Extracorporeal shock-wave lithotripsy of gallstones without general anesthesia: first clinical experience

Review on Lithotripsy and Cavitation in Urinary Stone Therapy

Cavitation is the sudden formation of vapor bubbles or voids in liquid media and occurs after rapid changes in pressure as a consequence of mechanical forces. It is mostly an undesirable phenomenon. Although the elimination of cavitation is a major topic in the study of fluid dynamics, its destructive nature could be exploited for therapeutic applications. Ultrasonic and hydrodynamic sources are two main origins for generating cavitation. The purpose of this review is to give the reader a general idea about the formation of cavitation phenomenon and existing biomedical applications of ultrasonic and hydrodynamic cavitation. Because of the high number of the studies on ultrasound cavitation in the literature, the main focus of this review is placed on the lithotripsy techniques, which have been widely used for the treatment of urinary stones. Accordingly, cavitation phenomenon and its basic concepts are presented in Section II. The significance of the ultrasound cavitation in the urinary stone treatment is discussed in Section III in detail and hydrodynamic cavitation as an important alternative for the ultrasound cavitation is included in Section IV. Finally, side effects of using both ultrasound and hydrodynamic cavitation in biomedical applications are presented in Section V.

Biliary physiology and disease: reflections of a physician-scientist

A review is presented of Gustav Paumgartner's five decades of research and practice in hepatology focusing on biliary physiology and disease. It begins with studies of the excretory function of the liver including hepatic uptake of indocyanine green, bilirubin, and bile acids. The implications of these studies for diagnosis and understanding of liver diseases are pointed out. From there, the path of scientific research leads to investigations of hepatobiliary bile acid transport and the major mechanisms of bile formation. The therapeutic effects of the hydrophilic bile acid, ursodeoxycholic acid, have greatly stimulated these studies. Although ursodeoxycholic acid therapy for dissolution of cholesterol gallstones and some other nonsurgical treatments of gallstones were largely superseded by surgical techniques, ursodeoxycholic acid is currently considered the mainstay of therapy of some chronic cholestatic liver diseases, such as primary biliary cirrhosis. The major mechanisms of action of ursodeoxycholic acid therapy in cholestatic liver diseases are discussed. An attempt is made to illustrate how scientific research can lead to advances in medical practice that help patients.

Approach to idiopathic recurrent pancreatitis

Acute pancreatitis is caused by acute or chronic alcohol intake or choledocholithiasis in approximately 80% of cases. In the absence of alcohol abuse or gallstones, a variety of established and putative factors must be considered, any of which can cause a single or recurrent attacks of acute pancreatitis. When the underlying cause eludes detection following an initial thorough search and leads to a second attack, the term idiopathic acute recurrent pancreatitis (IARP) is applied. This article discusses IARP and its work-up.

ESWL and oral dissolution therapy. What factors influence results?

With the aim of identifying the criteria that have a decisive influence on the success of treatment of gallstones with ESWL and oral dissolution therapy, we investigated, in 117 patients, the stone-free rate as a function of sex, age, weight quotient, number of stones, total stone volume, and gallbladder function. The following inclusion criteria were applied: (1) the Munich criteria, (2) a follow-up period of at least 12 months, or (3) freedom from stones irrespective of the duration of the period of follow-up. Although, owing to the small number of cases involved, no significantly differing results were seen in the parameters investigated, clear tendencies were indeed observed. While age, sex, and weight quotient appear to have no influence on the stone-free rate, the number of stones, total stone volume, and gallbladder function do appear to have an effect on the results of treatment. Patients with solitary stones not more than 20 mm in diameter, and patients with a small total stone volume and good gallbladder function would appear to have the best chance of becoming stone-free within a short period of time, irrespective of age, sex, or girth.

Computed tomography after ESWL of gallbladder calculi

Computed tomography (CT) was performed on 88 patients before and after extracorporeal shock wave lithotripsy (ESWL) of gallstones to find the effects of ESWL on the gallbladder and surrounding liver tissue. Post-ESWL scans demonstrated a thickening of the gallbladder wall in 25 (28.4%) cases. In one patient an intrahepatic bilioma beside the gallbladder was seen 3 days after ESWL treatment. Hematoma of the gallbladder wall or the adjacent liver tissue was not seen, and neither a hydrops nor biliary-induced pancreatitis was observed. The authors conclude that while some patients undergoing ESWL will show some posttreatment abnormality on CT scans, the procedure is associated with a low frequency of serious gallbladder and liver trauma.

Gallbladder stones: shockwave therapy

Within the past 7 years, gallbladder lithotripsy by shockwaves has been proven to be a safe and effective non-invasive therapy for selected patients with gallstone disease. While regulatory decisions prevent shockwave therapy from being used more frequently in the USA, the number of patients treated in Europe and Asia is increasing constantly. At our institution, a relatively constant number of about 250 new patients per year have been treated since 1988 (Figure 4). About 20% of patients with gallstones are suitable for shockwave therapy according to present criteria. The rate of evacuation of all fragments is determined by the initial stone number and stone size, the success at stone fragmentation, adjuvant bile acid dissolution therapy, and gallbladder contractility. In contrast to laparoscopic cholecystectomy (Dubois et al, 1989; Perissat et al, 1989; Southern Surgeons Club, 1991), shockwave therapy does not require general anaesthesia. And in contrast to direct contact dissolution therapy of gallbladder stones using MTBE (Thistle et al, 1989), lithotripsy is non-invasive. In the majority of patients, complete fragment disappearance takes several months. Preliminary analyses of the cost-effectiveness of lithotripsy have revealed that lithotripsy, including retreatments and bile acid medication for recurrent stones, costs about as much as open cholecystectomy (Rothschild et al, 1990; Bass et al, 1991). The ideal patient for gallbladder lithotripsy has a single radiolucent stone < or = 20-25 mm in diameter in a functioning gallbladder (Figure 1). In patients with such stones, nearly all studies have confirmed a favourable outcome with rapid clearance of all fragments and a relatively low rate of stone recurrence. For carefully selected patients, extracorporeal shockwave lithotripsy is therefore an attractive non-invasive therapy.

Noninvasive therapy of gallbladder calculi with a radiopaque rim

Safety and efficacy of shock-wave lithotripsy and bile acid dissolution therapy of patients with gallbladder calculi with a radiopaque rim were evaluated. Eighty-six patients with symptomatic solitary stones were treated by this noninvasive therapy and were followed up to 18 months. Three different lithotripsy treatment modalities were used. Up to 1600 shock wave discharges were applied. Patients in group A (n = 20) were treated with an electrohydraulic water-bath lithotripter at a discharge voltage of 18 +/- 1 kV (mean +/- SD), group B patients (n = 25) were treated with an electrohydraulic water-cushion lithotripter at 19 +/- 2 kV, and group C patients were treated (n = 41) with the same lithotripter at 22 +/- 2 kV. Five to eight months after lithotripsy, 15% in group A were free of fragments compared with only 4% in group B (NS vs. group A), and 38% in group C had no stones (NS vs. group A; P = 0.007 vs. B). Thirteen to eighteen months after lithotripsy, the respective results were 59% in group A, 37% in group B (NS vs. group A), and 68% in group C (NS vs. group A; P = 0.05 vs. group B). Patients with fragments of less than or equal to 3 mm in diameter showed significantly better fragment clearance than those with larger fragments. The frequency of adverse effects was not significantly different between the three groups. Biliary colic occurred in 43% of the patients and mild biliary pancreatitis in 3 patients. Endoscopic sphincterotomy was required in 1 patient, and elective cholecystectomy was performed in 6 patients. Using a water-cushion lithotripter at high-power setting, selected patients with solitary gallbladder stones with a radiopaque rim may be treated safely and successfully by shock-wave lithotripsy combined with bile acid dissolution therapy.

Cost-effectiveness of extracorporeal shock-wave lithotripsy versus cholecystectomy for symptomatic gallstones

To evaluate the cost-effectiveness of extracorporeal shock-wave lithotripsy vs. cholecystectomy for symptomatic gallstones, a model was constructed that projects charges and survival for both treatments. For a 45-year-old woman with one small stone, treatment with extracorporeal shock-wave lithotripsy rather than cholecystectomy is projected to result in an average gain of only 3 days of life and an average increase in direct medical charges of $1729 over 5 years of follow-up. The resulting marginal cost-effectiveness of extracorporeal shock-wave lithotripsy vs. cholecystectomy is $216,000 of extra charges per year of life gained with extracorporeal shock-wave lithotripsy. Extracorporeal shock-wave lithotripsy is projected to be much more cost-effective for elderly than for young patients (10-20-fold difference), but considerably less cost-effective for multiple stones than a single stone (2-4-fold difference), and less cost-effective for women than men (twofold difference). Adjusting for effects of morbidity on quality of life, extracorporeal shock-wave lithotripsy is projected to have slightly better quality-adjusted survival than cholecystectomy for the small subset of patients with one stone (by 8 to 43 days at 5 years) but not for young patients with multiple stones. It is concluded that decisions about appropriate use of extracorporeal shock-wave lithotripsy should consider the effects of patient characteristics on clinical and economic outcomes.

Extracorporeal shock wave lithotripsy of gall stones: an in vitro comparison between an electrohydraulic and a piezoceramic device

A comparative study of the effectiveness of two types of lithotripter in fragmenting gall bladder stones is reported. The machines used were a Piezolith 2300, which generates shock waves by the piezoceramic principle, and a Dornier MPL 9000, which produces the shock waves by underwater spark discharge. With each machine, corresponding stones of 45 pairs of weight and volume matched calculi (median volume 0.5 cm3, median diameter 10.5 mm) obtained at cholecystectomy were treated. All stones were successfully disintegrated (fragments smaller than 2 mm) with up to 5400 (median 628) shocks with the Piezolith and 3450 (median 428) shocks with the MPL 9000 lithotripters. With the Piezolith, operating at the highest power setting, a 1.65 fold median higher number of shocks was required for stone fragmentation than with the MPL 9000 at a medium power setting. Stone volume seemed to be the only determinant which affected ease of fragmentation; composition and density of the stones as assessed by computed tomography did not seem to be governing factors.

Extracorporeal shock wave lithotripsy for biliary stones

Extracorporeal shock wave lithotripsy is a noninvasive technique for treatment of patients with gallbladder and bile duct stones. Selected patients with gallbladder stones can be treated on an outpatient basis without general anesthesia and may return to full activity within 1 or 2 days. Stone-free rates of 40% to 60% at 6 months have been achieved in most reported series with minimal morbidity. Bile duct stone lithotripsy has achieved stone clearance in 80% of patients in whom conventional methods were unsuccessful and therefore constitutes a valuable second-line treatment for these patients.

Review article: bile acid therapy

Over the past 3 years there has been a renewed interest in bile acid therapy not only because of the promising results obtained by combining this therapy with extracorporeal shock-wave lithotripsy for rapid gallstone dissolution, but also because of its novel use as a treatment for primary biliary cirrhosis. This article reviews the use of bile acids for both these indications.

Acute cholecystitis in the emergency department

Acute cholecystitis is a frequent consideration in patients presenting to the emergency department with the challenging complaint of upper abdominal pain. It is estimated that 20% of American adults have gallstones, and of these a large percentage (about one-third) will at some point develop acute cholecystitis. The epidemiology and associated risk factors of acute cholecystitis are briefly reviewed along with the pathogenesis and clinical presentation of the disease. Finally, an approach to the diagnosis in the emergency department and suggested management is discussed including a comparison of the strengths and weaknesses of ultrasonography and hepatobilary scintigraphy.

Extracorporeal shock-wave lithotripsy of bile duct calculi. An interim report of the Dornier U.S. Bile Duct Lithotripsy Prospective Study

A multi-institutional study to evaluate the efficacy, clinical application, and safety of extracorporeal shock-wave lithotripsy (ESWL) with the Dornier HM-3 or HM-4 lithotripter for bile duct calculi (BDC) was initiated in September, 1987. Symptomatic patients who entered into this prospective trial had BDC in the common bile duct and/or the intrahepatic, cystic or lobar ducts of the liver that were inaccessible or untreatable by papillotomy or percutaneous stone extraction. The study excluded gallbladder stones. Nasobiliary (54.4%) or transhepatic catheters (10.5%) and T-tube or cholecystostomy tubes (17.5%) or combinations (14.0%) permitted access for radiographic contrast to allow fluoroscopic monitoring of stone position and fragmentation. Exclusion criteria included pregnancy, failure to localize the stone, disturbances of coagulation, pacemakers, or vascular aneurysms or large bones that lie in the focal axis of the shock waves. Eleven institutions treated 42 patients (23 male, 19 female) with BDC; age range was 25 to 95 years (mean +/- SD, 73.5 +/- 13.8) and ASA risk category was 1 to 4 (mean, 2.3 +/- 0.8). Fourteen patients (33.3%) had a single BDC; 28 had 2 to 8 stones (mean, 2.7 +/- 1.8) ranging in size from 6 mm to 30 mm (mean, 18.5 +/- 6.4). The majority (66.7%) of patients were postcholecystectomy. The 42 patients received 57 ESWL treatments consisting of 600 to 2400 shocks per treatment (mean, 1924 +/- 289) at 12 to 22 kV (mean, 18.5 +/- 1.9) administered over 20 to 125 minutes (mean, 52.9 +/- 20.8). General anesthesia was used in 32% of the treatments; the majority were treated with epidural or regional block (42.1%), local infiltration (28.1%), or intravenous sedation (38.6%). Fifteen patients (35.7%) required two ESWL treatments. Stone fragmentation occurred in 94.6% of evaluable patients and in 90.4% of ESWL treatments, respectively; however, BDC fragments remained in 59.5% of patients 24 hours after treatment (diameter less than or to 3 mm, 12%; 4 to 9 mm, 16%; greater than or equal to 10 mm, 68%). Some patients (50%) required adjunctive procedures to achieve stone removal that included endoscopic extraction (n = 10; 47.6%), biliary lavage (n = 8; 38.1%), endoscopic bile duct prosthesis (n = 1; 4.8%), and operation (n = 2; 9.5%). ESWL treatment complications during hospitalization were observed in 15 patients (35.7%) and were present in four (9.5%) at discharge. Complications included macrohematuria (5%), biliary pain (15%), biliary sepsis (5%), hemobilia (10%), ileus (2.5%), and adverse pulmonary changes (7.5%). One patient developed pancreatitis before ESWL at ERCP that resolved prior to discharge.(ABSTRACT TRUNCATED AT 400 WORDS)

Extracorporeal shock wave lithotripsy (ESWL) in the management of complex biliary tract stone disease

The use of extracorporeal shock wave lithotripsy (ESWL) in the management of ten patients with complex biliary tract stones is described. General or epidural anesthesia was used in all cases, and stone fragmentation was performed, using an unmodified Dornier HM3 waterbath lithotripter (Dornier Medical Systems Inc., Marietta, GA). In all cases, biliary drainage was established before the procedure to allow contrast visualization during and after the procedure, as well as to ensure free drainage of the common bile duct. Indications for ESWL included failure of basket extraction (4 cases), unfavorable anatomy (duodenal diverticulum, previous Billroth II reconstruction, hepatic duct stone, gallbladder stone, cystic duct remnant stone), and immaturity of the T-tube tract (2 cases). Cholangitis was the presenting diagnosis in four cases. Fragmentation of the stones was successful in all patients; in two cases, two ESWL sessions were needed for stone disruption. Morbidity was minimal (there was a minor elevation of LDH and transaminases and asymptomatic hemobilia and hematuria); pancreatitis did not occur. After ESWL, hospital stays ranged from 1 to 13 days (mean of 5.3 days). ESWL can be a valuable adjunct in the management of patients with complex biliary stones.

A retrospective analysis of 3 year's experience of an interdisciplinary approach to gallstone disease including shock-waves

1206 patients with gallstone disease were treated between January 1985 and December 1987, using an interdisciplinary concept that included surgery, endoscopic sphincterotomy, and extracorporeal shock-wave lithotripsy (ESWL). Twenty-five per cent of the patients who were admitted for gallbladder stones were treated by ESWL, whereas 75% underwent surgery. Mortality of elective treatment for gallbladder stones amounted to 0.25% (0.4% in surgery, 0% in ESWL). Postoperative complication rate was low (4.2% in surgery, 7.0% in ESWL). After ESWL treatment, 80% of the patients were free of stones after a follow-up period of 1 year. Recurrence rate in these patients amounted up to 10%; in seven of 70 patients, mean follow-up period was 6 months after complete disappearance of stones. Twenty-seven per cent of all patients who were admitted for bile duct stones underwent surgery, whereas in the other 73%, calculi were removed via endoscopy. ESWL treatment was used additionally, if necessary. Fragments were left behind in three of 75 patients (4.0%) after surgical treatment, and in 7 of 200 patients (3.5%) after endoscopic and ESWL treatment, respectively. In the latter group, three patients (1.5%) required an additional operation. There were no deaths in either of the groups. The use of ESWL for treatment of gallbladder stones needs to be evaluated in long-term follow-up studies. Thus far, surgery remains the dominating method. Endoscopic procedures, eventually combined with ESWL, represent the preferred treatment for patients with bile duct stones.

Cholesterol gallstone disease: the current status of nonsurgical therapy

Gallstone disease is a common disease that appears to be related to a Western diet. The underlying pathogenesis is a subtle alteration in the liver such that excessive cholesterol is extracted from the liver cell by bile acids undergoing an enterohepatic recirculation. Gallstone disease progresses through well-defined stages, beginning with a bile supersaturated with cholesterol and proceeding to crystal formation, stone growth, and finally symptoms caused by impaction of a stone in either the cystic duct or the common bile duct. The natural history is that most stones never cause symptoms. Stones that cause symptoms have been present for an average of 12 years. The treatment of truly asymptomatic stones should be observation. Ultrasonography of the right upper quadrant is the gold standard for the diagnosis of stones in the gallbladder. Endoscopic retrograde cholangiopancreatography (ERCP) is the gold standard for the diagnosis of stones in the common bile duct. Oral cholecystogram (OCG) helps select patients who have noncalcified, floating stones that may be dissolved with bile acids or methyl tertiary butyl ether (MTBE). Therapy with chenodiol has been a disappointment because of a low complete response rate. The ideal candidate for attempted dissolution with chenodiol would be a thin woman with hypercholesterolemia and a small number of symptomatic, small, floating, radiolucent gallstones. Ursodeoxycholic acid (Urso), when it is available, will have all of the attributes of chenodiol and virtually none of the side effects. Rapid dissolution of gallstones with MTBE shows great promise of being a generally available means of dissolving gallstones. Extracorporeal shock wave lithotripsy also shows promise, but its general availability may be limited by the cost of the equipment needed. As of now, the treatment of choice for symptomatic gallstones remains cholecystectomy, unless there is a compelling reason not to operate.

Shock-wave lithotripsy of gallbladder stones. The first 175 patients

To substantiate the early results of extracorporeal shock-wave fragmentation of gallstones, we used this nonsurgical procedure to treat 175 patients with radiolucent gallbladder calculi. Chenodeoxycholic acid and ursodeoxycholic acid were administered as adjuvant litholytic therapy. The gallstones disintegrated in all patients except one and completely disappeared in 30 percent of all patients within 2 months after lithotripsy, in 48 percent at 2 to 4 months, in 63 percent at 4 to 8 months, in 78 percent at 8 to 12 months, and in 91 percent at 12 to 18 months. In patients with solitary stones up to 20 mm in diameter, the corresponding values were 45, 69, 78, 86, and 95 percent, respectively. Shock-wave therapy had no adverse effects except cutaneous petechiae (14 percent) and transient gross hematuria (3 percent). One third of the patients had one or more episodes of biliary colic before all the fragments disappeared. Two patients had mild pancreatitis, which necessitated endoscopic sphincterotomy in one. The patient with insufficient stone fragmentation underwent elective cholecystectomy; no additional operations were necessary. Extracorporeal shock-wave lithotripsy combined with medical therapy for stone dissolution is a safe and effective treatment in selected patients with radiolucent gallbladder calculi.

Biliary stones: treatment by shock-wave lithotripsy

Extracorporeal shock-wave lithotripsy has been introduced as a novel nonsurgical therapy for gallstone disease. To substantiate the initial results, more than 400 patients with biliary calculi have been treated. In selected patients with gallbladder stones, complete clearance of all stone fragments can be expected within 1 year in about 80%. In patients with bile-duct stones not amenable to endoscopic measures, sufficient stone fragmentation by extracorporeal shock waves was achieved in about 80%. Extracorporeal shock-wave lithotripsy is a safe and efficient therapy for selected patients with gallbladder calculi. For patients with bile-duct stones not amenable to endoscopic measures it offers a nonsurgical alternative.