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PubMed1991

Percutaneous endoscopic laser lithotripsy of a cystic duct stone: a case report.

A case report of an elderly patient with severe heart disease and chronic obstructive pulmonary disease who required laser lithotripsy for a retained cystic duct stone is presented. This high-risk patient underwent a laparoscopic cholecystostomy and gallstone removal as treatment for symptomatic gallstone disease. On cholecystography the patient was found to have a small stone fragment in the cystic duct. Under intravenous sedation this stone fragment was fragmented and removed using an 8.5F flexible ureteroscope and a coumarin pulsed-dye laser lithotriptor. The stone was fragmented and washed into the common bile duct. Follow-up cholecystogram prior to removal of the cholecystostomy tube demonstrated no stones in the gallbladder, cystic duct, or common bile duct. The management of percutaneous removal of retained stones is reviewed.

Aged↗
PubMed1995

[Laser lithotripsy of refractory bile duct calculi after failure of extracorporeal shock wave treatment].

UNLABELLED: After failure of extracorporeal shockwave lithotripsy (ESWL) the benefit of further nonsurgical methods for treatment of difficult bile duct stones is undetermined. Endoscopic laserlithotripsy is a promising procedure providing target application of high energy levels. METHOD: Twenty patients (median age: 81 [67-91] years) were referred for laserlithotripsy of 1-8 (median, 2) difficult bile duct stones after failure of 1-4 (median, 3) ESWL sessions. The median diameter of each of the largest stone was 22 (10-48) mm. The laser used was a pulsed rhodamine laser (wavelength: 594 nm) with an automatic cut-out system upon no stone contact. The laser fiber was positioned by means of ERCP under fluoroscopic control or by use of mini-cholangio-scopes. Laserlithotripsy was cholangioscopically performed via the percutaneous transhepatic route in 8 patients because of retrogradely inaccessible bile ducts (n = 5) or because further ERCP was refused (n = 3). All procedures were carried out under intravenous sedation and/or analgesia. RESULTS: Laser lithotripsy and complete removal of fragments was achieved in 19 of the 20 patients after application of 70-25700 (median, 3310) pulses in 1.2 sessions per patient. Median duration of a single session was 70 (15-140) minutes. The procedure failed in one patient with an impacted stone at the cystic duct confluence. Cholangitis could be conservatively managed in 2 cases. No further complication was observed. The 30-day mortality rate was 0 %. CONCLUSION: Endoscopic laserlithotripsy is an effective, a rapid and safe procedure for bile duct stones even after failure of ESWL. The results compare favorably with open surgery, particularly in view of an increased risk in a group of elderly patients.

Aged↗
PubMed2006

Dependence of calculus retropulsion on pulse duration during Ho: YAG laser lithotripsy.

BACKGROUND AND OBJECTIVES: The purpose of this study was to investigate the effect of optical pulse duration on stone retropulsion during Ho:YAG (lambda = 2.12 microm) laser lithotripsy. STUDY DESIGN/MATERIALS AND METHODS: A clinical Ho:YAG laser with pulse durations was employed to fragment calculus phantoms and to evaluate stone phantom retropulsion. At a given pulse energy, optical pulse durations were divided into two discrete conditions: short pulse (tau(p): 120 to approximately 190 microseconds at FWHM) and long pulse (tau(p): 210 to approximately 350 microseconds at FWHM). Plaster of Paris calculus phantoms were ablated at different energy levels using optical fibers of varying diameters (273, 365, and 550 microm in core size). The dynamics of the recoil action of a calculus phantom was monitored using a high-speed camera; the laser-induced craters were evaluated with optical coherent tomography (OCT). Bubble formation and collapse were recorded with a fast flash photography setup, and acoustic transients were measured with a hydrophone. RESULTS: Shorter pulse durations produced more stone retropulsion than longer pulses at any given pulse energy. Regardless of pulse duration, higher pulse energy and larger fibers resulted in larger ablation volume and retropulsion (P<0.05). For shorter pulse durations, more rapid bubble expansion was observed and higher amplitudes of the collapse pressure wave were measured (P<0.05). CONCLUSION: Less retropulsion and equivalent fragmentation occurred when Ho:YAG pulse duration increased.

Analysis of Variance↗
PubMed1997

[Percutaneous and transpapillary laser lithotripsy of intrahepatic gallstones].

PROBLEM AND OBJECTIVE: In the last few years several intra- and extracorporeal endoscopic methods have been developed for treating intrahepatic gallstones, but as yet no ideal instrumentation has been found. This study was undertaken to test the efficacy and possible complications of intracorporeal laser lithotripsy for intrahepatic gallstones. PATIENTS AND METHODS: 16 consecutive patients were included (13 women and 3 men, median age 64 [28-82] years) with intrahepatic biliary tract stones which could not be removed by conventional endoscopy. A rhodamine-6G-laser with an integrated stone recognition system was used. The glass fibres of the laser instrument were introduced perorally or percutaneously and placed at the stone. RESULTS: The percutaneous procedure under cholangioscopic control succeeded in four of the patients, while 12 were treated by a transpapillary approach (two under fluoroscopic, ten under cholangioscopic control). In eight of the latter group all stones were completely fragmented, i.e. 12 of the total were successfully treated. Of the remaining four patients two were cleared of stone by additional measures (extracorporeal shockwave lithotripsy and electrohydraulic lithotripsy, respectively), two were treated pallatively by endoprosthesis. One patient developed an acute cholangitis which was successfully treated with antibiotics and biliary drainage. There were no deaths. CONCLUSIONS: Particularly when performed transcutaneously, laser lithotripsy provides effective treatment of intrahepatic gall stones. Cholangioscopic monitoring, to place the glass fibre at the stone, is usually required in the transpapillary approach.

Adult↗
PubMed2005

Successful treatment of Bouveret syndrome using holmium: YAG laser lithotripsy.

Although gallstone disease is highly prevalent, cholelithiasis causing gallstone ileus is uncommon. Consideration has been given for nonoperative strategies to resolve obstruction due to the significant age and comorbidities afflicting this population. A 94-year-old man presented with a 5-day history of abdominal distension and tenderness. CT scan revealed multiple large gallstones within the gallbladder, pneumobilia, and two ectopic gallstones (antrum of the stomach and distal ileum). The patient was taken to the operating room where an enterolithotomy and gastrotomy was performed with removal of gallstones and subsequent relief of obstruction. During the postoperative course, the patient developed symptoms of gastric outlet obstruction and underwent gastrointestinal endoscopy for diagnosis and treatment. Two large gallstones, present in the duodenum, were retracted into the stomach using a Roth net but could not be retrieved beyond the upper esophageal sphincter. A holmium: yttrium-aluminum-garnet (Holmium: YAG) laser was used for fragmentation of the stones, with subsequent successful removal. This is the first documented successful use of the holmium: YAG laser for the treatment of recurrent gallstone ileus. Physicians should remember that in a small but important subgroup of patients, endoscopy accompanied by laser lithotripsy may prove beneficial.

Aged, 80 and over↗
PubMed1993

Laser lithotripsy with the Candela MDL-2000 LaserTripter.

The Yorkshire Lithotriptor Centre acquired a Candela MDL-2000 LaserTripter and a 7.2F Miniscope in February 1990. We present the results obtained in the first 200 patients referred for treatment of ureteric stones or stone fragments. Of 175 patients who were evaluable, 58 had upper ureteric stones, 41 mid-ureteric and 76 lower ureteric stones. Successful laser fragmentation was achieved in 77% of cases and a further 10% were rendered stone-free by the push-bang technique. Ureterolithotomy was required in 9% and the major complication rate was 4%. Ureteric dilatation was not used. Maximum laser energy was required to break 19% of the stones, but no stone was encountered which could not be broken. Laser lithotripsy with this system is highly effective at all levels of the ureter; it is safe and it complements ultrasound-guided extracorporeal lithotripsy.

Female↗
PubMedDate not supplied

Laser lithotripsy of difficult biliary stones.

From June 1991 to September 1992, 16 patients (mean age, 72 +/- 5 years) were treated with intra-corporeal laser lithotripsy (ICL). Thirteen patients had choledocholithiasis with at least one stone larger than 20 mm; 3 patients had intra-hepatic lithiasis. All other methods, including mechanical lithotripsy, extra-corporeal lithotripsy (1 case), and intra-corporeal electrohydraulic lithotripsy (1 case), had failed to clear the bile ducts. Approaches for ICL were choledochoscopy with a "baby" endoscope via an existing sphincterotomy (8 cases), retrograde cholangioscopy with a gastroscope through a choledochoduodenal anastomosis or a sphincterotomy in patients with a gastrojejunal anastomosis (5 cases), and trans-hepatic cholangioscopy with a fibercholangioscope (3 cases, in 1 of which retrograde and trans-hepatic approaches were combined). Free bile ducts were obtained in 14/16 (87.5%) patients after a mean of 1.66 ICL sessions per patient. Mortality and laser-related morbidity did not occur; endoscopy-related morbidity was 12.5% for minor complications (1 transitory fever, 1 mild and transitory hemobilia) and 6.25% for major complications (1 post-sphincterotomy hemorrhage). Mean length of hospital stay was 11.5 +/- 2.5 days. We conclude that although it is rarely indicated and is expensive, ICL does offer a limited treatment option in selected patients. It allows the complete relief of complex biliary lithiasis. Morbidity is related to maneuvers preceding ICL, not to ICL itself.

Adult↗
PubMedDate not supplied

Laser lithotripsy of difficult bile duct stones by means of a rhodamine-6G laser and an integrated automatic stone-tissue detection system.

This report describes the initial clinical implementation of a new laser lithotripter system capable of effective fragmentation of common bile duct stones with a high degree of safety provided by an integrated stone-tissue detection system. This system automatically terminates laser pulse transmission if tissue contact is sensed. Eighteen patients with giant or impacted common bile duct stones refractory to standard treatment techniques were treated via the endoscopic retrograde route using a rhodamine-6G dye laser with an integrated stone-tissue detection system. In the event of tissue contact, the stone-tissue detection system cuts off the laser pulse after 190 ns (after transmission of 5% to 8% of the total pulse energy). Nine patients were treated under cholangioscopic control, and nine patients were treated blindly under fluoroscopic control using only standard duodenoscopes with either a 6F standard endoscopic retrograde cholangiopancreatography catheter (4 patients), a 6.8F balloon catheter (3 patients), or a laser lithotriptor basket (2 patients). Laser-induced fragmentation was achieved in all 18 patients (100%). Sixteen of 18 patients (89%) became completely stone-free after completion of the treatment, including additional intracorporeal shock wave lithotripsy in five patients. The only major complications occurred in one fully anticoagulated patient with a prosthetic heart valve who developed significant hemobilia and transient cholangitis but recovered after conservative treatment. Laser lithotripsy using the rhodamine-6G dye laser plus stone-tissue detection system appears safe and effective and allows "blind" fragmentation of difficult common bile duct stones to be performed under radiologic control.

Adult↗
PubMed1995

Technical tip: use of open-ended guidewire to facilitate laser lithotripsy during flexible ureteroscopy.

You have just passed your flexible ureteroscope to the level of the upper-ureteral calculus. The stone is in view, but as you advance the laser fiber, it fails to exit the ureteroscope. All measures to advance the fiber prove futile. Sound familiar? We have found this to be an all too common and frustrating situation with the use of the flexible ureteroscope during laser lithotripsy. Our review of the literature reveals that this subject has not been adequately addressed. We have been successful with the aid of an open-ended 0.035-inch guidewire that admits the 320-microns laser fiber.

Cost-Benefit Analysis↗
PubMed2004

Calculus fragmentation in laser lithotripsy.

The intracorporeal treatment of urinary calculi with lasers is presented, which describes laser-calculus interactions associated with lithotripsy. Reliable fragmentation of calculi with diverse compositions and minimal collateral tissue damage are primarily contingent upon laser parameters (wavelength, pulse duration, and pulse energy) and physical properties of calculi (optical, mechanical, and chemical). The pulse duration governs the dominant mechanism in calculi fragmentation, which is either photothermal or photoacoustical/photomechanical. Lasers with long pulse durations (i.e. > tens of micros) induce a temperature rise in the laser-affected zone with minimal acoustic waves; material is removed by means of vaporization, melting, mechanical stress, and/or chemical decomposition. Short-pulsed laser ablation (i.e. < 10 micros), on the other hand, produces shock waves, and the resultant mechanical energy fragments calculi. Work continues throughout the world to evaluate the feasibility of advanced lasers in lithotripsy and to optimize laser parameters and light delivery systems pertinent to efficient fragmentation of calculi.

Biophysical Phenomena↗
PubMed2001

Holmium: YAG laser lithotripsy for gallstones. A preliminary report.

BACKGROUND: Most retained gallstones can be extracted at the time of operative exploration or endoscopic retrograde cholangiopancreatography (ERCP). Infrequently, impaction or associated anatomic abnormalities may prevent their clearance. We assessed the efficacy of the holmium:YAG laser in managing retained biliary calculi that had proven refractory to the usual methods of extraction. METHODS: Two patients with calculi impacted in the intrapancreatic common bile duct and one patient with residual stones in a nonfunctional gallbladder were treated with holmium:YAG laser lithotripsy. Two of these patients were treated under conscious sedation, and one received a general endotracheal anesthetic. Laser energy was delivered by a 272-mm optical fiber inserted through a 7-Fr fiberoptic endoscope. The ablative effects were monitored continuously via videoscopic. RESULTS: All of the stones were cleared successfully in a single therapeutic setting. In one patient, fragments of the impacted intraductal stone were extracted with an endoscopic wire basket. In the other two patients, stone debris was completely cleared with saline irrigation. No complications developed, and all patients remained free of recurrence during a 6-month follow-up period. CONCLUSIONS: The holmium:YAG laser is a multidisciplinary instrument that is safe and effective in the fragmentation of both urinary and biliary calculi. Because it can be delivered through a small-caliber fiberoptic endoscope, it should be particularly useful to laparoscopic surgeons who manage complicated biliary tract disease.

Adult↗
PubMed1998

Holmium laser lithotripsy for ureteral calculi: an outpatient procedure.

A retrospective review was conducted to evaluate the efficacy of ureteroscopic lithotripsy using the holmium laser with a semirigid endoscope in a newly established day surgery center. In 1996, 69 consecutive patients (40 male and 29 female) with a mean age of 46.7 (range 21-73) years and ASA status I or II underwent ureteroscopic lithotripsy for their ureteral calculi using the holmium laser (365-micron fiber; power setting 0.5-1.4 J/5 Hz) and 8.5F semirigid ureteroscope in a day surgery setting. Stone features, postoperative pain scores, readmissions, and complications were evaluated. Eighteen upper, 17 middle, and 34 lower ureteral stones were treated, with a mean size measuring 12.1 (5-45) mm. The mean operative time was 61 minutes including the anesthetic time (range 15-150 minutes), and the success rate was 91% (63/69). The complication rate was 10% (7/69) including four unscheduled readmissions (6%). Telephone follow-up on postoperative Day 1 and Day 3 revealed mean pain scores of 2 and 1, respectively (on a 0-10 scale) and an analgesic requirement of 1 tablet of Dologesic (containing 32.5 mg of dextropropoxyphene + 320 mg of paracetamol) four times a day on both days. Ureteroscopic lithotripsy using the holmium laser and a semirigid endoscope is highly successful and well tolerated and carries a low complication rate. It is indicated as an ambulatory and minimally invasive treatment modality in low-risk patients with ureteral stones.

Adult↗
PubMed1998

Randomized study of intracorporeal laser lithotripsy versus extracorporeal shock-wave lithotripsy for difficult bile duct stones.

BACKGROUND: Endoscopic treatment modalities are well established for the removal of bile duct stones. For the small percentage of stones that are difficult or impossible to extract by conventional means, more sophisticated endoscopic techniques or associated modalities such as intracorporeal laser lithotripsy (ILL) and extracorporeal shock wave lithotripsy (ESWL) have to be applied. Little is known, however, about the relative value of these different techniques. We therefore compared endoscopic ILL with ESWL in patients with difficult bile duct stones in a prospective randomized study. METHODS: The study included 60 patients (35 women; mean age 70+/-15 years) with bile duct stones in whom standard extraction failed (n=33) or in whom the papilla was not accessible, thus requiring percutaneous access (n=27). They were randomized to receive ESWL under fluoroscopic targeting (maximum discharge number per session: 6000) or ILL using a pulsed dye laser with an automatic stone recognition system, which was mostly performed (28 of 30 cases) under cholangioscopic control. Endoscopic removal of fragments was attempted within the subsequent (ESWL) or the same (ILL) session. Failure was defined as failure to remove all ductal stones/fragments after a maximum of three lithotripsy sessions. RESULTS: There were no statistical differences in background variables between the two groups. Bile duct clearance was achieved in 22 of 30 patients (73%) in the ESWL group and in 29 of 30 patients (97%) in the ILL group (p < 0.05). The number of treatment sessions (ESWL 3.0+/-1.3; ILL 1.2+/-0.4; p < 0.001) and the duration of treatment (ESWL 3.9+/-3.5 days; ILL 0.9+/-2.3 days; p < 0.001) were also significantly different in favor of ILL. Two minor complications occurred in each group; there was no 30-day mortality. Crossover therapy to ILL led to stone removal in seven of the eight cases in which ESWL failed, whereas ESWL fragmented the stone in the single patient in whom ILL failed. CONCLUSIONS: ILL is more effective in the treatment of difficult bile duct stones than ESWL in terms of stone clearance rate and treatment duration.

Aged↗
PubMed1993

Efficacy of in vitro stone fragmentation by extracorporeal, electrohydraulic, and pulsed-dye laser lithotripsy.

Fragmentation has become the standard therapy for urinary calculi in the modern era. Stone fragility as well as position and size are important for the determination of a treatment program. To compare the efficacy of stone fragmentation, seven kinds of human urinary calculi with known composition (calcium oxalate monohydrate and dihydrate, dibasic calcium phosphate, uric acid, struvite, calcium phosphate, and cystine) were treated by three fragmentation techniques commonly used, namely extracorporeal shock wave (SWL), electrohydraulic (EHL), and pulsed-dye laser lithotripsy. Uric acid, calcium oxalate dihydrate, and calcium phosphate stones could be destroyed easily by any of these methods. Struvite was soft but sticky and not easy to break into tiny particles. Both dibasic calcium phosphate and calcium oxalate monohydrate stones were resistant to the laser and EHL; SWL is the treatment of choice. For cystine stones, none of the treatments was satisfactory; SWL was the only way to break them into large pieces.

Calcium Oxalate↗