Fragmentation of gallstones by extracorporeal shock waves

The cytocidal effect of high energy shock waves on human prostatic tumour cell lines

This report describes the effect of high energy shock waves (HESW) generated by a Siemens Lithostar on four human prostatic carcinoma cell lines in vitro. The effects of temperature, shock wave energy, cell density and the number of HESW were investigated. Pressure measurements were carried out in the focus of the lithotriptor and inside test tubes that were placed in the focus. Direct cell kill was inversely related to temperature, whereas a linear relationship was found with shock wave energy. Cell kill appeared to be independent of cell density. All four cell lines were sensitive to the treatment with HESW, but displayed a different dose-response pattern. In vitro treatment of PC-3 cells retarded their growth upon injection into nude mice. It is concluded that human prostatic tumour cells are killed by HESW. Therefore, HESW could be of potential value in tumour treatment.

Clinical trials of gallstone lithotripsy

All of the information to date suggests that extracorporeal shock-wave lithotripsy will in many patients be a safe and effective method of dealing with uncomplicated gallstone disease. Litholytic drugs appear to be an important adjunct to the procedure and may play a significant role in minimizing stone recurrence. Ongoing studies will further delineate suitable candidates.

Extracorporeal shock-wave lithotripsy of the common bile duct stone with ultrasound localization

Extracorporeal shock-wave lithotripsy with ultrasonographic localization of the common bile duct stone was successfully performed. The apparatus used is described and the advantages and disadvantages of ultrasonographic versus X-ray common bile duct stone localization are discussed.

The lessons from in vitro lithotripsy for the clinical treatment of gallstones

Fifty-eight gallbladder stones were treated in vitro, using a Wolf Piezolith 2300 lithotripter, to discover whether complete fragmentation (i.e., no particles greater than 2 mm diameter) could be achieved by lithotripsy alone. In 16 stones this was accomplished with up to 6000 shocks being administered. The degree of fragmentation was judged first by eye during the experiment and then by both microscopy and sieving of the debris. Eye judgement proved to be an unreliable indicator with 23 of the 42 stones in the failed lithotripsy group receiving 6000 shocks or less. Cholesterol analysis and high resolution radiography revealed no significant differences between the successfully and unsuccessfully fragmented stones, but X-ray diffractometry did show a higher incidence of inorganic calcium salts in the latter group. This study shows that lithotripsy can successfully fragment gallbladder stones, but that a minimum of 6000 shocks, using the Piezolith 2300, should be given to ensure adequate treatment. Additionally, the presence of radiopaque stones does not necessarily preclude successful treatment by this method.

Retrograde biliary ultrathin endoscopy enhances biopsy of stenoses and lithotripsy

Forceps biopsies of biliary stenoses are difficult to direct under fluoroscopy and for this reason may give spurious results. In addition, fluoroscopy does not prevent the electrohydraulic lithotripsy (EHL) probe from damaging the bile duct wall. Retrograde biliary endoscopy with the ultrathin endoscope (UTE) was tested in 12 patients to guide biopsies and in 6 patients to guide EHL. Results of biopsies were confirmed by surgery or the disease course in each of the 12 patients. Only one stone could not be fragmented and removed because the EHL probe could not be properly placed. The diagnosis of biliary stenosis may be markedly enhanced by using a UTE although at the risk of an endoscopic sphincterotomy and subsequent biliary infection. EHL with UTE is difficult and time consuming but further technical development may make it more practical immediately following sphincterotomy.

Fragmentation of biliary calculi by means of extracorporeally generated piezoelectric shock waves

A new extracorporeal piezoelectric lithotripter was tested for its gallstone disintegration capability. A total of 177 surgically removed gallbladder stones were submitted to piezoelectric shock-wave treatment. Prior to shock-wave application, the diameter, weight, and volume of all the stones and CT density and MR signal intensity of selected stones were determined. After shock-wave application, the chemical composition of the stones was investigated by x-ray diffractometry and/or infrared spectrometry. All the stones (maximum diameter 6-30 mm) were successfully fragmented; calculi with a maximum diameter of 17 mm, a maximum weight of 1800 mg, and a maximum volume of 2 cc were regularly disintegrated into fragments less than or equal to 4 mm. The number of shock waves required correlated most closely with volume (r = 0.82, P less than 0.001), weight (r = 0.81, P less than 0.001) and, to a somewhat lesser degree, diameter (r = 0.62, P less than 0.001). No correlation was found between the chemical composition, CT density, or MR intensity of the calculi and the number of pulses needed for fragmentation.

Short-term effects of extracorporeal shock wave lithotripsy on the human gallbladder

Extracorporeal shock wave lithotripsy (ESWL), whereby shock wave energy is focused upon gallstones causing their disintegration into fragments sufficiently small to be passed via the biliary system, offers a promising non-invasive alternative to surgery for gallstone disease. The tissue effects in humans of ESWL are poorly characterized and no systematic study of the tissue effects of ESWL by piezoelectrically generated shock waves has been published. Sixteen patients for elective cholecystectomy were therefore subjected to ESWL before surgery and detailed histology of the gall-bladders (including scanning electron microscopy of the mucosa) was compared with that from 20 age/sex-matched control cases. The gall-bladders treated by ESWL, in addition to showing the histological changes associated with chronic cholecystitis, showed serosal vasodilatation, mural oedema, and serosal and mucosal petechial haemorrhages focally over the entire surface. Between 10 and 90 per cent epithelial denudation was observed, but all cases showed surviving columnar epithelial cells in the crypts. No case showed vascular thrombosis, tissue necrosis, or acute inflammation. These tissue effects are likely to be reversible and unlikely to present a risk of perforation, although the long-term clinicopathological effects await investigation.

Removal of common bile duct stones by the combination of percutaneous balloon dilatation and extracorporeal shock-wave lithotripsy

Endoscopic papillotomy may not be possible in patients who have previously undergone gastric surgery. We describe the successful treatment of such a patient with ultrasound-guided, percutaneous transhepatic biliary drainage, followed by balloon dilatation of the sphincter of Oddi and extracorporeal shock-wave lithotripsy. Combinations of new treatment forms may be necessary and effective when single forms of treatment fail.

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)

In vitro cytotoxic activity of lithotripter shock waves combined with adriamycin or with cisplatin on L1210 mouse leukemia cells

The effect of a combined treatment with shock waves generated by a lithotripter and Adriamycin or cisplatin was examined in cells that acutely survived exposure to shock waves and proliferated afterwards. Batches of 2 x 10(6) cells were exposed to the respective drug for 50 min or for 50 min plus 72 h. During the 50-min drug exposure 500 shock waves were applied at 25 kV. The growth as a percentage of the control was determined after 72 h by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Cells treated with shock waves alone showed a growth inhibition as compared to control cells. For a 50-min drug exposure with Adriamycin the dose enhancement ratio did not exceed 1.3. For a 50-min drug exposure with cisplatin at concentrations of 0.5 micrograms/ml and 5.0 micrograms/ml, growth (as a percentage of the control) after combined treatment was significantly reduced as compared to cisplatin treatment alone; the dose enhancement ratio was 3.2 at 50% growth compared to the control. This indicates that shock waves can increase the susceptibility of L1210 cells to cisplatin. For a 50-min plus 72-h drug exposure no effect of an additional treatment with shock waves, as compared to chemotherapy alone, could be observed.

Review article: dissolution of gallstones in the biliary tree

There are a variety of methods for dissolving gallstones in the biliary tree, which include oral therapy and direct contact dissolution. Cholesterol gallstones are most amenable to dissolution. Developments in non-operative physical methods to remove gallstones (particularly endoscopic papillotomy and extracorporeal shock-wave lithotripsy have diminished the use of chemical dissolution. However, in selected patients, there remains a place for chemical dissolution, but often in conjunction with the physical techniques.

[Percutaneous transhepatic laser lithotripsy of gallstones--results of animal experiments]

Since laserinduced shock wave lithotripsy of gallstones is possible for treatment of common bile duct stones, the percutaneous transhepatic laserlithotripsy of stones in the gallbladder is examined in an animal study. In 8 animal experiments it could be shown that puncture of the gallbladder, dilatation of the working channel, (laserinduced) shock wave lithotripsy, removal of the fragments and the instruments are possible in one session. Neither when performing simple closure of the wound by suture nor by fibrinsealing severe side-effects could be recognized. After laserlithotripsy ablation of epithelium and hematomas can be observed, which are restituted within one month. The experiments show that in organ-saving shockwave lithotripsy there is no need for waiting for the development of a fistula and the percutaneous approach can be simplified.

Effects of cholecystectomy on the kinetics of primary and secondary bile acids

Removal of the gallbladder is thought to increase formation and pool size of secondary bile acids, mainly deoxycholic acid (DCA), by increased exposure of primary bile acids (cholic acid [CA], chenodeoxycholic acid [CDCA]) to bacterial dehydroxylation in the intestine. We have tested this hypothesis by simultaneous determination of pool size and turnover of DCA, CA, and CDCA in nine women before and at various intervals after removal of a functioning gallbladder. An isotope dilution technique using marker bile acids labeled with stable isotopes (2H4-DCA, 13C-CA, 13C-CDCA) was used. After cholecystectomy, concentration and output of bile acids relative to bilirubin increased (P less than 0.02) in fasting duodenal bile and cholesterol saturation decreased by 27% (P less than 0.05) consistent with enhanced enterohepatic cycling of bile acids. Three months after removal of the gallbladder bile acid kinetics were in a new steady state: pool size and turnover of CDCA were unchanged. Synthesis of CA, the precursor of DCA, was diminished by 37% (P = 0.05), probably resulting from feedback inhibition by continuous transhepatic flux of bile acids. The fraction of CA transferred after 7 alpha-dehydroxylation to the DCA pool increased from 46 +/- 16 to 66 +/- 32% (P less than 0.05). However, this enhanced transfer did not lead to increased input or size of the DCA pool, because synthesis of the precursor CA had decreased.

Tissue reactions under piezoelectric shockwave application for the fragmentation of biliary calculi

The tissue reactions that occurred during piezoelectric shockwaves for the fragmentation of biliary calculi were investigated in 10 surgically removed stone containing human gall bladders and in acute (six dogs) and chronic (six dogs) animal experiments. Before and after shockwave (500, 1500 or 3000) in the anaesthetised dogs, computed tomography (CT), magnetic imaging (MRI) and laboratory tests were done; treatment was carried out under continuous ultrasonographic control. Shockwave applications to the human gall bladders resulted in disintegration of the stones with no macroscopically or microscopically detectable tissue changes. In acute animal experiments, small haematomas were observed in all six animals at surfaces, but also inside the liver and gall bladder (max diameter 25 mm). Perforation or intra-abdominal or pleural bleeding did not occur. In chronic experiments, no macroscopic, and only slight microscopic residual lesions (haemosiderin deposits) were seen three weeks after shockwave. In almost all instances, the lesions were detected by CT, MRI, and ultrasonography, while laboratory tests were negative.

Additional endoscopic procedures instead of urgent surgery for retained common bile duct stones

One hundred and twenty seven patients were treated by nasobiliary drainage, or stenting, to prevent biliary obstruction after endoscopic failure to clear stones from the common bile duct. At presentation, 91 (72%) patients were jaundiced and 39 (31%) had cholangitis. Placement of either a nasobiliary drain or stent was successful in 124 (98%) patients. One hundred and twenty one (95%) patients were followed up. Clearance was ultimately achieved endoscopically in 52 and surgically in 25 patients after (mean) 2.4 months. Thirty day mortality was 3%. There were no complications of nasobiliary drainage, but two of 39 patients treated by temporary stents developed cholangitis, both successfully managed by endoscopic duct clearance. Forty two patients unfit for surgery or further endoscopic attempts at duct clearance were followed with stents in situ for a mean 15.9 months (range 2.5-37.5). Cholangitis developed in four patients and was successfully managed by stent change. These results indicate that longterm stenting can be useful for poor risk surgical patients and that nasobiliary drainage or temporary stenting permits further elective rather than urgent endoscopic or surgical treatment.

Electrohydraulic lithotripsy for biliary stones

Electrohydraulic lithotripsy was applied in 10 patients with biliary stones which were difficult to extract with the use of choledochoscopy and basket. The difficulties encountered included large impacted stones in the Hartmann's pouch, intrahepatic ducts and lower end of common bile-duct, stones situated at the orifice of acutely angulated segmental bile-ducts and stones impacted just behind strictures. With the use of electrohydraulic lithotripsy all the stones were disintegrated and removed. The only complication was transient haemorrhage from ductal injury. It is concluded that electrohydraulic lithotripsy is a useful adjunct to the choledochoscopic removal of biliary stones.

Current state and future developments of noninvasive treatment of human urinary stones with extracorporeal shock wave lithotripsy

Extracorporeal shock wave lithotripsy has now been in clinical use for 8 years and it has replaced other treatment techniques for the majority of surgical calculi in the upper urinary tract. For the first time it provides a completely noninvasive method for the treatment of renal and ureteral stones. The current range of its indications includes approximately 70 per cent of nonselected urinary stone patients. An additional 25 per cent of the patients with more complex stones in the upper urinary tract can receive treatment with the lithotriptor combined with endourological procedures. More recent additions to the range of clinical routine applications with the original lithotriptor have been its use on common bile duct stones combined with endosurgical or radiological manipulations. With a modified kidney lithotriptor gallstones have been treated successfully, which has led to the development of a multipurpose device for biliary and urinary stones.

Selective ERCP and preoperative stone removal in bile duct surgery

This project was undertaken to evaluate in a prospective fashion the effects of selective preoperative endoscopic-retrograde cholangiography and stone extraction (ERCP-ST EXTR) on the results of biliary tract surgery. Over a 6-year period, 728 patients with primary or secondary biliary tract disease were admitted to the First Surgical Department, landeskrankenanstalten, Salzburg, Austria. If, based on preoperative screening, the possibility of common bile duct stones (CBDS) existed, the patients were subjected to ERCP-ST EXTR. Two to 4 days later, these patients underwent a simple cholecystectomy with intraoperative cholangiogram and functional manometry. Evaluation criteria for this study were morbidity, mortality, and retained stone (RST) rates. The overall complication rate for the entire series was 6%. In patients who underwent operative common duct stone removal (n = 78), the complication rate amounted to 21.8%. The rate was reduced to 2.1% by ERCP-ST EXTR. The RST rate was likewise reduced from 2.2% to 0.5% by ERCP-ST EXTR. Mortality in patients with CBDS fell from 3.8% to 1% through the use of this method. In those patients with secondary stones who were treated by ERCP-ST EXTR only, morbidity was 2%, the RST rate was 0%, and mortality was 0%. It is concluded that selective ERCP-ST EXTR, followed by simple cholecystectomy, is a suitable treatment protocol and that this approach may reduce complication and mortality rates.

A multivariate analysis of preoperative risk factors in patients with common bile duct stones. Implications for treatment

A multivariate analysis of 30 preoperative risk factors was undertaken in 248 patients who underwent surgery alone for common bile duct (CBD) stones and in 190 patients who had endoscopic sphincterotomy (ES), 77 of whom subsequently also had surgery. Independently significant risk factors in those undergoing surgery were the serum bilirubin level, the use of preoperative ES, and the presence of medical risk factors; in patients undergoing ES, only the serum bilirubin and albumin, but not medical risk factors, were of independent significance. The major implications of this study are, first, that high-risk patients should be treated by ES without subsequent surgery, and second, that "fit patients should be treated by surgery alone without routine preoperative ES.

Efficacy and safety of a combination of chenodeoxycholic acid and ursodeoxycholic acid for gallstone dissolution: a comparison with ursodeoxycholic acid alone

Chenodeoxycholic acid (CDC) and ursodeoxycholic acid (UDC) have distinct physicochemical and metabolic properties which, being complementary, should favor more rapid removal of cholesterol from gallstones when both bile acids are administered together. To see if the combination is more effective and well tolerated, we have compared 5 mg/kg of CDC plus 5 mg/kg of UDC with a 10-mg/kg dose of UDC alone in 120 patients with radiolucent, sonographically confirmed gallstones and characteristics favoring complete dissolution. Ursodeoxycholic acid was chosen as the reference because it dissolves stones faster and is better tolerated than CDC. To minimize the influence of stone size, the major determinant of dissolution, patients were divided, on admission, into two groups according to the maximum stone diameter: 50 had stones less than or equal to 5 mm, 70 had stones greater than 5 mm but less than 15 mm. The effects of treatment on stone dissolution evaluated by cholecystography and ultrasonography at 6, 12, and 24 mo, were analyzed by the actuarial life-table method. In the group with smaller stones, significantly more patients had obtained complete dissolution after treatment with the combination (52%) than after treatment with UDC alone (24%) at 6 mo. After longer periods, results were still better with the combination, although the differences from UDC alone became smaller. In the patients with larger stones, rates of complete and partial dissolutions were higher after treatment with the combination (51% vs. 24% with UDC) at 6 mo and again the differences had become smaller after longer treatment. Although not statistically significant, stone calcification occurred more often with UDC (7 cases) than with the combination (1 case). We conclude that CDC plus UDC is preferable to UDC alone because it dissolves stones more quickly, with a lower incidence of stone calcification, and may result in reduced cost of treatment.

Fragmentation of bile duct stones by extracorporeal shock waves. A new approach to biliary calculi after failure of routine endoscopic measures

A prospective uncontrolled multicenter trial was performed on 113 patients with bile duct stones in whom routine endoscopic approaches for removal of the calculi had failed. These represented 8.3% of the patients referred to the participating centers for endoscopic extraction of the stones. Extracorporeal shock-wave lithotripsy using the Dornier kidney lithotripter achieved stone disintegration in 103 patients (91%). Complete stone clearance from the bile ducts was obtained in 97 patients (86%) after a median of 4 days following extracorporeal shock-wave lithotripsy. Adverse effects, mostly mild, occurred in 36% of the patients. A 30-day mortality rate of 0.9% (in-hospital mortality rate = 1.8%) of this high-risk group with a mean age of 72 yr and a cholangitis rate of 26% compared favorably with the data given for open surgery. We therefore consider extracorporeal shock-wave lithotripsy a useful method for the treatment of bile duct stones not amenable to routine endoscopic measures.

Low-dose ursodeoxycholic acid prolongs cholesterol nucleation time in gallbladder bile of patients with cholesterol gallstones

The high rate of stone recurrence represents a drawback of non-surgical therapy of cholesterol gallstone disease. Although most studies report that long-term bile acid treatment does not have protective effects, preliminary results suggest that low-dose ursodeoxycholic acid decreases the rate of gallstone recurrence in a subgroup of younger patients. To clarify the underlying mechanism we investigated whether low-dose ursodeoxycholic acid treatment influences biliary cholesterol saturation and/or nucleation time of cholesterol. Ten patients with cholesterol gallstones and functioning gallbladder received 250 mg ursodeoxycholic acid/day at bedtime 6-10 days prior to cholecystectomy. Eleven patients with cholesterol gallstones without treatment served as controls. Cholesterol crystals were present in the gallbladder bile of 7 out of the 10 patients receiving ursodeoxycholic acid and in all control biles. Ursodeoxycholic acid treatment significantly (P less than 0.02) decreased the cholesterol saturation index (mean +/- S.E.: 0.94 +/- 0.05 vs. 1.43 +/- 0.18) and led to an approximately 5-fold prolongation (P less than 0.005) of the cholesterol nucleation time (mean +/- S.E.: 12.0 +/- 2.4 vs. 2.3 +/- 0.7 days). We conclude that low-dose ursodeoxycholic acid might be effective in the prevention of post-dissolution gallstone recurrence by both decreasing cholesterol saturation and prolonging cholesterol nucleation time.

Percutaneous cholecystolithotomy

We have successfully removed gallstones percutaneously from the gallbladders in two poor surgical risk patients using the standard equipment and the principles of percutaneous nephrolithotomy. No complication occurred in either patient. A brief review of percutaneous gallstone extraction is presented.

Percutaneous stone clearance of the gallbladder through an access cholecystostomy. Laparoscopic-guided technique

A laparoscopic-guided technique of percutaneous gallstone fragmentation/removal has been developed in the pig. The procedure entails the creation of a percutaneous access cholecystostomy. The access tract can be safely dilated after 7 days to F16, thereby allowing the introduction of both the Olympus flexible and the Berci-Shore rigid choledochoscopes. Following endoscopic occlusion of the cystic duct by a biliary balloon catheter, stone fragmentation can be conducted under direct visual control. In this particular study, electrohydraulic lithotripsy was performed of human cholesterol and bile-pigment stones inserted into the gallbladder of 16 pigs. The gallstone debris resulting from lithotripsy was then washed out with saline. Larger residual fragments could easily be extracted with the Dormia basket under visual guidance. There was a significant positive correlation between stone size (r = 0.98) and weight (r = 0.96) and the number of pulses needed to achieve satisfactory stone fragmentation. The gross composition of the stones (predominantly cholesterol or pigment) did not influence the number of pulses required. Electrohydraulic lithotripsy caused an explosion effect (the fragments hit the gallbladder wall), causing submucosal haematoma formation. This, however, was not followed by any untoward effect until sacrifice of the animals 10-16 weeks later. Electrohydraulic shocks delivered to the gallbladder wall itself resulted in larger haematoma formation and breach of the gallbladder mucosa with active bleeding into the gallbladder lumen, but again no instance of gallbladder perforation was encountered.(ABSTRACT TRUNCATED AT 250 WORDS)

Urinary extracorporeal shock wave lithotripsy: equipment, techniques, and overview

Second generation urinary lithotriptors are characterized by extensive technical alterations and significant equipment improvement in the functional, logistical, and medical aspects of shock wave lithotripsy (SWL). These newer devices feature a water bath-free environment, a reduced anesthesia requirement, improved imaging, functional uses in addition to lithotripsy, or combinations thereof. Shock wave generation by spark gap, electromagnetic, piezoelectric and microexplosive techniques are related to their peak energy, frequency, and total energy capabilities which impacts on both anesthesia needs and the length and number of treatment sessions required to pulverize calculi. A master table summarizes the types of SW energy, coupling, imaging systems, patient transport, functional features, cost, and treatment effectiveness of 12 worldwide lithotriptors in various stages of investigative and clinical trials as monitored by the Food and Drug Administration (FDA) of America.

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.

Changing surgical aspects of urinary stone disease

Surgical management of urinary calculous disease has changed dramatically in the past decade. The development of percutaneous nephrostomy techniques has allowed new access to upper tract stones. Percutaneous removal of large calculi was made possible by the development of ultrasonic and electrohydraulic lithotripsy. All upper tract calculi can now be removed in 70 to 100 per cent of cases with minimal complications. Nephrostolithotomy has reduced transfusion rates and hospitalization costs and has markedly shortened convalescence periods compared with open surgery. Ureteroscopy followed nephrostolithotomy as advanced fiberoptic technology allowed the development of the small-caliber instruments required for this procedure. With experience, successful stone retrieval has occurred in 90 per cent or more of cases, again with minimal complications. As nephrostolithotomy and ureteroscopy have become available, the subspecialty of endourology has emerged and significantly changed the management of urinary tract calculi. Perhaps the most significant advance in stone therapy has been the design and implementation of extracorporeal shock wave lithotripsy. With this noninvasive technique, most renal and proximal ureteral calculi can be effectively treated with minimal morbidity and convalescence. Research in lithotripter design is continuing, with more advanced and effective machines on the horizon. The applicability of extracorporeal therapy for the treatment of biliary tract calculi is currently under investigation. Finally, one should not disparage medical therapy for recurrent nephrolithiasis. A comprehensive metabolic evaluation combined with selective medical therapy provides almost complete relief from recurrent stone formation and makes medical therapy an integral component of treating the patient with renal or ureteral calculi.

Cholesterol and pigment gallstone disease: comparison of the reliability of three bile tests for differentiation between the two stone types

Gallbladder biles and stones were obtained at 116 cholecystectomies for symptomatic gallstone disease. All 33 patients younger than 50 years had cholesterol stones, whereas 40% of the older patients had pigment stones. We compared the reliability of three different bile tests for the differentiation between cholesterol and pigment stone patients. Whereas both the presence of cholesterol monohydrate crystals in fresh gallbladder bile and a nucleation time less than or equal to 20 days in ultrafiltered gallbladder bile had a specificity of 100% for cholesterol gallstone disease, biliary supersaturation with cholesterol (cholesterol saturation index greater than 1.0) had a low specificity. The sensitivity of nucleation time less than or equal to 20 days for cholesterol gallstone disease was 78% in concentrated gallbladder biles (biliary total lipid concentration greater than or equal to 5 g/dl) but only 21% in dilute biles (biliary total lipid concentration less than 5 g/dl). In contrast, examination for the presence of cholesterol crystals in fresh bile was reasonably sensitive both in concentrated and dilute gallbladder biles (sensitivity, 84% and 72%, respectively). In addition, duodenal bile obtained from 16 patients (10 cholesterol, 6 pigment) before cholecystectomy showed cholesterol crystals in 7 of the cholesterol but in none of the pigment stone patients. We conclude that examination of fresh bile for cholesterol crystals is a specific and reasonably sensitive test for cholesterol gallstone disease.

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.

Fragmentation of gallstones using extracorporeal shock waves: an in vitro study

Eighty in vitro experiments were performed with single (n = 51) or multiple (n = 29) gallstones in order to find out which parameters are of prime importance for their disintegration by extracorporeal shock waves. A Dornier lithotripter and an upper limit of 1,500 discharges were employed. Although computed tomography density was significantly lower in cholesterol stones than in the noncholesterol stones (p less than 0.0001) and although the latter were significantly more often radiopaque (p less than 0.0001), we found no clear-cut correlation between the cholesterol content or computed tomography density and the degree of fragmentation of the stones. The most important variable which limited successful disintegration was the total stone volume. In stones with a mean total volume of 0.83 ml +/- 0.25 S.E. (diameter for single stones = 11.5 +/- 0.9 mm), none of the fragments exceeded 2 mm, whereas in stones with a mean volume of 3.6 ml +/- 0.64 (diameter = 17.2 +/- 1.5 mm) at least one fragment larger than 2 mm remained (p less than 0.002). Under the in vitro conditions, fragmentation was similar in multiple and solitary stones, provided the volume of the stones was comparable. These data show that, in general, the number and size of the stones, i.e. their total volume, and much less significantly their chemical composition are the major determinants of fragmentation by extracorporeal shock waves.

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.

Piezo-ceramic lithotripsy of gallbladder stones: initial experience in 38 patients

The efficacy, safety, and side-effects of a piezo-ceramic system for extracorporeal shock-wave lithotripsy of gallbladder stones were assessed in the first 38 patients treated. Gallstone fragmentation was achieved in 34 patients; 25 required more than 1 treatment session (range 1-5). Extracorporeal shock-wave lithotripsy, conducted without sedation, analgesia, or anaesthesia, was well tolerated by all patients; no patient reported pain or discomfort either during or after the procedure. Side-effects were negligible: transient microscopic haematuria in 2 patients, transiently abnormal liver function tests in 1, and short-lived cutaneous petechiae in 4. Initial experience shows that lithotripsy with this system is effective, safe, and well tolerated.

Extracorporeal shock-wave lithotripsy and the management of common bile-duct calculi

Endoscopic sphincterotomy is the treatment of first choice for stones that remain in the bile duct after cholecystectomy. There is a small group of patients in whom this technique is not successful; many of these patients carry a high risk for surgery because of their age or associated medical conditions. A variety of non-surgical techniques is available; however, none is well established. We have used an in-vitro model to show that human gallstones are fragmented readily by shock-wave lithotripsy. Two elderly frail patients with difficult bile-duct stones have been treated successfully by extracorporeal shock-wave lithotripsy. The bile ducts were cleared of stones and the patients suffered no adverse effects. Extracorporeal shock-wave lithotripsy is a new and promising alternative to the current non-surgical techniques for the management of bile-duct stones.

Laserlithotripsy of common bile duct stones

Endoscopic retrograde laser lithotripsy of common bile duct stones is a new technique which can be carried out through the endoscope without anaesthesia using ordinary endoscopic equipment. In the method described here a flashlamp pulsed Neodymium YAG laser (wave length 1064 nm) was used. Light energy was transmitted along a highly flexible quartz fibre with a diameter of 0.2 mm. This new technique was used in nine patients with concrements in the common bile duct, which could not be removed with the established endoscopic techniques. In eight of the nine the concrements (maximum diameter 4.7 x 3.1 cm) could be fragmented and in six the fragments could be extracted from the common bile duct. The total energy required was 80-300 J; complications were not observed.

Extracorporeal shock-wave lithotripsy (ESWL). II. In vivo canine results of blast path treatment of human gallstones

To evaluate the role of ESWL in vivo for the treatment of human gallstones positioned on the blast path, a canine model was developed to determine the efficacy of stone fragmentation and the subsequent histopathological injury that occurs as a result of this therapeutic technique. Twenty-four 16- to 20-kg mongrel dogs were divided into five groups: I: ESWL without stone, autopsy at 48 hr (N = 6); II: ESWL with stone (mean diameter 16.8 mm, range = 14-19 mm), autopsy at 48 hr (N = 10); III: ESWL without stone, autopsy at 41-46 days (N = 6); IV: ESWL without stone, autopsy immediately after ESWL (N = 1); V: No ESWL or stone, autopsy 2 hr after anesthesia induction (N = 1). A human gallstone (96% cholesterol) was inserted by cholecystotomy (N = 10) in Group II only. All groups (N = 24) had operative placement of a 6.5 Fr accordion catheter into the gallbladder for radiographic visualization. For each blast path treatment, 2000 discharges were delivered at 18-24 kV. Histopathologically, the Group V gallbladder served as a control. Groups I, II, and IV revealed mild subacute injury; dog gallbladders in Group III showed regression of these changes. Total surface area (TSA) of Group II stones increased from a pre-ESWL mean of 6.60 +/- 0.0.84 cm2 to 53.84 +/- 26.8 cm2 post-ESWL (P less than 0.001). Cumulative post-ESWL fragment sizes for particles in less than or equal to 2-, less than or equal to 3-, less than or equal to 5-, less than 10- and greater than or equal to 10-mm categories represented 32.9, 41.6, 49.4, 74.3, and 100% of pretreatment stone weight, respectively. These data indicate that human gallstones can be fractured to a variable degree when treated on the ESWL blast path and that TSA increased significantly. Gallbladder histopathologic changes appear to be reversible by 41-46 days post-ESWL.

Human amnion as a bioprosthesis for bile duct reconstruction in the pig

Despite technical advances in management, the complication of late stricture formation and biliary sepsis still occur in bile duct reconstruction. In an attempt to avoid bilioenteric anastomosis, which bypasses the biliary sphincter mechanism, various biologic and artificial materials have been employed clinically and experimentally to replace the damaged bile duct. No satisfactory biliary replacement material has yet been found. In the experimental model of bile duct stricture that has been presented, human amnion bile duct injuries mimicking those seen in clinical practice were repaired using human amnion as a free graft. Noncircumferential duct loss appeared to be satisfactorily repaired using amnion, and the amnion repair was found to be as good as or superior to plastic repair; however, circumferential duct loss was not adequately repaired with the amnion graft.