Fragmentation of gallstones by extracorporeal shock waves

In vitro interaction of lithotripter shock waves and cytotoxic drugs

The effect of a combination of lithotripter shock waves and cytotoxic drugs was examined in vitro. L1210 cells in suspension were exposed to shock waves during incubation with cislatin, doxorubicin, daunorubicin, THP-doxorubicin, or aclacinomycin. Proliferation was determined using the 3-4,5 dimethylthiazol-2,5 diphenyl tetrazolium bromide assay. Dose enhancement ratios were calculated for each drug in order to determine the effect of the additional exposure to shock waves. In addition, partition coefficients and IC50s of the drugs were determined. It was found, that the dose enhancement ratios increased for the drugs with decreasing cytotoxicity. The effect of all five drugs was enhanced by shock waves to a higher degree at 7 min incubation as compared to 50 min incubation. The effect of cisplatin was most significantly enhanced, with a dose enhancement ratio of 6.7 at 7 min incubation. The enhancement increased with the operating voltage used for generating the shock waves, and was only present when cells were exposed to shock waves during the incubation with the drug. An increase in cellular membrane permeability is proposed as the mechanism of interaction between shock waves and drugs.

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 and ursodiol versus ursodiol alone in the treatment of gallstones

The efficacy and occurrence of adverse effects after two forms of treatment were compared in 111 patients with biliary colic and radiolucent gallstones in this prospective, nonrandomized study. Fifty-four patients received extracorporeal shock-wave lithotripsy (ESL) plus ursodiol, and 57 patients received ursodiol alone. Among patients with a single stone (5-20 mm in size), no patient treated with ursodiol alone had a stone-free gallbladder at 6 or 12 months after treatment; of those treated with ESL plus ursodiol, 15 of 24 patients (63%) had a stone-free gallbladder at 6 months and 17 of 20 patients (85%) at 12 months. For patients with multiple stones (with an aggregate diameter of less than or equal to 30 mm), the incidence of a stone-free gallbladder was 2 of 43 patients (5%) at 6 months and 8 of 35 patients (23%) at 12 months in the ursodiol treatment group. In the ESL plus ursodiol group, the incidence of a stone-free gallbladder was 7 of 22 patients (32%) at 6 months and 9 of 20 patients (45%) at 12 months. Two patients in the ESL plus ursodiol group (4%) and 13 patients in the ursodiol group (24%) underwent cholecystectomy. Both patients in the ESL plus ursodiol therapy and 4 patients in the ursodiol group had emergency cholecystectomies because of acute cholecystitis. The remaining 9 patients in the ursodiol group had elective cholecystectomies. In this nonrandomized, prospective study, ESL plus ursodiol treatment produced stone-free gallbladders at a faster rate than ursodiol alone in patients with either single or multiple gallstones.

Treatment of common bile duct stones using mono-octanoin

A retrospective analysis of 48 patients undergoing mono-octanoin infusion via nasobiliary catheter following failure of endoscopic extraction of common bile duct stones is reported. Among 35 patients who received a complete course of treatment, nine (26 per cent) had duct clearance by the completion of the infusion and a further eight on subsequent endoscopic retrograde cholangiopancreatography (ERCP) (total 49 per cent). Two patients had a successful stone extraction after enlargement of the sphincterotomy (total non-surgical clearance rate 54 per cent). None of five patients with stones greater than 2 cm in diameter had stone clearance at the completion of the infusion and only one at subsequent ERCP. Among 13 patients receiving an incomplete course of treatment seven had clear ducts on repeat ERCP (54 per cent). Mono-octanoin infusion via a nasobiliary catheter is of limited value in the management of this difficult group of patients, although it may be successful in some.

Lithotripsy plus ursodiol is superior to ursodiol alone for cholesterol gallstones

The safety and efficacy of gallbladder extracorporeal shock-wave lithotripsy combined with 600 mg/day ursodiol were examined in 85 patients with radiolucent gallstones, 15 with lightly calcified gallstones, and 12 with radiolucent stones pretreated for greater than or equal to 2 months with 600 mg/day ursodiol. Results were compared with those of a well-matched lithotripsy-eligible group of 32 subjects treated with ursodiol alone (no lithotripsy). Pretreatment with ursodiol significantly improved while gallstone calcification interfered with fragmentation. Small gallstone size and number also aided fragmentation. Biliary lithotripsy plus ursodiol increased efficacy twofold compared with ursodiol therapy alone (47% vs. 22% of subjects gallstone free; P less than 0.02). Gallstones did not disappear in any subject with calcified gallstones (P less than 0.001) vs. lithotripsy). Product-limit analysis showed that the efficacy for gallstone dissolution increases in the following order: ursodiol alone, lithotripsy-ursodiol, lithotripsy-ursodiol pretreated with ursodiol (P less than 0.02, pairwise). Similar mean gallstone-dissolution rate constants (stone size divided by time to disappear) of stone fragments and whole gallstones during ursodiol therapy suggest that most fragments disappear by dissolution not expulsion. This finding explains why fragmentation appears to be the key predictor of disappearance and even partial fragmentation accelerates gallstone clearance.

Endoscopic management of bile duct stones

The surgical risk of common duct exploration for the treatment of biliary calculi is considerably higher than that of cholecystectomy. Therefore, introduction of endoscopic sphincterotomy in 1974 was a major advance. It has become the therapy of choice in cholecystectomized patients or in those with an increased operative risk. Endoscopic sphincterotomy has a mortality rate of around 1% and a morbidity rate of 7%. These figures compare favourably with open surgery, especially in old patients. The procedure fails in about 10% of all patients referred for endoscopic removal of their calculi. However, several techniques have been described or are currently under evaluation to overcome these failures: intracorporeal or extracorporeal lithotripsy, long-term stenting of the bile duct, or direct application of solvents. Long-term follow-up studies show that between 2% and 20% of successfully managed patients may develop recurrent stones, mainly caused by bile stasis and infection. Patients with a functioning gall-bladder and no concomitant gall-bladder stones probably do not require cholecystectomy after successful endoscopic treatment of their choledochal stones. While endoscopic stone removal has replaced surgery in the elderly frail patients it has no major advantages in the young and fit patients, especially when the gall-bladder is still in situ.

Extracorporeal shockwave lithotripsy and litholytic therapy in cholelithiasis

Extracorporeal shockwave lithotripsy (ESWL) and litholytic therapy were used in 100 patients over a period of 16 months. ESWL was carried out with a Lithostar Plus and chenodeoxycholic acid was used as the lytic agent, given until 3 months after complete disappearance of stones. Within a period of 8-12 months, stones disappeared completely in 82 per cent of the patients who had a single stone less than or equal to 20 mm in diameter and in 50 per cent of those with a single stone greater than 20 mm in size or with multiple stones. Complications requiring surgery developed in five patients: three had acute cholecystitis and two developed acute pancreatitis. Of the patients in whom complete stone clearance was achieved, two of 11 followed up developed recurrence of stones 4 months after cessation of lytic 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.

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.

Fragmentation of bile duct stones by extracorporeal shock-wave lithotripsy: a five-year experience

Over 5 yr, 103 elderly patients (mean age = 70 yr) with bile duct stones (mainly not amenable to endoscopic extraction) underwent adjuvant extracorporeal shock-wave lithotripsy using a first-generation kidney lithotripter. Disintegration of stones was achieved after a mean of 1.4 sessions in 92% of the patients. Spontaneous passage of fragments into the duodenum occurred in one fourth of the patients, and endoscopic extraction of fragments was necessary in 75% of the patients, resulting in complete clearance of the bile duct stones in 91 (88%) of 103 patients. The most important adverse effect was septic disease after extracorporeal shock-wave lithotripsy in 4% of the patients. The 30-day mortality rate was 1% (one patient), and another 15 patients died during a mean follow-up of 26 +/- 14 mo (mainly of causes unrelated to biliary tract disease). Two of 91 patients who had been rendered stone free were readmitted because of recurrent stone disease during the follow-up period. Of the 43 patients who still had their gallbladders during extracorporeal shock-wave lithotripsy, 14% subsequently underwent cholecystectomy. These data show that extracorporeal shock-wave lithotripsy of bile duct stones is a useful and safe adjunct to nonsurgical procedures for the removal of calculi in the biliary tree.

Treatment of symptomatic cholelithiasis in France. A decision analysis comparing cholecystectomy and biliary lithotripsy

To determine the potential role of extracorporeal shock wave lithotripsy (ESWL) in the treatment of symptomatic gallstone patients in France, a simulation model evaluated the health and economic effects of three different treatment strategies. Decision analysis of conventional cholecystectomy alone and either of two strategies using a combination of biliary lithotripsy and conventional cholecystectomy reveals that a strategy employing biliary ESWL results in a significant number of successfully treated patients, thus avoiding the risks and costs of abdominal surgery. Moreover, cost analysis shows that expanding the use of lithotripsy to all patients for whom the procedure is indicated increases the average cost per successfully treated patient, but, more importantly, decreases the overall costs incurred by the cohort. From a societal viewpoint, a policy using biliary ESWL in appropriate patients is superior to one of cholecystectomy alone, from both clinical and economic perspectives.

Pathophysiology and pharmacotherapy of cholelithiasis

Several factors are involved in the development of gallstone formation: formation of supersaturated bile; nucleation; formation, retention and adhesion of cholesterol crystals and eventually stone growth. The dynamics of the gallbladder may play a key role in the overall process. The pathophysiologic theory of cholesterol gallstone formation and the knowledge of their physico-chemical properties support the modern concept of gallstone therapy. Chenodeoxycholic and ursodeoxycholic have been widely used as cholesterol gallstone dissolving agents and evaluated in terms of efficacy and safety.

Laparoscopic cholecystectomy in young patients with sickle hemoglobinopathies

Nine young patients with sickle hemoglobinopathies successfully underwent laparoscopic cholecystectomy; no complications resulted from the procedure. The mean postoperative hospital stay was 1.6 days. This technique appears to be a safe and efficacious procedure in children with sickle hemoglobinopathies who require cholecystectomy for cholelithiasis.

The operative risk factors of cholelithiasis in the elderly

A total 725 patients with cholelithiasis were divided into three groups according to age, and the risk factors and morbidity rates compared. Group 1 consisted of those aged younger than 49 years, group 2 of those aged between 50 to 69 years, and group 3 of those aged over 70 years. In group 3, the incidence of calculi in the common bile duct was significantly higher than in the other two groups (p less than 0.05), and therefore, choledochotomy accompanying cholecystectomy was performed more often in this group (p less than 0.01). The rate of complications related to calculi and the presence of underlying disease were also higher in this group than in the two younger groups (p less than 0.05), as were preoperative abnormal liver or renal function tests, anemia and hypoproteinemia (p less than 0.05). The rate of positive bile cultures in group 3 was 75.6 per cent which was again significantly higher than in groups 1 and 2 (p less than 0.01). Postoperative complications appeared in 14.3 per cent of the group 3 patients, which was not statistically higher than in group 2 (9.7 per cent), but the percentages of both groups 2 and 3 were high compared to the 4.3 per cent of group 1 (p less than 0.01). The rates of complications directly attributable to the surgical procedures were 2.0 per cent in group 1, 4.8 per cent in group 2, and 5.1 per cent in group 3 with no significant differences between the three groups. There was no increase in the technical problems associated with the surgical procedures performed on the elderly patients and thus, if the operative risks are precisely evaluated and treated cautiously elderly patients should tolerate surgery for cholelithiasis well.

Methyl tert-butyl ether in the endoscopic treatment of common bile duct radiolucent stones in elderly patients with nasobiliary tube

Methyl tert-butyl ether is an effective dissolution agent for cholesterol stones. The aim of this work was to evaluate the effect of methyl tert-butyl ether on radiolucent common bile duct stones in patients in whom endoscopic extraction has failed. From September 1985 to September 1987, 1374 patients underwent endoscopic retrograde cholangiopancreatography in our Liver Unit. An endoscopic sphincterotomy was indicated in 195 patients with common bile duct (CBD) stones because of an age over 65 years and/or surgical contraindications. Endoscopic sphincterotomy was efficient in 187 patients, allowing complete stone removal in association with conventional endoscopic methods and mechanical lithotripsy in 170 patients. Twelve of the 17 patients with failure of conventional endoscopic treatments were either older than 75 years (11 patients; mean age, 86 +/- 4.5 years) or exhibited a surgical contraindication. Stones completely obstructed CBD in six patients and had a diameter exceeding 25 mm in the six other patients. These subjects were selected for stone dissolution by methyl tert-butyl either (MTBE) according to the following protocol. MTBE was directly infused into CBD through a nasobiliary catheter, twice daily for 4-13 days (mean, seven days). Bile duct opacification, repeated after MTBE treatment, revealed the complete disappearance of CBD stones in one patient, a decrease in stone size in five patients and no change in the six other patients. MTBE treatment was well tolerated except in three patients who complained from transient abdominal pains and nausea. At the second attempt of endoscopic treatment, CBD stones were found to be softened and easily broken up, allowing a complete clearance in six patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Dissolution of cholesterol gall stones using methyltertbutyl ether: a safe effective treatment

Methyltertbutyl ether (MTBE) administered by percutaneous transhepatic catheter rapidly dissolves radiolucent cholesterol gall bladder stones. However, complete dissolution and clearance of non-cholesterol debris is essential to prevent recurrence. In this study we analysed 25 consecutive patients with reference to efficacy and recurrence based on the presence or absence of non-cholesterol stone fragments after dissolution. Placement of the catheter was successful in 24 patients, one patient requiring cholecystectomy for bile peritonitis. MTBE was infused and aspirated continuously, four to six cycles per minute, resulting in rapid stone dissolution (median six hours; range 4-23 hours for solitary stones and median seven hours, range 4-30 hours for multiple stones). In 18 patients who had complete dissolution, four (22%) had recurrent stones within six to 18 months. Five patients had residual debris which failed to clear completely despite bile acid treatment. One patient with an incomplete rim of calcium in a large stone did not respond to MTBE treatment. A further patient required cholecystectomy for symptomatic recurrence. There were no serious side effects observed. MTBE treatment is a rapid, safe, and effective treatment for patients who refuse surgery or who for medical reasons cannot undergo cholecystectomy. The results of this study confirm that complete dissolution of all fragments is essential and may prevent recurrence.

Effects of high-energy shock waves on murine renal cell carcinoma

The effects of high-energy shock waves (HESW) on a murine renal cell carcinoma (RenCa) was investigated. In vitro exposure of tumor cells to HESW resulted in a dose-dependent reduction in cell viability as determined by trypan blue dye exclusion, plating efficiency, growth curve, and soft agar clonogenic assays. Activity of lactic dehydrogenase (LDH) was detected in the supernatant after the HESW treatment due to cellular destruction, and a dose-dependent increase in cytocidal effect was demonstrated. Ultrastructural changes with swelling and distorted cristae of mitochondria, vacuolation, ribosomal lysis, and chromatinolysis were observed in HESW-treated RenCa cells. Flow cytometric (FCM) study revealed that DNA content of RenCa cells diminished after 200 HESW treatment, and RNA content of tumor cells decreased markedly after 400 HESW treatments. Partial or complete inhibition of tumor growth was shown in both animal modalities of subcutaneous inoculation and intravenous injection with sequential lung metastases. This study stressed again that HESW may play a role in combinational protocol for the treatment of human renal cell carcinoma in certain circumstances.

Histological changes of the gallbladder and liver after extracorporeal shock wave lithotripsy for gallbladder

The histological changes of the gallbladder and liver following extracorporeal shock wave lithotripsy (ESWL) were investigated in a canine model. After performing ESWL on human cholesterol stones placed in the gallbladder of 8 dogs, the gallbladder and livers were removed for pathological study. The mucosa of the gallbladder showed erosion and ulceration in three of the eight dogs. Edema and bleeding were found in the stroma of the gallbladder beds. Hemorrhagic necrosis and vacuolar degeneration occurred in liver parenchyma adjacent to the gallbladder bed, but the portal area was fairly well preserved. It can be said that ESWL caused damage to both the liver and the gallbladder, but its effects on the liver may be only slight because of the preservation of the portal area.

Treatment of the Dunning prostate rat tumor R3327-AT1 with pulsed high energy ultrasound shock waves (PHEUS): growth delay and histomorphologic changes

We are interested in the interaction of pulsed high energy shock waves (PHEUS) on soft tissues treated in situ to evaluate its potential for therapeutic use. The experimental apparatus built by us was adapted from a lithotripter designed for clinical use. For the present studies we used the R3327-AT1 Dunning prostate tumor growing s.c. in the thigh of Copenhagen rats. The treatments consisted of four groups of eight animals each who received 500 or 2000 pulses at 1 or 5 Hz. Sham-treated tumor bearing animals served as controls (n = 11). During each PHEUS treatment, petechial bleeding of the skin at the point of entry and exit of sound appeared. Sonication at a repetition rate of five Hz seemed to induce more macroscopic damage in terms of hematomas and skin effects. The cytotoxic effects of PHEUS to tumor tissue were sufficient to induce a significant delay (p less than 0.05) in tumor growth but no clear-cut dose relationship was established. Histological studies revealed widespread early rupture of the fine vasculature with extravasation of erythrocytes. By 72 hr., in PHEUS treated tumors, a large necrosis was seen within the central zone which was never observed in sham-treated tumors. Our results clearly indicate that PHEUS has a cytotoxic potential. The observation of a rapid onset of hemostasis, stark hemorrhage and necrosis in the treatment field would suggest that vascular damage is an important contributing factor.

Acoustic pressure wave generation within an MR imaging system: potential medical applications

The static magnetic field of a magnetic resonance (MR) imaging system was used as a component of an electromagnetic transducer for generating acoustic pressure waves. To permit limited focusing, the transducer was constructed from a conductive thin plate shaped like a section of a sphere. The plate was placed within the static field of the MR unit (B0 = 1.5 T), and current pulses with a rise time of 73 nsec and amplitude of 1.0 kA were applied to it. Hydrophonic recording demonstrated a shock wave with a peak pressure of 4.8 MPa at the approximated focal point. MR guidance of lithotripsy would be particularly useful to limit undesirable soft-tissue damage. It is also suggested that the integration of an acoustic pressure wave generator with MR imaging and control provides a novel technology for the treatment of solid soft-tissue tumors.

Extracorporeal shock wave lithotripsy: an outpatient procedure

At many centers circumstances have dictated that extracorporeal shock wave lithotripsy (ESWL*) be performed on an outpatient (that is same-day surgery or 1-day stay) basis. At our center, Louisiana Lithotripter, Inc., which is a privately owned ESWL unit located at Tulane University Hospital, we have had the opportunity to treat patients in the inpatient and outpatient setting since inception. Since our first ESWL treatment on December 18, 1985 we have treated more than 2,500 patients. Additionally, our unit was named an American Urological Association Training Center in October 1986, resulting in more than 200 urologist, nurse and technician trainee visits. The first 1,779 cases through December 31, 1988 have been thoroughly reviewed. The rate of outpatient ESWL has increased from 22% of the first 100 cases to more than 90% of the last 100. The cumulative over-all rate reached 70%. Currently, more than 95% of our cases are planned as same-day procedures. Safe and effective outpatient ESWL is able to be performed with first generation technology, paving the way for appropriate clinical application to newer technological modalities.

Combined treatment of symptomatic gallbladder stones by extracorporeal shock-wave lithotripsy (ESWL) and instillation of methyl tert-butyl ether (MTBE)

Twenty-four patients with symptomatic gallbladder stones (12 radiolucent and 12 calcified) were treated by a combined approach of extracorporeal shock-wave lithotripsy (ESWL) and subsequent instillation of methyl tert-butyl ether (MTBE). The patients received a mean of 1500 +/- 185 shock-wave discharges. The mean instillation time of MTBE was 13 +/- 4.2 hr. Treatment was tolerated without major adverse effects. Within a time period of three to five days eight of 12 patients with pure radiolucent stones and four of 12 with calcified stones became stone-free. After a median follow-up of five months (range: one week to 26 months), a total of 11 patients (92%) with radiolucent stones and of eight patients (66%) of those with calcified stones were free of stones, fragments, or debris. These clearance rates appear high when compared with reports on monotherapy with ESWL or MTBE, suggesting a positive effect of a combined approach in selected patients. Two patients exhibited recurrent stones after six and seven months, respectively.

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 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.

Role of high total protein in gallbladder bile in the formation of cholesterol gallstones

While it is generally accepted that cholesterol supersaturation of bile is of key importance in the rapid formation of cholesterol crystals, the role of total biliary protein and pH in the pathogenesis of cholesterol gallstones is less well understood. The relation of cholesterol saturation, total protein, and pH was studied in 73 gallbladder bile samples with and 35 gallbladder bile samples without cholesterol crystals. In samples containing crystals, a trend to higher values of cholesterol and to a higher cholesterol saturation index was observed. However, significantly (P = 0.02) higher concentrations of total protein were found in samples with crystals [0.80 +/- 0.40 g/dL (8.0 +/- 4.0 g/L)] than in samples without crystals [0.63 +/- 0.26 g/dL (6.3 +/- 2.6 g/L)]. Moreover, of 22 bile samples with total protein concentrations greater than 10.0 g/L, cholesterol crystals were detected in all but 2. Total lipids, bile acids, phospholipids, and pH values were not significantly different in the two groups of bile samples. It was concluded that high biliary protein concentrations are frequently associated with cholesterol crystals and may, therefore, be a possible risk factor in the pathogenesis of cholesterol gallstones.

Treatment of gallstones with piezoelectric lithotripsy and oral bile acids. A multicenter study

The efficacy of the combination of piezoelectric lithotripsy and oral bile acids in the treatment of gallbladder stones was assessed. Three hundred and sixty-three patients with symptomatic radiolucent gallstones in functioning gallbladder were treated in five medical centers using the same protocol with the EDAP LT 01 lithotripter. No anesthesia, analgesia or sedation was used. After one session of lithotripsy, fragmentation was observed in 89% of the patients, and satisfactory fragmentation (fragments less than or equal to 5 mm) in 29%. The satisfactory fragmentation rate was higher in patients with solitary stones less than or equal to 20 mm than in patients with solitary stones 21-35 mm or multiple stones (p less than 0.001). After multiple sessions (mean 1.6 session/patient, range 1-5) the overall rate of satisfactory fragmentation was 50%. After 12 months on oral bile acid therapy, complete clearance of the gallbladder was observed in 69% of patients with solitary stones less than or equal to 20 mm, 25% of patients with solitary stones 21-35 mm and 37% of patients with multiple stones. No complication was observed during the lithotripsy. During follow-up under bile acid therapy, there were five complications (1.4%): four patients had acute cholecystitis and one had mild, self-limited pancreatitis. We conclude that piezoelectric lithotripsy with the EDAP lithotripter is a safe and effective treatment which can be performed in outpatients. Satisfactory fragmentation and rapid disappearance of stones are obtained mainly in patients with solitary stones less than or equal to 20 mm.

High-energy shock waves: in vitro effects

To date, there have been multiple studies on the effects of high-energy shock waves (HESW) on benign and malignant cells under in vitro conditions. The major problem in comparing and contrasting these studies has been the wide range of mechanical, biological, and analytical variables facing the investigator. However, if one takes the time to select out only those studies in which a wide range of experimental variables have been defined or controlled, then it becomes possible to begin to understand the effects of HESW on cells in vitro. With this in mind, the literature has been thoroughly reviewed. It would appear that HESW do cause cellular damage regardless of the cell's doubling time. The cell damage is likely due to the impact of cavitation and the attendant shear forces and jets that are produced by the shock waves as it passes through the cell suspension. The damage occurs both at the cell membrane and within the cell itself. With regard to the latter, it would appear that the mitochondria are most sensitive to HESW; however, damage also occurs within the nucleus and along the endoplasmic reticulum and in other cell organelles (eg, lyosomes). Applications of HESW to other clinical situations are currently being studied. One example of interest is the in vitro combination of chemotherapeutic agents and HESW to enhance the effect of a specific chemotherapeutic regimen on a given tumor cell line. Several investigators have noted a beneficial effect of this combination therapy in vitro; however, similar favorable results have not been obtained when the same or similar tumor system was studied in vivo.

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.

New trends in gallstone management

Many new therapies for the management of gallstone disease have been pioneered in the past decade. The object of this review is to equip the surgeon with the answers to all of the questions a patient will ask about gallstone therapy; the review is therefore didactic as well as comprehensive.

Medical dissolution of gallstones. Clinical experience of d-limonene as a simple, safe, and effective solvent

Retained gallstones in the bile ducts account for 60-70% of all the cases of postcholecystectomy syndromes. A solvent d-limonene preparation was injected directly to the biliary system of 200 patients to dissolve or disintegrate the retained gallstones. The outcomes were: retained stones completely disappeared in 96 cases (48%); partial dissolution in 29 (14.5%); chelating agent was also used with partial dissolution in 16 (8%); ineffective in 59 (24.5%). To make this method more effective, several guidelines should be observed including an in vitro trial dissolution test. Cautious observation for possible side effects and frequent hepatic and pancreatic function tests during the treatment with this preparation also should be performed.

Conventional versus laparoscopic cholecystectomy and the randomized controlled trial. Cholecystectomy Study Group

We considered using a randomized trial to assess the value of laparoscopic cholecystectomy in the treatment of symptomatic gallstones. The pros and cons for the timing of such a trial were in favour of not beginning the trial until surgeons learned to use the new procedure safely and effectively, and until key endpoints and outcome indices could be identified and assessed using valid measures. Instead an observational study was implemented to monitor the learning curve of surgeons as they mastered the laparoscopic equipment and procedures, and to assess the responses of the patients to the procedure. In the first 100 patients, the procedure proved to be as safe and feasible to use as conventional surgery, and there were strong benefits in terms of quicker recovery of the patients with less pain, discomfort, and a reduced length of hospital stay. The responses of the surgeons and the patients to the new procedure now place ethical constraints on the planning of a randomized controlled trial. Currently, comprehensive surveillance and monitoring of laparoscopic cholecystectomy is the only realistic method with which to assess the impact of this new technology in our clinic.

Dissolution of bile duct stones by a hydrophilized glyceromonooctanoin-bile-acid-EDTA emulsion

The clinical suitability of conventional glyceromonooctanoin (GMOC) and ethylenediaminetetraacetic acid (EDTA) containing solvents for the dissolution of common bile duct stones is questionable. To improve the solvent-stone contact and the miscibility with bile, GMOC was hydrophilized by the addition of polyethyleneglycol-caprylglyceride, polyethyleneglycol-sorbitan-etheroleyl-ester, and polyethyleneglycol-sorbitanlauryl-ester (PEG-GMOC). This product was mixed with a bile acid-EDTA (BA-EDTA) solution in a ratio of 1:2 (v/v) for cholesterol solubilizing and calcium complexing capacities. To determine clinical efficiency, the new solvent was infused via a nasobiliary tube in 16 patients with endoscopically nonextractable common bile duct stones and compared with a group of 16 patients treated with an alternating GMOC/BA-EDTA regimen. Continuous perfusion with PEG-GMOC-BA-EDTA led to a total (12 patients) or partial (3 patients) disappearance of the stones within 2-15 days. Similarly, alternating GMOC and BA-EDTA treatment dissolved the stones in 12 patients. The average volume of PEG-GMOC-BA-EDTA infused contained only 27% of the GMOC applied during the alternating therapeutic regime. This reduction of the GMOC dose was associated with a significant reduction of adverse effects such as emesis, diarrhea and biliary pain. We concluded that GMOC is equally efficient in the new hydrophilized form but it is clearly superior as far as side effects are concerned. In all, this supports its clinical suitability for the dissolution treatment of common bile duct stones.

Computed tomographic analysis of gallbladder stones: correlation with chemical composition and in vitro shock-wave lithotripsy

The recent advent of nonsurgical treatment for gallstones requires accurate in vivo analysis of their chemical composition in order to select the best candidates. As a preliminary work, we undertook an in vitro CT examination of 53 surgically removed gallstones and compared their CT patterns with their chemical composition. Those results were correlated with in vitro lithotripsy of the gallstones. The CT appearances were classified as follows: laminated (43%), dense (32%), rimmed (11%), isodense (8%) and faint (6%). The dense pattern contained a high calcium content. As the CT density increased, the calcium content increased, but the cholesterol content decreased proportionally. The number of shock waves needed to break down a gallstone less than 2 mm in size increased with stone volume and the cholesterol content increased but did not have any correlation with the calcium content level. As a result we found the CT examination to be a very sensitive method in detecting small amounts of calcium content in gallstones and the CT pattern and density of the gallstones were well correlated with their chemical composition, therefore in vivo CT examinations for ESWL candidates are desirable.

Analgesic Effects of Electroacupuncture in Extracorporeal Shock-Wave Treatment of Gallstone Disease

Thirty-four patients with gallstone disease were treated with extracorporeal shock-wave lithotripsy (E.S.W.L.). Analgesia was provided by means of electroacupuncture in ear and body acupuncture points. Electrostimulation was begun about 30 minutes before the start of shock-wave lithotripsy and continued until the end of treatment. The number of shock waves varied between 400 and 1200 per patient. The favourable results obtained with the above method may be compared with those obtained with classical epidural anaesthesia as well as with drug premedication with Droperidol, Fentanyl, and Diazepam. The good sedative and analgesic effect which was obtained by acupuncture widens its field of application.

Comparison of gall bladder bile and endoscopically obtained duodenal bile

In 10 patients with gall stone disease (eight women, two men; mean (SD) age 47.4 (13) years), bile was obtained by endoscopic aspiration after stimulation of the gall bladder with ceruletid and also by fine needle puncture of the gall bladder under local anaesthetic. The total lipid concentration of the puncture bile samples was mean (SD) 11.9 (4.7) g/dl, significantly higher than the endoscopic bile samples (3.9 (3.3) g/dl, p less than 0.001). Total bile acids, phospholipids, and biliary cholesterol (expressed in mol%) and cholesterol saturation index showed no significant differences between the two types of samples. The glycocholic acid concentration in the endoscopically obtained bile (27.7 (6.6) mol% v 23.3 (5.4) mol%; p less than 0.01) was significantly higher than the puncture bile samples. Puncture bile exhibited a significantly shorter nucleation time (3.5 (3.3) days v 19.6 (11.9) days; p less than 0.001). For determination of the nucleation time, endoscopic bile aspiration after gall bladder stimulation with ceruletid led to adequately concentrated samples in 50% of the study subjects. Cholesterol monohydrate crystal formation in native bile was observed in six samples of puncture bile and in three samples of the endoscopically obtained bile. The presence of cholesterol crystals and the determination of nucleation time in the puncture bile were the best discriminants between cholesterol and pigment gall stones and correlated well with computed tomogram analysis.

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.

Biliary extracorporeal shock wave lithotripsy in the treatment of an impacted stone in bile duct diverticulum

A calcified, retained stone impacted in a diverticulum of the distal common bile duct was successfully treated with biliary extracorporeal shock wave lithotripsy (BESWL). The stone fragments spontaneously passed within 1 week of lithotripsy treatment without the aid of further intervention. This case is unusual in that the stone lodged in a bile duct diverticulum proved inaccessible at the time of surgical exploration.

Gallstone clearance: a randomized study of extracorporeal shock wave lithotripsy and chemical dissolution

Following extracorporeal shock wave lithotripsy it is not known whether gallstone fragments are cleared from the gallbladder without the use of oral dissolution therapy. To assess the efficacy of lithotripsy and dissolution therapy, alone or in combination, 35 patients were randomized to one of three treatment groups: lithotripsy alone, dissolution therapy alone or combined lithotripsy and dissolution therapy. All patients had symptomatic gallstones, functioning gallbladders and comparable stone profiles. Lithotripsy was administered using a piezoelectric lithotripter. Dissolution therapy consisted of combined bile acid and terpene. Clearance was assessed at 6 months using ultrasound and oral cholecystography. Patients with less than 50 per cent stone clearance at the end of 6 months were considered failures. The number of patients with total or partial clearance in the combined group (7/10) was significantly greater than those in the lithotripsy alone group (0/10, P less than 0.002). Gallstone clearance following lithotripsy appears to be dependent upon dissolution therapy.