Endoscopic Mechanical Lithotripsy Research Articles

Endoscopic large balloon dilation versus endoscopic sphincterotomy in patients with choledocholithiasis

We read with interest the article by Feng et al. [1] entitled ‘‘Comparison of endoscopic papillary large balloon dilation and endoscopic sphincterotomy for retrieval of choledocholithiasis: a meta-analysis of randomized controlled trials’’, which discussed the efficacy and safety of endoscopic large balloon dilation (EPLBD) and endoscopic sphincterotomy (EST) for the treatment of choledocholithiasis. The authors tried to do a systematic review and metaanalysis of the ‘‘randomized controlled trials (RCT)’’ from several databases, two of which are actually retrospective studies [2, 3]. EST has been a standard endoscopic treatment for the removal of common bile duct (CBD) stones, but it is inclined to cause pancreatitis, bleeding, and perforation. Recently, EPLBD has been advocated as an alternative to EST for the management of CBD stones, though it may have a higher risk of post-ERCP pancreatitis (PEP). It remains controversial whether EPLBD is comparable to EST with regard to the feasibility and safety for the management of CBD stones, especially large or difficult stones. In this review, the authors demonstrated that EPLBD was equivalent to EST for the removal of large stones. However, among the seven included studies, only one compared EPLBD and EST, and the other six compared endoscopic balloon dilation following EST (ESLBD) and EST, which is another serious issue. The combination of these two kinds of studies is not recommended by the Cochrane handbook, because it will cause unknown biases by combining ‘‘apples’’ with ‘‘oranges’’ [4]. Furthermore, ESLBD is a different endoscopic treatment for choledocholithiasis, which can combine the merits of EPLBD and EST. Therefore, it is inappropriate to draw the conclusion by summarizing the results from studies comparing ESLBD versus EST and EPLBD versus EST. Endoscopic mechanical lithotripsy (EML) will be needed as a remedy when stones fail to be removed, a problem which has been found to be reduced in the EPLBD group. However, the enrolled study by Stefanidis [5] applied EML to all the patients of the EST group but none of the EPLBD group, which will probably increase the overall usage of EML in the EST group. Post-ERCP hemorrhage is another serious complication after sphincterotomy or balloon dilation, the risk of which was found to be lower in the EPLBD group. However, nine patients with uncorrected coagulopathy were enrolled in the study by Garcia-Cano [3] and thus it should be excluded from Feng’s study, or sensitivity analysis should be done to explore whether it was biased and able to be included in the meta-analysis.

Endoscopic papillary balloon dilatation versus endoscopic sphincterotomy in the treatment for choledocholithiasis: A meta‐analysis

Endoscopic papillary balloon dilatation (EPBD) and endoscopic sphincterotomy (EST) are two common nonsurgical treatments endoscopic retrograde cholangiopancreatography (ERCP) for choledocholithiasis. The aim of this study was to compare the efficacy and safety of EPBD and EST in the treatment for choledocholithiasis, confining the analysis to work reported in the last decade. The rate of overall postoperative complications was chosen as the primary outcome, and 10 other outcomes were secondary outcomes. Relative risk (RR) or Peto odds ratio (OR) were computed as the measures of pooled effects. We planned sensitivity analyses a priori for examining the change in robustness of the sensitivity to excluding studies with some inappropriate objects, technique defects or without full-text acquisition. For complete stone removal, EPBD was similar to EST (95% vs. 96%, P = 0.36) and overall postoperative complications (14.0% vs. 11.7%, P = 0.53). The incidence of post-ERCP cholangitis (2.5% vs. 1.8%, P = 0.40), basket impaction (0.9% vs. 0%, P = 0.16) and perforation (0.0% vs. 0.4%, P = 0.17) were equivalent between EPBD and EST. On the other hand, EPBD caused more post-ERCP pancreatitis (PEP) (9.4% vs. 3.3%, P < 0.00001), but less hemorrhage (0.1% vs. 4.2%, P < 0.00001). People undergoing EPBD required more use of endoscopic mechanical lithotripsy (35.0% vs. 26.2%, P = 0.0004). The results of sensitivity analyses showed no substantial change. EPBD is comparable to EST for stone extraction, though it requires more endoscopic mechanical lithotripsy (EML). EPBD may outweigh EST for patients with coagulopathy; however, it may cause more PEP.

Endoscopic Papillary Large Balloon Dilation: Guidelines for Pursuing Zero Mortality

Since endoscopic papillary large balloon dilation (EPLBD) is used to treat benign disease and as a substitute for conventional methods, such as endoscopic sphincterotomy plus endoscopic mechanical lithotripsy, we should aim for zero mortality. This review defines EPLBD and suggests guidelines for its use based on a review of published articles and our large-scale multicenter retrospective review.

Large-balloon dilation of the biliary orifice for the management of basket impaction: a case series of 6 patients

ERCP with endoscopic sphincterotomy (ES) and stone extraction remains the treatment of choice for bile duct stones 1,2 ; 85% to 90% of all CBD stones can be effectively treated by ES and stone extraction by using balloon catheters or baskets. 3 Regarding the latter devices, impaction of a Dormia basket or fracture of the basket’s traction wires during endoscopic mechanical lithotripsy with an entrapped stone in the distal CBD is an uncommon but well-known complication, 4-6 presenting a challenge to most endoscopists. Reported management strategies include the use of a mechanical lithotriptor to capture the impacted basket and crush the stone, extracorporeal shock-wave lithotripsy, endoscopic laser lithotripsy, or other sophisticated methods. 7-12 This case series describes, for the first time, the safe and effective use of large-diameter balloon dilation of the biliary orifice in the management of impacted baskets in the distal CBD.

A case of common bile duct carcinoma associated with calcification in the tumor

A 75-year old female came to our hospital due to upper abdominal pain and fever. Imaging diagnosis including CT-scan demonstrated a calcified mass in the common bile duct and the tentative diagnosis of choledocholithiasis was done. In order to remove the stone, endoscopic mechanical lithotripsy and extracorporeal shock wave lithotripsy were attempted with no effect. Peroralchoangioscopy, carried out to apply ellectrohydraulic lithotripsy to the stone, revealed the mass to be a tumor instead of the stone. Only calcified specimen was obtained by tumor biopsy ; however bile juice cytology showed class V and surgical therapy was selected. Histopathological findings of the resected specimen demonstrated a well differentiated adenocarcinoma of the bile duct, associated with necrosis and calcification in it. We experienced a rare case of the common bile duct carcinoma like as the stone because of associated calcification in the tumor.

Endoscopic Papillary Large Balloon Dilation with Minor Endoscopic Sphincterotomy in the Management of Difficult Bile Duct Stones

Background/Aims: Endoscopic sphincterotomy (ES) followed by extraction using a basket or a retrieval extraction balloon is the procedure that is generally used for the removal of extrahepatic bile duct (EHD) stones. However, for the large EHD stones (more than 15 mm in diameter), major ES is needed to remove the stones and moreover endoscopic mechanical lithotripsy (EML) is usually needed to crush the large stone. These procedures may result in prolonged procedure time, increased complication rates, and repeated procedure for complete removal of stones. Additionally, the patients with periampullary diverticulum (PAD) may have a higher risk of complications such as bleeding or perforation during a major ES. The aim of this study was to investigate the effectiveness and the safety of endoscopic papillary large balloon dilation (EPLBD) with minor ES for the removal of large EHD stones. Methods: 44 patients (20 men, 24 women; mean age 72.0±11.2 years) with large EHD stones were enrolled for this study. Among them, 20 patients had PAD (45.5%). Major papilla was dilated with 10-mm to 15-mm-diameter balloon (CRETM wireguided balloon dilator, Boston Scientific, U.S.A.) after minor ES. The duration of balloon dilation was 30 to 120 seconds. The stones were then retrieved from the bile duct with a conventional basket or a retrieval balloon. When conventional methods with basket or balloon failed to removed the stones, EML was then performed to break the large stone into small fragments. Results: All patients underwent EPLBD with minor ES. The mean diameter of EHD stones was 18.3 mm (range, 10.9-43.9 mm). In 42 patients (95.5%), EHD stones were completely removed by only one session of the procedure. EML was carried out in two patients for impacted stones in distal EHD. Serum amylase or lipase levels were elevated in 17 patients (38.6%) after the procedure. However, mild pancreatitis developed in only 2 patients (4.5%) of them, and was self limiting. Minor bleeding occurred in 3 patients (6.8%), but they were easily controlled by spraying of epinephrine or balloon compression. No procedure related cholangitis, perforation or mortality was observed. Conclusions: EPLBD with minor ES is safe and effective treatment modality for the retrieval of large EHD stones even in the patients with PAD, and EML could be avoided in the majority of these patients using this approach.

EMS Removing Had Caused No Bile Duct Stenosis. Long Term Follow Up About Removal of Bile Duct Stones with An Expandable Metallic Stent

Background: Recently expandable metallic stent (EMS) removing has been becoming little popular. But the long term results after removing EMS have not been published even now. We had published the new method using removable EMS for lithotripsy at 2003(1). This time we would like to show the long term result of EMS removing about our experience. EMS-Lithotripsy method was developed by us but this method could not become popular because we could not develop original stent for removing bile duct stones and the cost of EMS is relatively high. This presentation might give us the opportunity to develop the removable EMS and so we present long term results. Methods: Forty-six patients (18 women, 28 men; median age 68 +/- 10) with bile duct stones underwent ERCP. The median stone size was 11+/-4mm and the number was 3 +/- 3. A EMS was inserted over a guide wire into the major duodenal papilla. Papillary dilation was performed with a metallic stent. Stones were extracted with an 8-wire spiral basket after endoscopic mechanical lithotripsy through expanded EMS. The metallic stent was subsequently removed with a snare. On two cases choledochoscopy was performed to check the bile duct before and after the stent removing. 35 cases could be followed (mean 7.4 +/- 1.0 years). Result: Duct clearance was 44/46(96%). Lithotripsy was performed safely in 3 patients who had undergone partial gastrectomy with a Billroth II anastomosis. Two stent migration was occurred. These failed cases were caused by stent figure. After removing the stent reddening like meshes of stent was seen by choledochoscopy. 2 cases (6%) have occurred stone recurrence for over 5 years. One of them was B-II reconstruction case. We have not recognized the bile duct stenosis after metallic stent removing for over 5 years. Discussion: EMS removing was not so severe damage to the normal bile duct because bile duct stenosis case was none. The reduction of bile duct columnar epithelium by removing was suspected but sever injury to the fibromuscular layer was rare. So we suspect the removable metallic stent for the benign disease (bile duct stenose and formation of route to bile duct) should be developed. If original stent is established as a method of treatment and the shape of the stent is improved, then both the cost of the stent and the risk of migration may gradually decline. This method is not suitable for treatment of most stones. However, once the method is established as safe, it might play a greater role as a safe for diverticulum and bile duct stenosis case. A Minami et al. A new technique for removal of bile duct stones with an expandable metallic stent Gastrointest Endosc 2003;57: 945-948(1)

A Rare Cause of Gastroduodenal Obstruction

Methods: Case Report An 85-year-old female with history of hypertension was admitted to the hospital with a three day history of nausea and vomiting. An abdominal CT was performed and revealed a large calcified mass (Fig. 1) and pneumobilia. A large obstructing duodenal gallstone (Fig. 1) located in the third portion was found on upper endoscopy. Attempts to remove the object endoscopically were unsuccessful. An apparent fistula was found in the duodenal bulb. An enterolithotomy was performed where a 5 cm gallstone was extracted and she did well post-operatively.FigureConclusion: Discussion Bouveret's syndrome is characterized by gastroduodenal obstruction secondary to an impacted duodenal or pyloric channel gallstone via a cholecysto-duodenal or cholecysto-gastric fistula. Clinically patients present with symptoms of obstruction and radiographic studies reveal pneumobilia, cholelithiasis, and a distended stomach. Endoscopic findings include retained food, an impacted stone, and occasionally a fistula which was seen in our patient. Treatment is usually surgery, consisting of an enterolithotomy with or without concomitant cholecystectomy and fistula repair. Recently there have been reports of endoscopic therapy disintegrating gallstones including intracorporal laser lithotripsy, endoscopic mechanical lithotripsy, and electrohydraulic lithotripsy (1). Reference: 1. Gemmel G, Weickert U, Eickhoff A, et al. Successful treatment of gallstone ileus (Bouveret syndrome) by using extracorporal shock wave lithotripsy and plasm coagulation. Gastrointest Endosc 2007;65:173–175.

A Comparative Study of Outcomes Between Endoscopic Papillary Large Balloon Dilatation (EPLBD) and Endoscopic Mechanical Lithotripsy (EML) in Patients with Difficult CBD Stones

A Comparative Study of Outcomes Between Endoscopic Papillary Large Balloon Dilatation (EPLBD) and Endoscopic Mechanical Lithotripsy (EML) in Patients with Difficult CBD Stones

Endoskopische Extraktion von Gallenblasensteinen

Endoscopic extraction of gallbladder stones were performed, as far as we know for the first time, in three patients with combined choledochocystolithiasis. Following endoscopic papillotomy (EPT) and subsequent mechanical lithotripsy of multiple choledochal concrements measuring up to 3 cm the gallbladder stones were successfully extracted with a Dormia basket through the cystic duct. The patients have remained free of complications after the endoscopic intervention.

ENDOSCOPIC PAPILLARY LARGE BALLOON DILATION AFTER ENDOSCOPIC SPHINCTEROTOMY FOR TREATMENT OF LARGE COMMON BILE DUCT STONE

The extraction of large common bile duct (CBD) stones after an endoscopic sphincterotomy is successful in most cases. However, the procedure often requires a prolonged time and repeated trials, therefore, subsequent occurrence of procedure‐related complications are not uncommon. The purpose of the present paper was to investigate the utility of a combined endoscopic papillary large balloon dilation (EPLBD) preceded by a mid‐incision endoscopic sphincterotomy for the removal of large CBD stones. Stone removal was surprisingly effective with EPLBD in patients with large CBD stones. Occurrence of major complication, such as pancreatitis, bleeding, and perforation, was not observed in any patients who were treated with EPLBD. EPLBD also can be safely carried out on patients with anatomic alteration, such as a periampullary diverticulum, and on patients who have undergone a Billroth II operation. EPLBD is a landmark method of removing a large CBD stone, the impact of which is comparable to that of the introduction of endoscopic mechanical lithotripsy. However, further investigation is required to address the applications and potential outcomes of this procedure. Also, procedure guidelines should be established to avoid major complications.

How to predict the outcome of endoscopic mechanical lithotripsy in patients with difficult bile duct stones?

Objective. Endoscopic mechanical lithotripsy is frequently used to overcome the difficulties of removing large bile duct stones endoscopically. The aim of this study was to identify predictors of endoscopic mechanical lithotripsy failure. Material and methods. One hundred and thirty-four patients who underwent mechanical lithotripsy for difficult choledocholithiasis were evaluated retrospectively. Predictive factors of outcome and procedure-related complications were analyzed. The clinical outcomes of subsequent management were also evaluated in cases of unsuccessful endoscopic mechanical lithotripsy. Results. Endoscopic mechanical lithotripsy was successful in 102 patients (76.1%). Stone impaction, size (≥30 mm), and the stone size to bile duct diameter ratio (>1.0) were significant predictors of endoscopic mechanical lithotripsy failure, with estimated odds ratios of 17.83, 4.32 and 5.47, respectively. There was no difference in complication rates between the successful and failed mechanical lithotripsy groups. When mechanical lithotripsy failed, all patients were successfully treated using various modalities, including surgery, without mortality. Conclusions. An impacted stone, stone size (≥30 mm) and stone size to bile duct diameter ratio (>1.0) were predictors of failure of endoscopic mechanical lithotripsy for a difficult bile duct stone. Alternative approaches should be considered in patients with predictors of unsuccessful endoscopic mechanical lithotripsy in order to avoid wasting time and resources.

Successful treatment of gallstone ileus (Bouveret's syndrome) by using extracorporal shock wave lithotripsy and argon plasma coagulation

Bouveret's syndrome is defined as gastric outlet obstruction after the passage of a gallstone from the gallbladder to the duodenum. Previously, only a few case reports were published that recommended effective nonsurgically therapeutic options such as extracorporal shock wave lithotripsy (ESWL), intracorporal laser lithotripsy (ILL), endoscopic mechanical lithotripsy, and electrohydraulic lithotripsy (EHL) for disintegrating impacted gallstones.2-11

Endoscopic Large Balloon Sphincteroplasty Along with Endoscopic Sphincterotomy (ELBS-EST) in Patients with Large Extrahepatic Bile Duct Stones

Background/Aims: After endoscopic sphincterotomy (EST) had developed, the basket stone removal after EST was the classic treatment modality for the extrahepatic bile duct (EHD) stones. However, for the large EHD stones (usually larger than 15 mm in diameter), endoscopic mechanical lithotripsy (EML) had to be used to break the large stones into small fragments. If there were multiple large EHD stones, repeated EML's were performed to remove the EHD stones. However, if the ampulla could be dilated more wider, such large stones could be removed without EML. The aim of this study was to evaluate the effectiveness of the ELBS-EST to remove the large EHD stones. Method: If the size of the stones were larger than 15 mm, the ampulla was dilated with a balloon (CRETM wire-guided balloon dilator, Boston Scientific, U.S.A) along with EST, with a measurement of 18 mm or 20 mm in diameter. The duration of balloon dilatation times was about 1 min. After dilation of the ampulla, EHD stone removal was tried with a basket. If stone removal failed with the basket, EML was then performed to break the large stones into small pieces. After that the small pieces of stones were removed with the basket. Results: 1) ELBS-EST was performed in 40 patients (M:F = 14:26, mean age: 66.2 yrs). 2) The mean diameter of stones were 19.8 ± 4.6 mm (range, 15∼34 mm). The mean number of stones were 2.3 ±1.4 (range, 1∼6). 3) In 34 (85.0%) patients, the EHD stones were removed without EML. The mean size of stones in these patients was 19.2 mm (range, 15∼34 mm). 4) In 6 (15.0%) patients, failure to remove stones with ELBS-EST alone occurred. The mean size of stones in these patients was 23.5 mm (range, 17∼30 mm). In these patients, only one session of EML was performed to remove the stones. 5) In 5 (12.5%) patients had post-procedure complications (3 cases were minor bleeding, 2 cases were pancreatitis). Conclusion: Endoscopic large balloon sphincteroplasty along with EST is a safe and useful alternative technique in patients with large EHD stones. ELBS-EST could reduce the sessions of EML and substitute the role of EML in some portion. However further study with large scale patients would be needed to evaluate the exact usefulness of ELBS-EST.

Large Balloon-Lithotripsy (LB-L) in Patients with Large Extrahepatic Bile Duct Stones

Background/Aims: After endoscopic sphincterotomy (EST) had developed, the basket stone removal after EST was the classical treatment modality for the extrahepatic bile duct (EHD) stones. However, for the large EHD stones (usually larger than 15 mm in diameter), endoscopic mechanical lithotripsy (EML) had to be used to break the large stones into small fragments. If there were multiple large EHD stones, repeated EML's were performed to remove the EHD stones. However, if the ampulla could be dilated so widely, such large stones could be removed without EML. The aim of this study was evaluate the effectiveness of large balloon dilatation of ampulla to remove the large extrahepatic bile duct stones. Method: If the size of the stones were larger than 15 mm, dilate the ampulla with a balloon (CRETM wireguided balloon dilator, Boston Scientific, U.S.A), with a measurement of 18 mm or 20 mm in diameter. the duration of balloon dilatation were 1 min × 3 times (7 patients), 1 min (16 patients), and 30 sec (1 patient). After dilate the ampulla, EHD stone removal was tried with basket. If stone removal failed with the basket, EML was then performed to break the large stone to small pieces. After that the small pieces of stones were removed with the basket. Results: 1) In 24 patients (M:F = 7;17, mean age: 65 yrs), the ampulla was dilated with balloon dilator. 2) The mean diameter of stones were 20.4'6.1 mm. And the mean number of stones were 2.2 (1.6). 3) Among the 24 patients, in 19 patients, the EHD stones were removed without EML after dilated the ampulla without EML. The mean size of stones in these patients was 19.4 mm. 4) In 5 patients, failed to remove stones with ampulla dilatation alone. The mean size of stones in these patients was 28.7 mm. In these patients, EML was performed to remove the stones. 5) In 1 patient, pancreatitis happened after dilated the ampulla with balloon. In this patient, the duration of balloon dilatation was 1 min × 3 times. Bleeding was happened in 1 patient. In this patient, the duration of balloon dilatation was 30 sec. Conclusion: Large balloon-lithotripsy could reduce the sessions of EML and substitute the role of EML in some portion. Therefore, the large balloon-lithotripsy could be an effective treatment modality in patients with large EHD stones.

Endoscopic management of the liver transplant patient

Endoscopic management of the liver transplant patient

A case of common bile duct stones with the complete separated orifices of commen bile duct and main pancreatic duct, successfully treated by endoscopic sphincterotomy (EST)

A 79-year-old male was admitted to our hospital because of upper abdominal pain. He was diagnosed to have acute cholangitis due to choledocholithiasis, according to the results of blood tests, ultrasonography and abdominal CT. Endoscopic examination showed 2 separated papillae which had individual orifices, and a duodenal diverticulum was identified close to the oral side of the papillae. Endoscopic retrograde cholangiopancreatography (ERCP) revealed separated openings of common bile duct (CBD) and main pancreatic duct (MPD) . The opening of CBD was located on the oral side of that of MPD. According to these findings, he was also diagnosed as having the completely separated orifices of CBD and MPD, which could be differentiated from choledochoduodenal fistula. Endoscopic retrograde cholangiography (ERC) revealed several stones, 11 mm maximum in diameter, in the CBD. EST was performed safely, and CBD stones were thoroughly removed by means of endoscopic mechanical lithotripsy (EML) . No complications occurred after the removal of stones by EST and EML. The orifice of CBD separated from that of the pancreatic duct is seldom encountered, and was reported to exist with a frequency of fewer than 4% in Japan. Differentiation of the condition from choledochoduodenal fistula is necessary because the incision range during EST is basically different between these two conditions. The present experience indicates that EST is useful and safe for the treatment of CBD stones in the patients with the complete separated orifices of CBD and MPD, if it is possible to be differentiated from choledochoduodenal fistula and the orifice of CBD is not located inside the diverticulum.

Efficacy and safety of endoscopic papillary balloon dilation for removal of common bile duct stones in the elderly

From May 1996 through August 1998, endoscopic papillary balloon dilation (EPBD) was performed to remove common bile duct stones in 17 elderly patients, aged 75 to 87 (average 81.9), including 7 with juxtapapillary diverticulum. The balloon-tipped biliary catheter for EPBD was inflated at a pressure of 10 atm, for 2 minutes, and the maximum diameter of the inflated balloon reached 8 or 10 mm. After one or two ERCP sessions using EPBD alone, the bile duct stones were removed in 16 (94.1%) of 17 patients, and endoscopic mechanical lithotripsy was required in 6 (35.3%) patients. Another patient required additional sphincterotomy for removal of the stone. Massive bleeding or intestinal perforation, which can be major complications of EPBD, did not occur, and while the minor complication of transient abdominal pain was observed in 3 patients but there was no case of pancreatitis. The clearance rates of stones and complication rates in our EPBD procedure were similar to other reports and to those of our data in younger patients, aged under 75. EPBD was a safe and effective technique for the extraction of the common bile duct stones in elderly patients.

Diagnostic and Therapeutic ERCP in Children with Sickle Cell Disease

Over a period of less than 3 years, diagnostic and therapeutic endoscopic retrograde cholangiopancreatography (ERCP) was performed on 24 children with sickle cell disease (SCD) aged 8–18 years. The adult side-viewing duodenoscope was used. Intravenous sedation with diazepam and meperedine was used except in those children 10 years of age and younger, in whom general anesthesia was used. The indications for ERCP were obstructive jaundice in 18 patients, pancreatitis in 2, cholangitis in 2, recurrent biliary colic in 1, and postlaparoscopic cholecystectomy (LC) bile leak in 1. Cannulation of the ampulla of Vater was accomplished in all 24 patients (100%). ERCP provided valuable additional information in SCD patients with hepatobiliary and pancreatic diseases. Endoscopic sphincterotomy was successfully performed in 21 patients, 10 of whom had undergone extraction of common bile duct (CBD) stones endoscopically before LC. Nine other patients with CBD dilation and no stones underwent endoscopic sphincterotomy. In two of them, the papilla was enlarged, with an inflamed orifice suggestive of recent stone passage. Two other patients underwent endoscopic sphincterotomy and nasobiliary drainage: for papillary stenosis in one and for temporary relief of obstructive jaundice due to multiple giant CBD stones in the other. One patient underwent endoscopic mechanical lithotripsy of large CBD stones and stone extraction followed by LC. We conclude that ERCP is safe and useful in the diagnosis and treatment of children with SCD and pancreatobiliary disorders. This is especially true in the era of LC.

Endoscopic mechanical lithotripsy of difficult common bile duct stones

Mechanical lithotripsy for the management of difficult common bile duct stones has sometimes yielded conflicting results. A series of 162 consecutive patients who underwent mechanical lithotripsy was evaluated retrospectively and a large number of variables tested for their association with successful outcome. The procedure was safe (morbidity rate 1.8 per cent) and effective (84.0 per cent stone clearance rate). Univariate and multivariate analysis showed that stone size was the only outcome predictor (mean(s.d.) diameter of grasped versus non-grasped stones 21.7 (6.7) versus 28.3(10.4) mm; F = 10.72, 98 d.f., P = 0.002). The cumulative probability of bile duct clearance ranged from over 90 per cent for stones with a diameter less than 10 mm to 68 per cent for those greater than 28 mm in diameter (P < 0.02). Patients at high risk of lithotripsy failure (stone diameter of 28 mm or more) might more wisely undergo surgery or other non-surgical procedures, such as extracorporeal shock-wave lithotripsy or long-term biliary stenting.