Extracorporeal shock wave lithotripsy of pancreatic stones

Current status and future perspectives for endoscopic treatment of local complications in chronic pancreatitis

Chronic pancreatitis is a progressive disease characterized by irregular fibrosis, cellular infiltration, and parenchymal loss within the pancreas. Chronic pancreatitis treatment includes lifestyle modifications based on disease etiology, dietary adjustments appropriate for each stage and condition, drug therapy, endoscopic treatments, and surgical treatments. Although surgical treatments of symptomatic chronic pancreatitis provide good pain relief, endoscopic therapies are recommended as the first-line treatment because they are minimally invasive. In recent years, endoscopic therapy has emerged as an alternative treatment method to surgery for managing local complications in patients with chronic pancreatitis. For pancreatic stone removal, a combination of extracorporeal shock wave lithotripsy and endoscopic extraction is used. For refractory pancreatic duct stones, intracorporeal fragmentation techniques, such as pancreatoscopy-guided electrohydraulic lithotripsy and laser lithotripsy, offer additional options. Interventional endoscopic ultrasound has become the primary treatment modality for pancreatic pseudocysts, except in the absence of disconnected pancreatic duct syndrome. This review focuses on the current status of endoscopic therapies for common local complications of chronic pancreatitis, including updated information in the past few years.

Adverse events of pancreatic extracorporeal shock wave lithotripsy: a literature review

Pancreatic stones are the result of pathophysiologic changes in chronic pancreatitis with an incidence of more than 90%. At present, pancreatic extracorporeal shock wave lithotripsy (P-ESWL) can be used as the first-line treatment for large or complex stones. Although a large number of studies have proven the safety and effectiveness of P-ESWL, we should also pay attention to postoperative adverse events, mainly due to the scattering of shock waves in the conduction pathway. Adverse events can be classified as either complications or transient adverse events according to the severity. Because the anatomic location of organs along the shock wave conducting pathway differs greatly, adverse events after P-ESWL are varied and difficult to predict. This paper outlines the mechanism, definition, classification, management and risk factors for adverse events related to P-ESWL. It also discusses the technique of P-ESWL, indications and contraindications of P-ESWL, and adverse events in special populations.

Oral Litholysis in Patients with Chronic Calcific Pancreatitis Unresponsive to or Ineligible for Extracorporeal Shock Wave Lithotripsy and Endoscopic Therapy

BACKGROUND/AIMS

Our study aimed to evaluate the effect of oral litholysis in patients with chronic calcific pancreatitis (CCP) unresponsive to or ineligible for extracorporeal shock wave lithotripsy (ESWL) and endoscopic therapy.

METHODS

Trimethadione, an antiepileptic agent, was administered orally at a dose of 0.6-0.9 g/day to 15 patients with this condition. Treatment outcome was evaluated by assessment of dissolution of the pancreatic stones on plain X-ray films and computed tomography scans of the upper abdomen. Plasma glucose, hemoglobin A1c, and body mass index (BMI) were also monitored throughout the therapy.

RESULTS

Litholysis was observed in 13 out of 15 patients (86.7%) and was definite in 10 and partial in 3. Six patients had pancreatitis attacks during the therapy; 5 of whom showed definite litholysis and had only 1 mild attack. Of the 11 patients with normal or impaired glucose tolerance at baseline, none developed diabetes mellitus and all showed litholysis. BMI significantly increased in patients whose pancreatic stones dissolved. There was no vital organ impairment by trimethadione.

CONCLUSION

Oral litholysis using trimethadione may represent a noninvasive and effective complementary treatment in patients with CCP unresponsive to or ineligible for ESWL and endoscopic therapy.

Efficacy and safety of extracorporeal shock wave lithotripsy for chronic pancreatitis

INTRODUCTION

There is still uncertainty regarding the efficacy and optimal modalities of extracorporeal shock wave lithotripsy (ESWL) in the treatment of chronic pancreatitis. The aims of the present study were to assess the safety and the efficacy of ESWL, either alone or followed by therapeutic endoscopic retrograde cholangiopancreatography (adjuvant ERCP) and to determine predictive factors of efficacy, in a real-life setting.

PATIENTS AND METHODS

This study included all consecutive patients who underwent an ESWL in a single University Hospital between 2001 and 2012. The indication for ESWL was obstructive stone(s) of the main pancreatic duct resulting in either painful chronic pancreatitis or recurrent acute pancreatitis. Success was defined by resolution of pain, no analgesic treatment, no acute pancreatitis and no surgical treatment for chronic pancreatitis 6 months after the ESWL.

RESULTS

One hundred and forty-six patients were studied; 6/146 (4%) had a complication of ESWL. Among the 132 patients in whom follow-up was completed, 91 (69%) had an adjuvant ERCP. After 6 months of follow-up, 100/132 (76%) patients achieved success. In multivariate analysis, the single significant predictive factor of the success of the ESWL treatment was chronic pain (p = 0.03). Patients who had chronic pain and needed opioid treatment had less chance of success than patients without chronic pain (OR 95%CI 0.31 [0.07-1.14]). We found no difference in the success rates between patients who underwent adjuvant ERCP and those who had ESWL only (p = 0.93).

CONCLUSION

This study shows that the ESWL is a safe and effective treatment for patients with chronic pancreatitis and obstructive stones within the main pancreatic duct. Systematic association with therapeutic ERCP appears to provide no additional benefit and is therefore not recommended.

Success of Extracorporeal Shock Wave Lithotripsy in Chronic Calcific Pancreatitis Management: A Meta-Analysis and Systematic Review

OBJECTIVES

This is a meta-analysis and systematic review to assess the overall utility and safety of Extracorporeal shock wave lithotripsy (ESWL) in chronic calcific pancreatitis. Primary outcomes are pain relief, narcotic usage, ductal clearance, quality of life, and pancreatic exocrine and endocrine function.

METHODS

Studies involving ESWL in chronic calcific pancreatitis with main pancreatic duct stones greater than 5 mm and patients that failed conservative pain management were included. Fixed and random effects models were used to calculate the pooled proportions.

RESULTS

Initial search identified 1471 reference articles, in which 184 articles were selected and reviewed. Data were extracted from 27 studies (N = 3189) which met the inclusion criterion. The pooled proportion of patients with absence of pain at follow-up was 52.7% (95% confidence interval [95% CI], 50.85-54.56) and mild to moderate pain at follow-up was 33.43% (95% CI, 31.40-35.50). Quality of life improved in 88.21% (95% CI, 85.43-90.73) and complete ductal clearance was 70.69% (95% CI, 68.97-72.38) in the pooled patients.

CONCLUSIONS

The ESWL is an effective and safe management option in patients with chronic calcific pancreatitis patients with main pancreatic duct stone size greater than 5 mm who did not get adequate pain relief with conservative management.

Current status of endotherapy for chronic pancreatitis

Chronic pancreatitis is associated with varied morphological complications, including intraductal stones, main pancreatic ductal strictures, distal biliary strictures and pseudocysts. Endoscopic therapy provides a less invasive alternative to surgery. In addition, extracorporeal shockwave lithotripsy improves the success rate of endoscopic clearance of intraductal stones. However, recent data from randomised trials have shown better long-term outcomes with surgical drainage for obstructive pancreatic ductal disease. In patients with distal biliary strictures, stent insertion leads to good immediate drainage, but after stent removal, recurrent narrowing is common. Endoscopic drainage of pancreatic pseudocysts has excellent outcome and should be accompanied by pancreatic ductal stenting when a ductal communication is evident. In those who remain symptomatic, endoscopic ultrasonography-guided coeliac plexus block may provide effective but short-term pain relief. In this review, we present the current evidence for the role of endotherapy in the management of patients with chronic pancreatitis.

Endoscopic therapy in chronic pancreatitis: current perspectives

Endoscopic therapy in chronic pancreatitis (CP) aims to provide pain relief and to treat local complications, by using the decompression of the pancreatic duct and the drainage of pseudocysts and biliary strictures, respectively. This is the reason for using it as first-line therapy for painful uncomplicated CP. The clinical response has to be evaluated at 6-8 weeks, when surgery may be chosen. This article reviews the main possibilities of endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) therapies. Endotherapy for pancreatic ductal stones uses ultrasound wave lithotripsy and sometimes additional stone extractions. The treatment of pancreatic duct strictures consists of a single large stenting for 1 year. If the stricture persists, simultaneous multiple stents are applied. In case of unsuccessful ERCP, the EUS-guided drainage of the main pancreatic duct (MPD) or a rendezvous technique can solve the ductal strictures. EUS-guided celiac plexus block has limited efficiency in CP. The drainage of symptomatic or complicated pancreatic pseudocysts can be performed transpapillarily or transgastrically/transduodenally, preferably by EUS guidance. When the biliary stricture is symptomatic or progressive, multiple plastic stents are indicated. In conclusion, as in many fields of symptomatic treatment, endoscopy remains the first choice, either by using ERCP or EUS-guided procedures, after consideration of a multidisciplinary team with endoscopists, surgeons, and radiologists. However, what is crucial is establishing the right timing for surgery.

Efficacy of pancreatic stenting prior to extracorporeal shock wave lithotripsy for pancreatic stones

BACKGROUND

Extracorporeal shock wave lithotripsy is the first-line therapy for large pancreatic duct stones; however, it requires a long duration of therapy.

AIMS

To clarify the effect of pancreatic stenting prior to extracorporeal shock wave lithotripsy on shortening the duration of therapy and reducing complications.

METHODS

We retrospectively compared 45 patients who underwent pancreatic stenting prior to extracorporeal shock wave lithotripsy (stenting group) and 35 patients who did not undergo stenting prior to extracorporeal shock wave lithotripsy (non-stenting group) with regard to the cumulative number of shock waves required for stone fragmentation (stone size <3mm) and the rate of complications.

RESULTS

The stenting group was associated with a significantly lower cumulative number of shock waves in univariate analysis (log-rank, p=0.046) and multivariate Cox proportional hazard analysis (hazard ratio, 1.88; 95% confidence interval, 1.13-3.14; p=0.015) than the non-stenting group. The frequency of pancreatitis tends to be lower in the stenting group than the non-stenting group (2.2% [1/45] vs 11.4% [4/35]; p=0.162).

CONCLUSIONS

Pancreatic stenting prior to extracorporeal shock wave lithotripsy reduced the cumulative number of shock waves required for pancreatic stone fragmentation, and could be useful to shorten the duration of therapy.

Endoscopic management of chronic pancreatitis

Chronic pancreatitis (CP) is a common gastrointestinal illness, which affects the quality of life with substantial morbidity and mortality. The management includes medical, endoscopic and surgical approaches with the need for interaction between various specialties, calling for a concerted multidisciplinary approach. However, at the time of this publication, guidelines to establish care of these patients are lacking. This review provides the reader with a comprehensive overview of the studies summarizing the various treatment options available, including medical, surgical and endoscopic options. In addition, technological advances such as endoscopic retrograde cholangiopancreatogrophy, endoscopic shock wave lithotripsy and endoscopic ultrasound can now be offered with reasonable success for pancreatic decompression, stricture dilatation with stent placement, stone fragmentation, pseudocyst drainage, and other endoscopic interventions such as celiac plexus block for pain relief. We emphasize the endoscopic options in this review, and attempt to extract the most up to date information from the current literature. The treatment of CP and its complications are discussed extensively. Complications such as biliary strictures. pancreatic pseudocysts, and chronic pain are common issues that arise as long-term complications of CP. These often require endoscopic or surgical management and possibly a combination of approaches, however choosing amongst the various therapeutic and palliative modalities while weighing the risks and benefits, makes the management of CP challenging. Treatment goals should be not just to control symptoms but also to prevent disease progression. Our aim in this paper is to advocate and emphasize an evidence based approach for the management of CP and associated long term complications.

Endoscopic retrograde cholangiopancreatography for stone burden in the bile and pancreatic ducts

Stones in biliary and pancreatic ducts are entities that plague hundreds of thousands of patients worldwide every year. Symptoms can be mild (pain) to life threatening (cholangitis, severe acute pancreatitis). In the last few decades, management of these stones has transitioned from exclusively surgical to now predominantly endoscopic techniques. This article reviews the evolution of endoscopic techniques used in the management of stones in the common bile duct and pancreatic duct.

Italian consensus guidelines for chronic pancreatitis

This paper gives practical guidelines for diagnosis and treatment of chronic pancreatitis. Statements have been elaborated by working teams of experts, by searching for and analysing the literature, and submitted to a consensus process by using a Delphi modified procedure. The statements report recommendations on clinical and nutritional approach, assessment of pancreatic function, treatment of exocrine pancreatic failure and of secondary diabetes, treatment of pain and prevention of painful relapses. Moreover, the role of endoscopy in approaching pancreatic pain, pancreatic stones, duct narrowing and dilation, and complications was considered. Recommendations for most appropriate use of various imaging techniques and of ultrasound endoscopy are reported. Finally, a group of recommendations are addressed to the surgical treatment, with definition of right indications, timing, most appropriate procedures and techniques in different clinical conditions and targets, and clinical and functional outcomes following surgery.

Endoscopic treatment for chronic pancreatitis: indications, technique, results

Endoscopic treatment associated with or without extracorporeal shock wave lithotripsy (ESWL) for chronic pancreatitis has been employed for about 20 years. Although two randomized control trials have revealed the greater effectiveness of surgery as compared to endoscopic treatment for chronic pancreatitis, a considerable number of patients have successfully obtained complete and long-term relief from pain by the less invasive endoscopic treatment. In this review, we discuss the indications, techniques and results of endoscopic treatment and ESWL for painful chronic pancreatitis. We also discuss the characteristic clinical features that are predictive of a good response to endoscopic treatment and ESWL.

Endoscopic treatment of chronic pancreatitis

Treatment of chronic pancreatitis has been exclusively surgical for a long time. Recently, endoscopic therapy has become widely used as a primary therapeutic option. Initially performed for drainage of pancreatic cysts and pseudocysts, endoscopic treatments were adapted to biliary and pancreatic ducts stenosis. Pancreatic sphincterotomy which allows access to pancreatic ducts was firstly reported. Secondly, endoscopic methods of stenting, dilatation, and stones extraction of the bile ducts were applied to pancreatic ducts. Nevertheless, new improvements were necessary: failures of pancreatic stone extraction justified the development of extra-corporeal shock wave lithotripsy; dilatation of pancreatic stenosis was improved by forage with a new device; moreover endosonography allowed guidance for celiac block, gastro-cystostomy, duodeno-cystostomy and pancreatico-gastrostomy. Although endoscopic treatments are more and more frequently accepted, indications are still debated.

Extracorporeal shock wave lithotripsy for the treatment of pancreatic duct stones

The purpose of endoscopic therapy in chronic pancreatitis is to decompress the main pancreatic duct and to remove the obstacles that impede the ductal flow of pancreatic juice. The availability of extracorporeal shock wave lithotripsy (ESWL) has improved the results of endoscopic drainage of the main pancreatic duct and has also expanded the indications of endoscopic therapy for chronic pancreatitis. This article briefly reviews ESWL for pancreatic duct stones in patients with chronic pancreatitis, including our experience with ESWL. ESWL is an effective and safe procedure for endoscopically unremovable main pancreatic duct stones, and, in selected patients, ESWL alone may be effective.

Pancreatic duct stones in chronic pancreatitis: criteria for treatment intensity and success

BACKGROUND

The aim of the study was to evaluate interventional endoscopic management of pancreatic duct stones in patients with chronic pancreatitis by describing therapeutic methods and defining factors that predict technical success.

METHODS

Records were retrospectively analyzed for 125 patients with symptoms caused by chronic pancreatitis with pancreatic duct stones (single 43, multiple 82) treated by interventional endoscopy, including extracorporeal shockwave lithotripsy.

RESULTS

Technical success was achieved in 85% of patients (11 patients by mechanical lithotripsy, 114 by piezoelectric extracorporeal shockwave lithotripsy). There were no serious complications from lithotripsy. Univariate analysis disclosed a statistically significant association between treatment success and patient age as well as prepapillary location of stones. A greater therapeutic effort was necessary in patients with stones located in the tail of the pancreas, 2 or more stones, a stone 12 mm or more in diameter, or who have had a longer duration (>8 years) of the disease. However, with exception of the last parameter, correction for multiple testing of data removed statistical significance.

CONCLUSIONS

Extracorporeal shockwave lithotripsy enhances endoscopic measures for treatment of pancreatic duct stones when mechanical lithotripsy fails. Middle-aged patients in the early stages of chronic pancreatitis with stones in a prepapillary location proved to be the best candidates for successful treatment. Unfavorable patient-related or morphologic factors can be compensated for through more intense efforts at therapy.

Interventional treatment of chronic pancreatitis

Endoscopic treatment of chronic pancreatitis is becoming a reality: more and more endoscopy centres are developing the technique, and it is no longer a matter of extreme specialization. Among treatments which have been shown to be feasible, it is possible to distinguish between those approaches that are now considered as efficient with good results and very low risk (e.g. MPD drainage), or are efficient but with risks that seem to be lower than those of surgery (e.g. drainage of cysts), and drainage of the main bile duct, which is easy to perform, but, so far, has not been demonstrated enough as useful.

Endoscopic therapy for chronic pancreatitis

Endoscopic therapy for chronic pancreatitis is feasible and effective in selected patients. The management of pain and ductal obstruction is most effective if reversal of the obstructive process--stricture or stone--is successful and durable. Multiple endoscopic modalities are available, and new technologies will continue to advance the capabilities of therapeutic pancreatic endoscopists. Adjunctive treatments, such as ESWL, enhance the success of these techniques. These varied therapies, although attractive and theoretically sensible, have not been compared in a randomized, controlled fashion with standard surgical therapies. In this sense, they remain experimental. Nonetheless, these techniques are widely applied in advanced endoscopy centers worldwide, and uncontrolled individual series are expected to continue to expound on and demonstrate the effectiveness of these minimally invasive interventions until randomized, prospective studies become available.

Palliation of pain in chronic pancreatitis. Use of enzymes

According to the concept of negative feedback regulation of pancreatic enzyme secretion by proteases, treatment with pancreatic extracts has been proposed to lower pain in chronic pancreatitis by decreasing pancreatic duct pressure. The author, however, has demonstrated in healthy volunteers that intraduodenal application of porcine pancreatic extracts does not inhibit but rather stimulates pancreatic enzyme secretion. This is probably because of the high-protein content of porcine pancreatic extracts that may overwhelm a potential inhibitory effect of proteases. In a prospective placebo-controlled, double-blind multicenter study to investigate the effect of acid-protected porcine pancreatic extracts on pain in 43 patients with chronic pancreatitis, pain improved in most patients regardless of whether they started with placebo or verum. There was no significant difference between both treatment arms. In a meta-analysis, which included the author's study, six randomized, double-blind, placebo-controlled studies were evaluated. Statistical analysis demonstrated no benefit of the application of porcine pancreatic extracts to relieve pain in chronic pancreatitis. The author concluded that pancreatic extracts neither inhibit pancreatic enzyme secretion nor are they efficient in lowering pain in chronic pancreatitis.

The effect of ESWL of renal calculi on pancreatic function

Fifteen patients were treated by ESWL for renal calculi. The sagittal size of the head, neck and tail of the pancreas, and serum amylase, insulin, c-peptide and 24-hour urine amylase levels were estimated pre and post-treatment. Serum glucose, serum amylase and urinary levels remained within normal limits. Serum levels of insulin, c-peptide and the size of the gland increased but this was not statistically significant. There may be some danger to the pancreas during ESWL as there are some morphological changes even though there are no evident peptide changes. Caution should be taken if patients have a history of pancreatitis.

Sonographically-guided extracorporeal shockwave lithotripsy for pancreatic stones in patients with chronic pancreatitis

Over a 2 year period, 10 patients with pancreatic stones due to alcohol induced chronic pancreatitis (proven by endoscopic retrograde pancreatography) underwent extracorporeal shockwave lithotripsy. Prior to shockwave therapy, all patients underwent endoscopic sphincterotomy. Targeting of shockwave lithotripsy was exclusively performed under sonographic control. All patients were treated with a second generation electrohydraulic spark gap lithotriptor and fragmentation of concrements could be achieved in all cases. Complete duct clearance was confirmed in seven patients by endoscopic retrograde pancreatography in one session, with endoscopic fragment extraction by basket and/or balloon catheter. In three patients, balloon dilation of concomitant strictures located in the head of the pancreas was performed prior to fragment extraction. All stone-free patients showed no further symptoms over the follow-up period of 12 months. Three patients in whom complete extraction of fragments was not successful experienced minor symptoms over the 12 month follow-up period.

Pain in chronic pancreatitis

Pain in chronic pancreatitis is usually so intense and long-lasting that follow-up care of patients is often difficult and frustrating. Many therapeutical options to relieve pain have been recommended, but controlled studies are limited. The approach to patients with chronic pancreatitis complicated by pain is dependent on several factors. Medical therapy is initially attempted, but a switch to drainage procedure shortly thereafter in patients with persistent pseudocysts or a dilated pancreatic duct. Lithotripsy and endoscopic removal of pancreatic duct concrements may reduce pain in selected patients with a limited number of stones and strictures. In many patients, however, a drainage procedure cannot be offered and advantages and disadvantages of a resection or denervation procedure should be weighed against long-term treatment with analgetics. Resections should be limited to the most affected part of the pancreas. Usually this concerns the head. In such cases, a Whipple resection is often carried out, but duodenum-preserving procedures may offer several advantages.

Current role of extracorporeal shockwave therapy in surgery

In urology the introduction of extracorporeal shockwave therapy brought a revolutionary change to the management of urinary calculi. This inspired the introduction of shockwave therapy in several fields of surgery; it has been applied as a potential alternative to several operative procedures but is still experimental. So far, the major application of shockwave therapy has been lithotripsy of stones in the gallbladder, common bile duct, pancreatic duct and salivary gland ducts. Other applications are in the non-operative management of bone healing disturbances and in the inhibition of tumour growth. Steps towards selective thrombus ablation and pretreatment of heavily calcified arteries have also been made. In this review, the applications of extracorporeal shockwave therapy in several areas of surgery are discussed. It is concluded that, for selected patients, shockwave treatment may serve as a useful addition to the surgical armamentarium.

Role of extracorporeal shock wave lithotripsy in hepato-biliary-pancreatic surgery

Since the early 1980s extracorporeal shock wave lithotripsy (ESWL) has partially replaced major operative procedures in various fields of surgery. In the interest of the patient, it is important to determine the exact role of ESWL in surgery. Comparing our own prospectively followed patients with other patient series, we have tried to assess this role. We treated 133 patients with cholecystolithiasis, 80 patients with choledocholithiasis, and 17 patients with pancreatic stones using a second-generation lithotriptor, the Siemens Lithostar (Siemens, Erlangen, Germany). The results suggest a limited role of ESWL for cholecystolithiasis, in which it is reserved for patients with high operative risk and patients who reject an operation. For choledocholithiasis ESWL seems to become an integral part of the treatment in the elderly patient in whom endoscopic stone removal proved impossible. Finally, ESWL could become a first option for the treatment of intractable pain in patients with chronic calcifying pancreatitis.

Extracorporeal shockwave lithotripsy of pancreatic duct stones

Encouraging results with extracorporeal shockwave lithotripsy (ESWL) for pancreatic duct stones have been reported from Europe. We present our experience with the first two North American patients, treated with excellent results in one and limited clinical improvement in the other patient at 1 year follow-up. Targeting of pancreatic duct stones was achieved with either fluoroscopy or ultrasound.

Intraoperative endoscopic electrohydraulic lithotripsy of pancreatic stones

Two male patients with complications associated with chronic pancreatitis are described. In each patient, preoperative examinations revealed a large stone obstructing the main duct in the head of the pancreas. Lateral pancreaticojejunostomy was performed to relieve pain and prevent further attacks of pancreatitis. During each operation, the stone was fragmented under direct visual control with the use of a flexible choledochoscope and a contact electrohydraulic lithotriptor. The stone was removed and ductal flow through the head of the pancreas was reestablished. Our experience shows that endoscopic electrohydraulic lithotripsy facilitates operative removal of pancreatic stones deeply located in the head of the pancreas.

Extracorporeal lithotripsy of pancreatic stones in patients with chronic pancreatitis and pain: a prospective follow up study

Extracorporeal shock wave lithotripsy of pancreatic duct stones (largest stone 12 (SD) 6 mm) was performed in 24 patients with abdominal pain and a dilated duct system (main pancreatic duct 10 (3) mm). The procedure was well tolerated in all but two patients, who had a mild pancreatitic attack immediately after lithotripsy. Disintegration of the stones was achieved in 21 patients. This allowed complete clearance of the duct system by an endoscopic approach in 10 (42%) patients and partial clearance in 7 (29%) patients. Within a mean follow up period of 24 (14) months half of the patients showed complete or considerable relief of pain and alleviation of symptoms was achieved in seven patients. Relief of pain occurred more often after complete ductal clearance. There were no fatalities within the follow up period. These findings underline the value of a combined non-surgical approach, using endoscopy and adjuvant shock wave lithotripsy to patients with large pancreatic calculi and pain attacks.

Extracorporeal shock-wave lithotripsy of pancreatic calculi

Extracorporeal shock-wave lithotripsy (ESWL) has been used to disintegrate pancreatic stones located in the main pancreatic duct for 123 patients with severe chronic pancreatitis. Endoscopic management following ESWL is aimed at restoring the pancreatic flow to the duodenum. Stone disintegration was achieved in 122 patients, whereas a decrease in the main pancreatic duct diameter resulted in 111, and complete clearance of the main pancreatic duct was obtained in 72. Pain relief, complete (40/88) or partial (35/88), correlated significantly with the results of the endoscopic drainage of the main pancreatic duct (e.g., decrease in main pancreatic duct diameter). Relapsing pain was most often related to recurrent pancreatic duct obstruction. Of 76 patients whose body weight had decreased before ESWL, 54 gained weight. Improvement of the exocrine function, evaluated by the [14C]triolein breath test before and 11 months, on the average, after ESWL, was observed in 12 patients among 22 for whom this test was performed before and after treatment. Improvement of the endocrine function after relief of obstruction of the main pancreatic duct was less frequently recorded (4/41). ESWL of pancreatic stones is a new, safe, and highly effective method of facilitating the endoscopic procedures for relief of pancreatic duct obstruction in severe chronic pancreatitis.

Pancreatic ductal stones: frequency of successful endoscopic removal and improvement in symptoms

Pancreatic ductal stones may be responsible for attacks of acute pancreatitis (chronic relapsing pancreatitis) or exacerbations of chronic pain in patients with chronic pancreatitis. This study was undertaken to identify those patients with predominantly main pancreatic duct stones most amenable to endoscopic removal and to determine the effects on the patients' clinical course with such removal. Thirty-two patients with ductographic evidence of chronic pancreatitis and pancreatic duct stones underwent attempted endoscopic removal. Of the patients, 71.9% had complete or partial stone removal and 67.7% improved after endoscopic therapy. Symptomatic improvement was most evident in the group of patients with chronic relapsing pancreatitis. Factors favoring stone removal included (1) three or less stones, (2) stones confined to the head and/or body of the pancreas, (3) absence of a downstream stricture, (4) stone diameter less than or equal to 10 mm, and (5) absence of impacted stones. After successful stone removal, 25% of patients had regression of the ductographic changes of chronic pancreatitis and 41.7% had a decrease in the main pancreatic duct diameter. The only complication from therapy was mild pancreatitis in 8.2%. These data suggest that removal of pancreatic duct stones may result in symptomatic improvement. A longer follow-up will be necessary to determine whether endoscopic success results in long-standing clinical improvement and/or permanent regression of the morphologic changes of chronic pancreatitis.

Extracorporeal shock wave treatment of common bile duct stones: experience with two different lithotriptors at a single institution

Extracorporeal shock wave lithotripsy (ESWL) is a new treatment modality for retained common bile duct stones. Sixty-two patients (mean age 75 years, range 27-95 years) with retained common bile duct stones were treated with two different lithotriptors. One of the lithotriptors operated on the electrohydraulic principle (Dornier HM-3) (n = 13), the other on the electromagnetic principle (Siemens Lithostar) (n = 49). All HM-3 patients were treated under general anaesthesia, whereas with the Lithostar one patients was treated under general anaesthesia, 43 received analgesia and sedation and five had no analgesia at all. Patients treated with the Lithostar had more sessions (mean 1.9 versus 1.3, P less than 0.05) and needed more stock waves (mean 8611 versus 2534, P less than 0.001) than patients treated with the HM-3. Fragmentation was achieved in all patients treated with the HM-3 and in 42 (86 per cent) patients treated with the Lithostar. In this latter group ten patients underwent common bile duct exploration without complications. Eleven patients had transient haematuria after treatment with the HM-3 and two patients (one in each group) had a subcapsular haematoma of the right kidney, all without clinical sequelae. At follow-up (median: HM-3 43 months, Lithostar 18 months), none of the patients had biliary complaints. We conclude that ESWL of retained common bile duct stones in safe and effective with both lithotriptors and should be considered before surgery in the elderly or high-risk patient.