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PubMed1986

Extracorporeal shock-wave lithotripsy for upper urinary tract calculi. One year's experience at a single center.

Four hundred sixty-seven patients with symptomatic upper urinary tract calculi underwent extracorporeal shock-wave lithotripsy (ESWL) at The New York Hospital-Cornell Medical Center during the first year. Ninety-five percent of stones were completely treated with one ESWL session. An analysis of 300 treatments revealed that the overall stone-free rate (success) three months after treatment was 75%. The stone-free rate for patients with renal pelvic calculi less than or equal to 20 mm in diameter was 91%. Individual patient stone-free rates depended on stone size (burden), position, composition, and quality of disintegration. Two percent of treatments failed to disintegrate the targeted stone. Complications were minimal. Seven percent of treatments were followed by a secondary endoscopic procedure to facilitate complete stone passage, and 23% of treatments were preceded by cystoscopy with ureteral stent placement of manipulation of stones. Combined therapy utilizing percutaneous surgery or multiple sequential ESWL treatments is necessary for complex stones, and ureteroscopy or basket extraction remains the treatment of choice for distal ureteral calculi.

Adolescent↗
PubMedDate not supplied

In vitro destruction of urinary calculi by laser-induced stress waves.

A new, nonsurgical technique is proposed for the destruction of urinary calculi. This technique exploits recent advances in laser-fusion research in the generation of shock waves from high-intensity pulsed lasers and the principles evolved from extensive military research on fragmentation resulting from the interactions of shock waves on solids. In the in vitro experiments reported here, stress waves were generated by irradiating a thin film confined between glass and metal substrates with a high-intensity pulsed laser. It was shown that a nominal 2-J, Q-switched Ruby or Nd-glass laser is easily capable of producing stress waves of up to 10-kbar peak pressure and that the rise time of the stress pulse is on the order of the laser pulse duration. Urinary calculi (kidney or bladder stones) of different sizes, shapes, colors, hardnesses, and composition were fragmented by laser-induced shock waves into sizes quite capable of being passed spontaneously. Critical laser parameters have been determined, and the associated threshold pressure for the destruction of the hardest types of urinary stones has been measured. The possible application of this technique to in situ destruction of urinary calculi is described.

Acoustics↗
PubMed1994

[Clinical application of a third generation lithotripter (Modulith SL20) for urinary tract calculi].

A third generation lithotripter (Modulith SL20) was used for disintegration of upper urinary tract calculi. From April 1991 through March 1993, a total of 281 sessions were carried out on 212 patients with upper urinary tract calculi at Seichoukai Fuchu Hospital. One month after the last session, of the 141 patients evaluated, 55 (39.0%) were free from stone fragments and 52 (36.9%) had stone fragments equal to or smaller than 4 mm. The over-all successful rate was 75.9% and the success rate was excellent for lower ureteral stones. As side effects, there were no serious complications other than perinephritic hematoma which occurred in 2 patients. These findings clearly indicated that the Modulith SL20 lithotripter was highly useful for disintegration of calculi of the upper urinary tract.

Adult↗
PubMed1995

[Urinary calculi, consisting of dehydrated calcium phosphate. Clinical, biological, radiologic aspects, clinical course and management].

Seventeen cases of urinary calculi analyzed by infrared spectrophotometry were found to be composed entirely or nearly entirely of bihydrated calcium hydrophosphate. The observations are summarized here. This type of stone occurs with a frequency of about 1% (0.85% in our experience) of all urinary calculi, predominantly in men (14 of our 17 cases). Diagnosis is based on the physical and chemical analysis of the stone and on infrared spectrophotometry. Most of these stones are pure or nearly pure compounds. The macroscopic aspect of the stones or fragments of stones can guide diagnosis. These stones are cream coloured stones with a smooth regular outer surface. Broken fragments show the same cream colour, sometimes with strips radiating from the centre of the fracture surface. Radiologically, these stones are homogeneously radio-opaque, often oval-shaped with a regular outline. Blood tests can demonstrate suspected or proven hyperparathyroidism (4 out of 10 cases in our 17 observations) with hypercalcemia, hypophosphatemia and hypercalciuria. Complementary examinations may be needed to search for a parathyroid adenoma. With or without hyperparathyroidism, 24-h urinalysis usually shows hypercalciuria up to ro over 500 to 600 mg/24 h. Crystallization usually occurs in the upper urinary tract, in the bladder or in indwelling catheters. These stones are extremely hard and are difficult to break in vitro. To be successful, lithotripsy requires prolonged treatment: up to 3000 to 6000 shockwaves at 22-23 kv with the Dornier apparatus. Despite the notion of hypercalciuria, the pathogenesis of bihydrated calcium hydrophosphate calculi remains to be elucidated.

Adult↗
PubMed1987

Measurement of the optical and thermal properties of biliary calculi using pulsed photothermal radiometry.

The optical absorption coefficients for biliary calculi are important in understanding the mechanism of laser-induced stone fragmentation. However, the heterogeneous composition of calculi and difficulties in producing optically thin samples prevent conventional spectrophotometric measurement techniques from being used. To overcome these limitations, we used a pulsed photothermal radiometry system to measure the optical absorption coefficients and thermal diffusivities of various biliary calculi. In the wavelength range examined (350-1,060 nm), there was strong optical absorption which was greater for pigment stones than for cholesterol stones. The data support the theory that the initiation of the plasma accompanying laser fragmentation of calculi is a thermal process.

Absorption↗
PubMedDate not supplied

Limitations of percutaneous transhepatic cholangioscopy in the removal of complicated biliary calculi.

To investigate the limitations of percutaneous transhepatic cholangioscopic lithotomy (PTCSL) in the management of retained or reformed biliary calculi, we conducted a retrospective study of 50 patients who had received PTCSL for complicated biliary calculi during a period of 32 months. The calculi were located in the common bile duct (24%), the intrahepatic bile ducts (60%), and in both the common bile duct and intrahepatic bile ducts (16%). The adjunctive techniques in PTCSL included balloon dilatation for the biliary stricture, electrohydraulic lithotripsy (EHL) for crushing large impacted stones, and flushing techniques, biliary spoons, and basket catheters for stone fragmentation and grasping. The overall percutaneous manipulations totaled 221 procedures, including 124 sessions of PTCS. In each patient, the number of sessions of PTCS varied from 1 to 7. In our series, the main complications of PTCS therapy, rarely reported in the literature, included pain intolerance in 7 cases (14%), minor bleeding in 7 cases (14%), and massive bleeding which needed angiographic diagnosis and therapy for hemostasis in 5 cases (10%). Secondary biliary cirrhosis, severe biliary stricture and angulations, previous shunt surgery, neovascularization surrounding the chronic inflammatory stenotic intrahepatic bile ducts, pseudoaneurysm formation, and coexistent cholangiocarcinoma contributed to the vulnerability of bleeding during manipulations. The complications resulted in treatment failure in 11 patients (22%). We conclude that PTCS is a useful alternative treatment to surgery for biliary calculi, but it has limitations that obviate complete stone clearance.

Adult↗
PubMedDate not supplied

Fragmentation of biliary calculi in 71 patients by use of intracorporeal electrohydraulic lithotripsy.

PURPOSE: Failure of percutaneous or endoscopic removal of biliary calculi is often associated with impacted stones or stones larger than 1.5 cm. In these difficult cases, intracorporeal electrohydraulic lithotripsy (EHL) is a method that allows large stones to be fragmented and removed percutaneously or endoscopically. In this study, the authors expand their experience with EHL and further evaluate the safety and efficacy of this technique to remove biliary tract calculi. PATIENTS AND METHODS: Intracorporeal electrohydraulic lithotripsy was used to treat 71 patients with calculi in the bile ducts (n = 35) or gallbladder (n = 36). Access was obtained by means of a surgical T-tube tract (n = 16), percutaneous transhepatic biliary drainage (n = 14), percutaneous cholecystostomy (n = 36), an intraoperative approach during common duct exploration (n = 2), and at endoscopic retrograde cholangiopancreatography (n = 3). RESULTS: EHL lithotripsy was effective in fragmenting all biliary stones in 69 of the 71 patients (97%). All of the stone fragments were removed in 67 of these 69 patients (94%). Major complications, including bile peritonitis and gallbladder necrosis, occurred in five patients; however, all major complications were related to the initial percutaneous drainage or tract dilation. No significant complications were directly attributable to the EHL procedure. CONCLUSION: Intracorporeal EHL is a safe and effective method that can be used to improve the success of percutaneous and endoscopic biliary calculi removal.

Adult↗
PubMed2000

Gallstones and common bile duct calculi in infancy and childhood.

BACKGROUND: Gallstones and common bile duct calculi have been increasingly diagnosed in recent years in infants and children. The present study aims to review the spectrum of this disorder in the last two decades. METHODS: During the period 1979-96 a total of 102 consecutive infants and children were diagnosed in Royal Alexandra Hospital for Children with gallstones or common bile duct calculi. A detailed retrospective analysis and follow-up of these children form the basis of the present report. RESULTS: The median age at presentation was 10 years. Recurrent right upper quadrant pain was the most common clinical presentation. The male-to-female ratio was 3:2 and this male predominance was noted in all the age groups. Aetiologically three identifiable groupings were noted: idiopathic disease (n = 66), haematological diseases (n = 23) and specific non-haematological disease (n = 13). The incidence of idiopathic and haematological stones had increased two-fold in the second half of the study. The majority of children (86%) underwent surgical correction. Choledocholithiasis (CDL) was noted in 18 children (18%). Jaundice was commonly associated with abdominal pain in this group. A higher incidence of common bile duct calculi was noted in females and children less than 5 years of age (P < 0.01). Common bile duct calculi were accurately diagnosed by pre-operative imaging in all 18 children. Surgical correction was required in all except two. CONCLUSIONS: The present study suggests an increasing incidence of gallstones in children. Cholelithiasis in children occurs commonly in boys, is idiopathic in aetiology and presents with a vague right upper quadrant pain. Choledocholithiasis is not uncommon in children, occurs more commonly in girls aged < 5 years and presents with jaundice or abnormal liver function tests.

Adolescent↗
PubMed1984

Common bile duct calculi. 1. Surgical therapy.

Multiple techniques are now available for management of the patient with retained or recurrent common bile duct calculi. The goal of treatment is extraction of calculi with the lowest possible incidence of morbidity and mortality, the lowest cost and least discomfort to the patient, and the best long-term results. The choice of therapy--surgical or nonsurgical--depends on several factors, including presence or absence of the gallbladder and a T tube, type of calculi, operative risk, accompanying conditions, and expertise available at a particular institution. The decision to explore the common bile duct at the time of elective cholecystectomy is based on clinical, operative, and cholangiographic information. A rigorous technique of surgical exploration that includes duodenal mobilization, choledochoscopy, and cholangiography is necessary. In selected patients, biliary enteric anastomosis decreases the incidence of retained or recurrent calculi.

Alkaline Phosphatase↗
PubMed1980

Differentiation of acoustic shadowing due to calculi and gas collections.

In abdominal sonography, acoustic shadowing may be seen distal either to calculi or gas collections. This in vitro study suggests that acoustic shadows distal to calculi contain significantly fewer echoes, and are therefore more sharply defined than those distal to gas collections. Artifactual reverberation echoes within acoustic shadows distal to gas collections result from virtually total sound reflection at tissue-air interfaces, whereas shadows distal to calculi are primarily due to sound absorption. The appearances of shadowing distal to calculi or gas collections may be of value in clinical sonography.

Abdomen↗
PubMed1985

Sonographic and computed tomographic evaluation of intrahepatic calculi.

Intrahepatic calculi in non-Asian patients were studied by sonography and computed tomography (CT). Three patients were studied by CT cholangiography also. In two cases, the calculi were consecutive to Caroli disease, and in two others, the biliary stones were formed proximal to a stenosis of a previous surgical anastomosis. Five patients spontaneously developed intrahepatic calculi. All sonograms were abnormal. Image specificity was good, even when bile ducts were not dilated, if appropriate technique allowed identification of a double-arc-shadow pattern. Sonography strongly suggested the diagnosis in eight patients and was nonspecific in only one. On CT, calculi had various densities, and they were not visible in two patients. CT cholangiography was not particularly helpful. Finally, CT added little more information when performed after sonography. Both examinations strongly underestimate the number of stones, and direct cholangiography remains indicated if surgery is planned.

Adult↗
PubMed1982

The composition of biliary calculi in patients with juxtapapillary duodenal diverticula.

Biliar calculi from 32 patients with juxtapapillary duodenal diverticula were analyzed by quantitative infrared spectroscopy. In 22 of the patients the calculi were classified as pigment stones and in 10 as cholesterol stones. Calcium bilirubinate was the main component in the pigment stones, with a median value of 45%; the median cholesterol content was 7.5%. In the cholesterol stones median calcium bilirubinate content was 1% and median cholesterol content 95.5%. Calcium carbonate was found in small amounts in only nine of the calculi. The findings support our theory that the pigment calculi in patients with juxtapapillary diverticula are caused by ascending infections to the bile ducts with intestinal beta-glucuronidase-producing bacteria. Beta-glucuronidase will split the conjugated bilirubin in bile into glucuronic acid and unconjugated bilirubin, which in turn combine with calcium to form insoluble calcium bilirubinate.

Adult↗
PubMed1996

Endoscopic treatment of bile duct calculi in patients with gallbladder in situ: long-term outcome and factors.

BACKGROUND: Whether endoscopic sphincterotomy (EST) in elderly and/or high-risk patients with common bile duct calculi (CBD) and the gallbladder in situ should be followed by routine cholecystectomy is still a subject of controversy. METHODS: To identify factors predictive of subsequent biliary tract symptoms after EST and bile duct clearance, we reviewed 265 patients with intact gallbladder and CBD calculi who were considered for EST in our department from 1981 to 1992. In 15 of 265 patients endoscopic treatment was not carried out, and the records of 4 patients were missing. RESULTS: Complete removal of all bile duct calculi failed in 27 patients (11%). Cholecystectomy was performed in 35 patients (16%) with cleared bile ducts 1-765 days (median, 60 days) after EST, in spite of absence of recurrent symptoms from the biliary tract. The remaining 184 patients have been retrospectively followed up for 14-150 months (median, 69 months). Cholecystectomy was required in 35 because of acute cholecystitis (n = 23) or biliary colic (n = 12). Of the cholecystectomies 86% were performed within 24 months after EST and only one after 4 years of follow-up. Increased frequency of cholecystectomy was found in patients with complete opacification of the gallbladder at endoscopic cholangiography (p = 0.005). This was especially evident in patients younger than 80 years (p = 0.002). Cholecystectomy was also required more often in patients with gallbladder calculi (p = 0.02). The risk of cholangitis in patients without recurrent stones was higher in those with juxtapapillary diverticula (p = 0.02). Fifty-nine patients without and 17 with mild to moderate symptoms from the biliary tract died after a median time of 39 and 46 months, respectively. Seventy-three patients are alive, and 59 are symptom-free. Ten patients have had and four still have complaints of mild to moderate biliary tract symptoms. They have been followed for up to 16-146 months (median, 40 months). CONCLUSIONS: These findings confirm that endoscopic treatment alone in this group of patients is a feasible treatment principle. Recognition of the registered risk factors might be helpful when selecting patients for subsequent cholecystectomy.

Aged↗
PubMed2002

Correlation between chemical composition of biliary calculi and sera of stone formers.

A quantitative chemical analysis of total cholesterol, bilirubin, calcium, inorganic phosphate and iron of three types of biliary calculi (cholesterol, pigment and mixed) of 40 gall stone former was carried out and correlated to with those of there sera. A moderately positive correlation for inorganic phosphate, Ca2+ and Fe2+ content of sera and calculi of cholesterol stone patient was found. A Good positive correlation for total cholesterol, a moderately positive correlation for bilirubin and iron but no correlation for inorganic phosphate and calcium content of sera and calculi of pigment stone patient was observed. A good moderately positive correlation for iron but no correlation for total cholesterol, bilirubin, inorganic phosphate and Ca2+ content of sera and calculi of stone patient was found.

Bilirubin↗
PubMed1990

Electromagnetic shock-wave lithotripsy of gallbladder calculi. Multicentered preliminary report on experience with 276 patients.

The Lithostar Working Group reports on the first 276 patients who underwent lithotripsy of biliary calculi by means of an electromagnetic Lithotriptor (Lithostar Plus from Siemens). Some 66% (183/276) and 27% (75/276) of the patients had solitary and two or three stones, respectively while 7% (18/276) had more than three gallbladder calculi. Calcified calculi were found in 11% of the patients. On an average the patients were treated in 1.6 (range 1.4-2.15) sessions; with the exception of one user the maximal energy (setting 9) was applied. The upper limit of shock waves per session was 1500-6000 (x = 2189 +/- 1058). 17% and 48% of the patients were free from calculi after 3 and 6 months, respectively. During the follow-up period 14% of the patients complained of severe biliary pain and 1.5% suffered from pancreatitis, which was controlled by conservative treatment. In three out of five patients with a transitory cholestatic jaundice endoscopic papillotomy was necessary. Four patients underwent an elective cholecystectomy. Considering the selection of the patients, the results obtained are comparable with those found in other studies.

Cholelithiasis↗
PubMed1971

The prevention of residual biliary calculi.

Residual calculi following cholecystectomy may be expected in approximately seven percent of cases. The vast majority of these are overlooked during operation; truly re-formed stones are rare. Calculi are missed during cholecystectomy because of failure to explore the common bile duct. This is due to (1) the presence of silent choledochal stones, and (2) reliance on negative cystic duct cholangiograms in the presence of indications for common duct exploration. Overlooking of silent stones during cholecystectomy may be prevented by routine operative cholangiography. Ideally, false-negative cystic duct cholangiograms should be eliminated by the use of fluoroscopic cholangiography. Retained calculi following duct exploration may be prevented by (a) routine biliary endoscopy and (b) completion fluoroscopic cholangiography.Re-formation of ductal calculi can probably be prevented by appropriate biliary drainage procedures performed during the initial choledochotomy. Selection of patients for primary biliary decompression remains an experimental problem.

Cholecystectomy↗
PubMed1981

Duodenal diverticula and their relationship to age, sex, and biliary calculi.

The relationship between duodenal diverticula and age, sex, and biliary calculi was studied prospectively in 624 patients examines with endoscopic retrograde cholangiopancreatography (ERCP). The study showed that the incidence of biliary calculi was significantly higher in patients with diverticula (86%) than in patients without diverticula (38%). The difference was significant in all age groups above 40 years (p less than 0.01). The rate of diverticula found near the papilla of Vater was significantly higher in patients with biliary calculi than in patients without (p less than 0.01). A positive correlation was found between age and diverticula but not between sex and diverticula. An insufficient papillary sphincter together with an ascending bacterial infection is discussed as a possible explanation for the higher incidence of biliary calculi in patients with duodenal diverticula.

Adult↗
PubMedDate not supplied

[Role of radiographic signs of urinary calculi in the effectiveness of extracorporeal shock-wave lithotripsy].

The value of X-ray signs of urinary calculi for the efficiency of shock-wave teletripsy (SWTL) was assessed in 188 patients with nephro-ureterolithiasis. The calculi were studied from the general X-ray film by means of a routine 4-5x magnifier. All the patients were divided into 2 groups. Group 1 comprised patients with effective SWTL, i.e. those undergone 1 or rarely 2 sessions. Group 2 included those with low effective SWTL, 2-4 sessions. Comparative analysis of X-ray films indicated that the calculi which were homogeneous in structure, moderate in intensity and had even edges in the general X-ray pictures in 154 (82%) cases were fragmented after 3-4 sessions (the average number of impulses were 7500, at 19.0 kV). With their heterogeneous structure, low and high intensity, irregular rough edges, they were fragmented after 1 or rarely 2 sessions in 34 (18%) patients. The number of impulses was fewer, on an average of 2300, the voltage was less -17.5 kV. It was noted that the pattern of the edges of a calculus and its geometric form are of highly value in the prediction of SWTL. Calculi having even edges were more frequently encountered in patients from Group 2 (in 81.1% of cases), but in patients of Group 1 they were only in 18.1%.

Adult↗