, 1987). Several types of lasers have been employed to fragment common bile duct stones, namely continuous neodymium-YAG (Orii et al, 1981), pulsed neodymium-YAG (Lux et al, 1986; El1 et al, 1988) and tunable dye laser (Kozarek et al, 1988). The continuous neodymium-YAG laser may cause significant ductal damage, but the other forms of laser are believed to cause little or no injury to the ductal mucosa. As in ISWL, the laser energy is transmitted through a probe (fibreoptic) to the biliary calculus under direct visual control through the choledochoscope. Ultrasound lithotripsy. At present, ultrasound waves used for lithotripsy are transmitted mainly via a rigid probe used in conjunction with a rigid scope. For biliary lithotripsy, it has been used to remove intrahepatic stones via a relatively straight T-tube or PBD track (Hwang et al, 1986; Andreoni et al,

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1989). The ultrasound waves are harmless to the mucosa and cause no morbidity. The development and use of flexible ultrasound wave guides have been reported with some success. Bean et al (1977) used a flexible transmission probe, made of cobalt-nickel alloy (Elgiloy), to fragment a large, retained CBD stone through a T-tube track. Another prototype was devised and tried by Demling et al (1984), but the sound waves were attenuated and heat was produced at the bends of the flexible scope, limiting its use. Further research and development will be needed before flexible transmission probes can be brought into clinical use. Clearance

After lithotripsy by one or more of the above methods, stone fragments will either pass spontaneously through an endoscopic sphincterotomy or be removed via the sheath using Dormia baskets. In some patients, however, endoscopic sphincterotomy is unavailable because of altered upper gastrointestinal anatomy from previous surgery. In these patients, clearance of stone fragments depends on manipulation through one of the following methods. Transampullary expulsion. This may be achieved using a modified Dormia basket with a 3-cm flexible tip (Clouse, 1983); the stone is grasped and pushed into the duodenum through the ampulla. Alternatively, common duct stones can be pushed into the duodenum after transhepatic balloon dilation of the ampulla of Vater (Berkman et al, 1988). In this technique, the patients are given intravenous narcotic analgesics and sedatives as well as prophylactic antibiotics prior to the procedure. Two catheters are introduced through the transhepatic tract: a balloon dilation catheter to the duodenum and a 5FG angiographic catheter to the common bile duct. The balloon catheter is used to dilate the ampulla to a size slightly larger than the diameter of the largest stone. Sometimes, two balloon catheters are used simultaneously for very large stones. After dilation, the balloon catheter is withdrawn into the bile duct, proximal to the stones; the angiographic catheter is used for contrast injection and to push the stones distally if necessary. The balloon is then reinflated and pushed over a guide wire into the duodenum, thereby clearing the common bile duct of stones. The process is repeated for multiple stones. Removal through Roux-en-Y loop. Intrahepatic

stones located proximally to an anastomotic stricture (choledochoenterostomy) or intrahepatic ductal stricture may be reached through a direct percutaneous puncture of the Roux-en-Y loop as described previously. The stricture is dilated with a Gruntzig balloon (Meranze et al, 1986; Chetty et al, 1990) before attempting to remove the stones by the use of occlusion balloons (Meditech, Watertown, Mass, USA). A curved tip 7-FG biliary manipulation catheter (William Cook: Europe, Copenhagen, Denmark) is used together with a l-mm guide wire to pass beyond (proximal to) the calculi in the intrahepatic

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duct. The manipulation catheter is then replaced by an occlusion balloon catheter over the guide wire. The balloon is inflated to occlude the bile duct and slowly withdrawn, thus sweeping the calculi past the stricture. Percutaneous transhepatic papillotomy. Transhepatic papillotomy (Figure 5) may be performed to improve drainage in patients in whom an endoscopic sphincterotomy is not possible. The technique was first described by Gunther et al (1978) and has since been reported by several authors (Coburn et al, 1986; Burhenne and Scudamore, 1986; Gandini et al, 1990a). In this technique, the endoscopic papillotome is introduced into the CBD through a 9-FG Kifa PBD catheter and the papillotome placed across the sphincter of Oddi. The cutting wire is positioned under fluoroscopy to face laterally, away from the pancreas (Figure 5a). After the papillotome is bowed, a mixture of cutting and coagulation current is passed through it to effect the sphincterotomy. Recently endoscopic control has been added to improve monitoring of the sphincterotomy and may reduce morbidity. Two approaches have been described: retrograde duodenoscopy or percutaneous choledochoscopy. An end-viewing duodenoscope can be inserted to the second part of the duodenum, to ensure the placing of the papillotome at the 11 o’clock position, to determine the size of the sphincterotomy and to identify any bleeding. Alternatively, if a duodenoscope cannot reach the region of the ampulla, a choledochoscope can be inserted transhepatically into the bile duct, and the papillotome inserted through its working channel. Direct visual monitoring of papillotomy from the CBD is thus possible (Mason et al, 1982).

Extracorporeal

shock wave lithotripsy

Shock waves are high-pressure waves characterized by a rapid steep rise (in tens of nanoseconds) followed by an exponential decrease in pressure. In ESWL the shock waves are generated outside the body and are transmitted to the stone through a water bath or water ‘cushion’, provided no bone or air-containing structure impedes their path. When the shock waves meet the stone, compressive and tensile forces build up, which (together with cavitations) cause erosion and disintegration of the stone. Renal stones, gallstones, bile duct and pancreatic stones can be fragmented by shock wave lithotripsy. The degree of stone fragmentation depends on the matrix and crystalline structure of the stone as well as its volume and the quality of its surrounding medium (Delius et al, 1988; Schachler et al, 1988). Various systems for ESWL are available: spark gap discharge technology (Dornier system), piezoelectric elements (Wolf system), electromagnetic system (Siemens system). Lithotriptors used for biliary calculi use a biplanar x-ray system for stone targeting; ultrasound localization is also possible (Benes et al, 1989; Choi et al, 1991). The stones are identified by cholangiography via a nasobiliary tube, a T-tube or a percutaneous transhepatic catheter. Patients undergoing ESWL treatment for bile duct stones should have a previous endoscopic sphincterotomy, normal coagulation parameters, and no aortic aneurysms or lung tissue in the path of the shock wave.

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Figure 5. Percutaneous transhepatic sphincterotomy. (a) Model showing endoscopic papillotome inserted through a PBD catheter and positioned for sphincterotomy. (b) Cholangiogram of a patient with partial gastrectomy, Bilroth II gastroenterostomy and failed endoscopic sphincterotomy. Multiple CBD stones are shown. (c) A generous percutaneous sphincterotomy is created. (d) Cholangiogram showing complete clearance of CBD stones; the arrow shows a CBD stone in the duodenum having been pushed through the papillotomy. From Yee and Ho (1990) with permission.

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The patient lies in the supine position during ESWL treatment; the number of shocks given ranges from a few hundred to a few thousand. More than one session of EWSL may be necessary for complete stone clearance. General anaesthesia may be required depending on the equipment used (e.g. Dornier HM3 lithotriptor), although with newer equipment, heavy sedation or epidural anaesthesia may suffice. RESULTS

AND COMPLICATIONS

Transduodenal

endoscopic management

The results and complications of radiologic management of problematic biliary calculi must be viewed in relation to those for other forms of treatment. In a 1980 survey, Ossenberg and Heueck (1980) found that endoscopic sphincterotomy performed on 3276 patients for CBD stones was 90% successful in clearing stones from the bile duct; the complication rate was 6% and the mortality 1%. Table 1 summarizes the recurrence, mortality and complications from surgical and endoscopic treatment of biliary calculi (Peel, 1990). Table 2 outlines the results of different modalities of transduodenal treatment for large stones. With the endoscopic mechanical lithotriptor, the success rate ranged from 50% to 87% with a complication rate of 3-6%, mostly due to bleeding from endoscopic sphincterotomy. No mortality is Table 1. Summary of recurrence, complications and mortality of CBD stones after surgical and endoscopic treatment.

Mortality Early complications Late recurrent stone/stenosis

Surgery (%I O-8’ 10-46 5-10

Endoscopic sphincterotomy (%I O-l.4 5-10 4-10

* 5-28% patients over 60 years of age. From Peel (1990) with permission. Table 2. Results and complications of various transduodenal methods of management of large CBD stones. Reference Schneider et al, 1988 Riemann, 1985 Leung et al, 1988 Koch et al, 1980 Leung & Chung, 1989 Cotton et al, 1990 Kid et al, 1989

Number 209 84 32 14 5 19 63

Method Mechanical Mechanical Mechanical EDTA Electrohydraulic Electrohydraulic Tunable dye laser Endoprosthesis

* Postoperative mortality following surgery.

Success Complication (%) (%o) 87.6 2.9 82.1 6.0 50 6.3 86 0 100 0 80 5 100 9

Mortality (%o) 0 0 6.0* 0 0 0 0

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reported with the use of the mechanical device. The lower (50%) success rate was associated with recurrent pyogenic cholangitis, a disease prevalent in the Far East (Leung et al, 1988). Experience reported with the use of the newer lithotripsy techniques is much more limited. Koch et al (1980) reported success in treating 12 of 14 patients with large CBD stones using electrohydraulic shock wave through a duodenoscope. No complications were reported. Recently, electrohydraulic shock waves applied with direct visual control through peroral choledochoscopy were successful in treating all 5 patients with large CBD stones (Leung and Chung, 1989) without morbidity. Although laser lithotripsy has been reported to be successful in vitro (Nishioka et al, 1987), its clinical application has been limited. A combined report from three centres constitutes the largest experience to date (Cotton et al, 1990): ductal clearance was achieved in 15 of 19 patients with no morbidity. Laser lithotripsy is limited because it is expensive both to acquire and to maintain, and-more importantly-it is technically difficult to use in a retrograde endoscopic setting (Kozarek et al, 1988; Cotton et al, 1990). When endoscopic manipulations fail to dislodge large CBD stones, insertion of endoprostheses has been successful in relieving biliary symptoms in elderly patients. Although this is reported to be safe by some, Kiil et al (1989) reported immediate complications in 9 of 63 patients including sepsis, haemorrhage or duodenal perforations. Complications during follow-up were mainly cholangitis related to blockage of the endoprosthesis; 12 of the 63 patients required replacement of the device. Radiologic interventions Before considering the overall results and complications of radiologic interventions, the results and complications of each of the procedure components-percutaneous biliary drainage, lithotripsy and clearancemust be reviewed. Percutaneous transhepatic access

The success rate for PBD in patients with dilated intrahepatic bile ducts approaches 98-100% in experienced hands (Nakayama et al, 1984; Ho et al, 1991). Not all patients with CBD stones have dilated intrahepatic ducts, but their CBD are usually sufficiently dilated for successful cannulation. The complications of percutaneous biliary drainage have not been well defined and the reported incidence varies significantly among centres. At least two reasons can be cited for this wide variation. First, as with any technical skill, expertise is important in minimizing morbidity. The expertise in PBD can be evaluated from its success rate in patients with dilated ducts. Success rates below 95%, in general, reflect insufficient experience. The direct linkage between experience and reduced complication rate is confirmed by Riemann (1984) who reported a 500% difference between the most and least experienced centres (see below). Second, complications are significantly affected by the indications for PBD; much lower incidence of

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Table 3. Relationship between diagnosis (malignant and benign disease) and complication rate (morbidity and mortality rate).

Complication

Malignant disease (N= 152) n (%I

Cholangitis Cholangitis with hypotension Tube migration/dislodgement Tube blockage Leaking ascites Pleural effusions Bile peritonitis Major haemorrhage Total major complications Death Overall

Benigh disease

46(30) 5(3) 43(28) 21(14) 7(5)

20) 2(l) l(1) lO(7) 4(3) 85(56)

From Yee and Ho (1987) with permission.

Table 4. Mortality associated with percutaneous transhepatic biliary drainage (n = 2471). Deaths due to minor complications Deaths due to major complications Total deaths

10 25 35

(0.4%) (1.0%) (1.4%)

From Riemann (1984) with permission.

Table 5. Incidence and types of complications following percutaneous transhepatic biliary drainage (n = 2471). Major

Bile leakage/biliary peritonitis Sepsis Haemobilia Haemorrhage RetropetitoneaYsubphrenic abscess Renal failure Total major complications

49 42 41 39 10 2 183

Minor

Catheter displacement Cholangitis (without septicaemia) Hypotension Hyponatraemia Pneumothorax Total minor complications Total From Riemann (1984) with permission.

164 146 33 25 7 375 558

(15.2%) (22.6%)

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morbidity and mortality is found in patients with benign versus malignant disease (Yee and Ho, 1987). In patients with malignant disease, PBD is associated with a 2% procedure-related mortality and an 8% major complication rate compared with 0% and 2% respectively in patients with benign disease (Table 3). In a worldwide survey on the complications of percutaneous transhepatic drainage, Riemann (1984) obtained data on 2471 patients through questionnaires from 18 international centres. He reported overall complications of 22.6% with 7.4% being major complications and 15.2% minor (Tables4 and 5). The mortality related to the procedure was 1.4%, occurring only in patients with malignant obstruction; no death related to the procedure was found in 364 patients with benign disease. Not surprisingly, Riemann also reported that complication rate is linked with experience. The centre with the lowest number of procedures (40) had the highest complication rate (78%), while the most experienced team (450 procedures) had the lowest rate (14%). When PBD is performed to extract biliary stone, the complications are comparable to those noted in endoscopic methods (Tables 1 and 2). For example, Ho et al (1991) reported 2 complications in 65 patients treated for biliary calculi (3.0%). Both patients bled through the PBD track and required blood transfusion. One subsequently underwent laparotomy for catheter removal; the other had track embolization with stainless steel coils (Figure 6). A recent report of successful treatment of portobiliary fistula by

Figure 6. Percutaneous treatment of bleeding complication from the PBD track. Four metal coils are deposited along the PBD track following successful removal of intrahepatic stones: the coils prevent further bleeding and the need for surgical treatment for the complication.

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depositing metallic coils in the PBD track is encouraging as it offers nonoperative treatment of a significant complication in stone removal (Rankin and Vellet, 1991). Stone disintegration The success rate of stone fragmentation using the various modalities is much more difficult to assess when the transhepatic route is used than when the transduodenal route is considered. Stones not fragmented by one form of lithotripsy are often subjected to an alternative method at the same session and thus the efficacy of each method is not clearly defined. Using the mechanical lithotriptor, Ho et al (1987) reported complete clearance of ductal calculi in all of 6 patients with no complications. A single drawback of the mechanical device lies in the inability of the basket to grasp very large and impacted stones. Electrohydraulic shock waves applied intracorporeally via a choledochoscope are capable of breaking up both cholesterol and pigmented biliary calculi. A success rate of 100% has been reported in clearing CBD stones, and a slightly lower rate for intrahepatic stones because they may be located in inaccessible sites (MO et al, 1988; Picus et al, 1989; Yoshimoto et al, 1989; Chen and Jan, 1990; Wakayama et al, 1990; Ho, 1991). No major complications have been reported with the use of intracorporeal shock wave therapy. Minor complications have included fever, chills and haemobilia which responded to conservative treatment without surgery. Orii et al (1981) and Zhang (1985) reported successful application of the neodymiumYAG laser in fragmenting large common duct and intrahepatic stones where transduodenal sphincterotomy had failed. In one patient, a superficial ulcer of the common bile duct was observed on choledochoscopy 1 week after laser lithotripsy, but the patient suffered no symptoms. A tunable dye laser has also been applied using the transhepatic or T-tube route in 6 patients without complications (Cotton et al, 1990). Contact dissolution of CBD stones by infusion with sodium cholate takes days to weeks and has a success rate of 65-70%. Pitt and Cameron (1979) reported complications such as elevated levels of liver enzymes, fever, cholangitis and pancreatitis in 10% of their patients. Severe side-effects related to biliary epithelial damage may lead to bacteraemia and sepsis, and fatalities have been reported. Today, this solution is no longer used for choledocholitholysis. In a survey of 222 physicians who had used mono-octanoin in 343 patients to treat CBD stones, Palmer and Hofmann (1986) reported an overall success rate of 54% (26% complete and 28% partial success). Patients with partial success had complete ductal clearance after subsequent interventions. Side-effects occurred in 67%) mostly abdominal pain but also nausea, vomiting, diarrhoea and fever from cholangitis. The average time required for infusion to be effective varied from 7.2 days to 14.6 days. Lifethreatening complications occurred in 5%) including haemorrhage from duodenal ulceration, septicaemia, pulmonary oedema and anaphylactoid reaction. No death was reported in this survey, but death from cholangitis

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with mono-octanoin infusion has been reported elsewhere (Stokes and Clouse, 1990). Clinical experience with MTBE mainly comes from its use for gallstone dissolution through percutaneous cholecystostomy (Thistle et al, 1986). Several investigators have used it for bile duct stone dissolution in a small number of patients with varying success. DiPadova et al (1986) found it completely ineffective, whereas Gandini et al (1990b) found it highly successful and achieved complete dissolution of large CBD stones in 12 of 15 patients. This discrepancy in results is probably related to the method of selection+nly cholesterol stones dissolve in MTBE. Endoscopy with a small fibreoptic endoscope appeared to help significantly in distinguishing cholesterol from pigmented stones and improved the success rate (Gandini et al, 1988). The actual ether perfusion time varied greatly, from 20 minutes to 270 minutes; the period was shorter for stones that dissolved completely (mean 25 minutes) and longer for those that dissolved partially (mean 1662 minutes) (Brandon et al, 1988). Side-effects of MTBE included abdominal pain and mild sedation. Adjuvant removal with baskets was required in patients with partially dissolved stones. The odour from MTBE may also be difficult to prevent and the procedure requires close supervision by a physician (Brandon et al, 1988). Clearance

Transampullary expulsion of bile duct stones into the duodenum by means of a modified Dormia basket was successful in 53 out of 57 attempts, a 93% success rate (Stokes and Clouse, 1990). Complications included pancreatitis in two patients; two other patients required surgery, one for removal of impacted stone and the other for gallstone ileus. Pushing the stones into the duodenum following balloon dilation of the ampulla was successful in all 17 patients with no complication (Berkman et al, 1988). Antegrade sphincterotomy was successfully performed in 10 patients or more with one report of severe bleeding which responded to blood transfusion (Mason et al, 1982; Burhenne, 1986; Gandini et al, 1990; Ho et al, 1991). Overall results of percutaneous

management

A review of the results of percutaneous removal of biliary calculi shows that most reports involved patients with problematic stones, many of whom were elderly (mean age greater than 62 years) and poor surgical risks. Table 6 summarizes the results and complications of percutaneous removal of biliary calculi reported in several series. The overall success rate for both intrahepatic and CBD stones is 92-96%; the success rate is significantly higher for CBD (97-100%) than for intrahepatic stones (70-80%) (Berkman et al, 1988; Yoshimoto et al, 1989; Gandini et al, 1990; Ho et al, 1991). The 30-day mortality varied from 0% to 4% with an average of 2.4% in a total of 248 patients. Complications were not uniformly defined and ranged from 0% to 14%.

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Table 6. Summary of the results and complications of percutaneous management of problematic CBD and intrahepatic stones. Reference

Number

Method

Stokes & Clause, 1990

53

Gandini et al, 1990

81

Ho et al, 1991

65

Yoshimoto et al, 1989

26

Basket Ml-BE Basket MTBE ESWL, ISWL Basket ISWL ISWL

Berkman et al, 1988

17

Balloon

Success (%I 93

Complication (%) 12

92

14

95

3

96 100

minor 0

Mortality 6) 4 3

1.5 0 0

ESWL

Extracorporeal shock wave lithotripsy is most useful in breaking up large or impacted bile duct stones; by itself this technique rarely achieves ductal clearance. Thus all patients undergoing ESWL have a prior drainage procedure to clear stone fragments (e.g endoscopic sphincterotomy, or percutaneous transhepatic drainage or T-tube). Without a clearance route, ESWL may lead to serious morbidity as the stone fragments may cause acute pancreatitis or cholangitis from ampullary obstruction. The results of ESWL are summarized in Table 7. In two prospective, uncontrolled multicentre trials, one in Europe and the other in the USA, the overall success rate for ductal clearance was 86% of 113 patients and 74% of 42 patients respectively (Bland et al, 1989; Sauerbruch and Stern, 1989). All patients had endoscopic sphincterotomy prior to ESWL treatment. A second endoscopic sphincterotomy was required in 78% of patients in the European series, and adjuvant non-surgical procedures were employed in 50% of patients in the American trial. A 30-day mortality rate of one patient (in-hospital mortality two patients 1.8%) and a 26% cholangitis rate were reported in the European study. No mortality occurred and complications were observed in only 35.7% of patients during treatment and 9.5% at discharge with the American study. These results show that ESWL is a useful adjuvant for treating problematic bile duct stones. Table 7. Results, complications and mortality in patients treated for bile duct stones with ESWL. Study Sauerbruch & Stem, 1989 Moody et al, 1989 Greiner et al, 1990 Lee et al. 1990

Number 113 56 55 70

Success (%I 86 79 91 83

Complication (%I 26 18 26 7

Mortality (%I 0.9 0 2 0

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Comparison of transduodenal

377

and percutaneous management and ESWL

No controlled, prospective, randomized or retrospective studies are available to investigate the relative efficacy and safety of transduodenal and percutaneous transhepatic methods for treating biliary calculi. Worldwide, the vast experience with transduodenal endoscopic treatment of biliary calculi has established this as the reference standard against which all other treatment modalities must be measured. The transhepatic approach compares favourably with the endoscopic method both in efficacy and mortality, although the complications of stone removal vary significantly from centre to centre. In many centres, they are comparable with those of endoscopic sphincterotomy. Thus, the percutaneous approach should be considered whenever endoscopic sphincterotomy is unsuccessful, whether owing to failure to perform a sphincterotomy or to inability to clear a large stone through transduodenal manipulation via a sphincterotomy. Where available, ESWL offers an attractive, non-invasive adjuvant to either transduodenal or percutaneous treatment. Surgery for biliary calculi should be reserved for healthy patients requiring cholecystectomy or reconstruction of bile duct strictures, or for patients in whom non-surgical treatment has failed. SUMMARY Recent advances in modern medical technology have significantly reduced the number of patients with ‘problematic calculi’. When a patient does present with a difficult bile duct stone, various non-surgical treatment options are now available. In experienced hands, with healthy or high-risk patients, percutaneous treatment is as safe and as efficacious as endoscopy or surgery. Since it does not require general anaesthesia, and patients recover much more quickly than after surgery, the percutaneous approach is preferred when endoscopy fails to achieve ductal clearance. Surgery is indicated for patients with lesions requiring surgical removal or correction, but seldom for removal of biliary calculi alone. REFERENCES Allen MJ, Borody TJ, Bugliosi TF et al (1985) Cholelitholysis using methyl-tertiary-butylether. Gastroenterology 88: 122-125. Andreoni B, Tombolini P, Biffi et al (1989) Percutaneous ultrasonic lithotripsy of intrahepatic gallstones under endoscopic control. Hepatogastroenterology 36: 4mO8. Andrews RC & Hawkins IF (1984) The Hawkins needle-guide system for percutaneous catherization. I. Instrumentation and procedure. American Journal of Roentgenology 142: 1191. Bean, WJ, Davies H & Barnes F (1977) Ultrasonic fragmentation of large residual biliary tract stone. Journal of Clinical Ultrasound 5: 188-190. Benes J, Chmel J, Dufek Vet al (1989) Extracorporeal shock-wave lithotripsy of the common bile duct stone with ultrasound localisation. Journal of Hepatology 9: 95-98. Berkman WA, Bishop AF, Palagallo GL et al (1988 Transhepatic balloon dilation of the distal common bile duct and ampulla of Vater for removal of calculi. Radiology 167: 453-455.

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