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PubMed1990

Use of double-pigtail stents in extracorporeal shock wave lithotripsy.

Double-pigtail stents are placed commonly in patients before extracorporeal shock wave lithotripsy to prevent ureteral obstruction from steinstrasse. The use of double-pigtail stents in lithotripsy patients with a moderate stone burden was studied in a prospective randomized trial. Patients with unilateral renal stone(s) with at least 1 diameter between 7 and 25 mm. were eligible for the study. Fifty patients were randomized to a control or stented group. Double-pigtail stents with an attached suture were placed immediately before extracorporeal shock wave lithotripsy in the stented group. Stents were removed by the patients 1 week after lithotripsy. A survey on pain and associated symptoms was completed by patients at 1 and 14 days after treatment. There was no statistical difference in flank or abdominal pain, nausea, vomiting, temperature or use of analgesics at 1 and 14 days after extracorporeal shock wave lithotripsy in the control and stented groups. All patients in the stented groups complained of side effects attributable to the stent including urinary frequency and urgency, bladder pain, hematuria and flank pain with urination. Of 25 patients with stents 7 (27%) had early removal because of severe irritation, early migration or accidental removal. Among the patients with follow-up x-rays 1 month after treatment 17 of 21 (81%) in the control group and 12 of 19 (63%) in the stented group showed no evidence of remaining stones. The use of double-pigtail stents is not beneficial in patients with a moderate stone burden. Double-pigtail stents are associated with considerable patient discomfort but no decrease in symptomatic ureteral obstruction or final stone eradication rate.

Female↗
PubMed1988

Extracorporeal shock wave lithotripsy and its effect on renal function.

Extracorporeal shock wave lithotripsy has become a major treatment modality for symptomatic upper tract renal stone disease. Although proved to be effective in disintegrating stones the short-term and long-term effects on renal function are not yet known. We evaluated several basic physiological parameters, namely creatinine clearance, fractional sodium excretion, protein excretion and urine osmolality before and after extracorporeal shock wave lithotripsy in 26 consecutive patients in an attempt to quantitate changes in renal function. In addition, a 3 to 6-month followup study of patients showing excessive protein excretion with extracorporeal shock wave lithotripsy also is reported. Our data suggest that with extracorporeal shock wave lithotripsy transient nephrotic range proteinuria occurs immediately after treatment, returning to normal values within 3 to 6 months after treatment without a change in the glomerular filtration rate. The glomerular filtration rate increases after successful extracorporeal shock wave lithotripsy in patients with kidneys obstructed by the treated stone before the start of the procedure, and the kidney appears to maintain its ability to dilute urine and to conserve sodium after treatment.

Adult↗
PubMed1986

Extracorporeal shock wave lithotripsy in patients with a solitary kidney.

Extracorporeal shock wave lithotripsy was used to treat 68 patients with renal calculi in a solitary kidney. Epidemiological information, including stone number, size and location, was similar to that of other patients treated with extracorporeal shock wave lithotripsy. Renal function as measured by serum creatinine changed negligibly in the majority of the patients. Three patients had transient serum creatinine elevations greater than 2 mg. per dl. that were caused by obstruction from stone fragments. There were 2 perirenal hematomas that required transfusion. One patient required retrograde manipulation of a ureteral stone before extracorporeal shock wave lithotripsy, while 6 required stone manipulations after therapy for steinstrasses. Of 59 patients evaluable after extracorporeal shock wave lithotripsy 58 (98.3 per cent) had a successful result: 38 (64.4 per cent) were completely free of stones and 20 (33.9 per cent) had clinically insignificant residual fragments. Extracorporeal shock wave lithotripsy is effective and safe in a solitary renal unit. We believe that in most patients it is the procedure of choice. Attention to fever, urine output and fragment size perioperatively is crucial.

Adolescent↗
PubMed2001

A fishnet gantry for pediatric extracorporeal shock wave lithotripsy on the Sonolith 3000.

A new type of lithotripsy gantry composed of fishnet and bungee cords has been developed to allow proper patient positioning of infants and small children who undergo extracorporeal shock wave lithotripsy on the Sonolith 3000 lithotriptor. The materials are safe, inexpensive, easy to use, and do not interfere with shock wave delivery during a lithotripsy session. The gantry can be used for other lithotripsy machines that have a similar construction with a self-contained waterbath and a large lithotripsy table window.

Child↗
PubMed1987

Intracorporeal electrohydraulic shock wave lithotripsy of common bile duct stones: preliminary results in 7 cases.

We performed contact endobiliary electrohydraulic shock wave lithotripsy in 7 high-risk patient with unextractable common bile duct stones after EPT. The lithotripsy electrode was brought into contact with the stone through a percutaneous transhepatic approach in 5 cases and an endoscopic route in 5 cases. Firing of the shock wave was performed under fluoroscopic control in 4 patients and under endoscopic guidance via a transhepatic percutaneous cholangioscopy in 2 and peroral cholangioscopy in one case. Stones were fragmented in all the cases but one. Fragments were evacuated into the duodenum by simple lavage through the transhepatic drain in 5 cases, and by duodenoscopy in one. In 2 patients, hemobilia, which was controlled by transfusions, was observed. This type of percutaneous contact lithotripsy requires multiple maneuvers, which increase the risk and the hospital stay. Extracorporeal shock wave lithotripsy is simpler, but also has disadvantages. Peroral lithotripsy under endoscopic control performed immediately after EPT would be the most practical solution, but this technique implies the use of new fiberscopes and other energy supplies that are easier to handle.

Aged↗
PubMed2001

Extracorporeal shock wave lithotripsy for clearance of bile duct stones resistant to endoscopic extraction.

BACKGROUND: Endoscopic extraction of bile duct stones after sphincterotomy has a success rate of up to 95%. Failures occur in patients with extremely large stones, intrahepatic stones, and bile duct strictures. This study examined the efficacy and the safety of extracorporeal shock-wave lithotripsy in a large cohort of patients in whom routine endoscopic measures including mechanical lithotripsy had failed to extract bile duct stones. METHODS: Out of 1587 consecutive patients, endoscopic stone extraction including mechanical lithotripsy was unsuccessful in 313 (20%). These 313 patients (64% women, median age, 73 years) underwent high-energy extracorporeal shock-wave lithotripsy. Stone targeting was performed fluoroscopically (99%) or by ultrasonography (1%). RESULTS: Complete clearance of bile duct calculi was achieved in 281 (90%) patients. In 80% of the patients, the fragments were extracted endoscopically after shock-wave therapy; spontaneous passage was observed in 10%. For patients with complete clearance compared with those without there were no differences with regard to size or number of the stones, intrahepatic or extrahepatic stone location, presence or absence of bile duct strictures, or type of lithotripter. Cholangitis (n = 4) and acute cholecystitis (n = 1) were the rare adverse effects. CONCLUSIONS: In patients with bile duct calculi that are difficult to extract endoscopically, high-energy extracorporeal shock-wave lithotripsy is a safe and effective therapy regardless of stone size, stone location, or the presence of bile duct stricture.

Adult↗
PubMed2002

Clinical outcomes in patients who undergo extracorporeal shock wave lithotripsy for chronic calcific pancreatitis.

BACKGROUND: There is controversy as to whether extracorporeal shock wave lithotripsy fragmentation and ERCP retrieval of pancreatic stones are associated with relief of chronic pain or relapsing attacks of pancreatitis. Our most recent experience with this technology is reviewed. METHODS: Forty patients with chronic calcific pancreatitis who required extracorporeal shock wave lithotripsy between 1995 and 2000 to facilitate pancreatic duct stone removal were retrospectively reviewed. Data collected included patient presentation, number of lithotripsy and ERCP sessions required, complications, and outcomes measures to include pre- and post-ESWL pain scale, monthly oxycodone (5 mg)-equivalent pills ingested, yearly hospitalizations, and need for subsequent surgery. RESULTS: A single extracorporeal shock wave lithotripsy session was required for 35 patients who underwent a total of 86 ERCPs to achieve complete stone extraction from the main pancreatic duct. Minor complications occurred in 20%. There was one episode of pancreatic sepsis that was treated with antibiotics and removal of an occluded pancreatic prosthesis. At a mean [SD] follow-up of 2.4 (0.6) years, 80% of patients had avoided surgery and there was a statistically significant decrease in pain scores (6.9 [1.3] vs. 2.9 [1.1]; p = 0.001), yearly hospitalizations for pancreatitis (3.9 [1.9] vs. 0.9 [0.9]; p = 0.001), and oxycodone-equivalent narcotic medication ingested monthly (125 [83] vs. 81 [80]; p = 0.03). CONCLUSIONS: Extracorporeal shock wave lithotripsy fragmentation of pancreatic duct calculi in conjunction with endoscopic clearance of the main pancreatic duct is associated with significant improvement in clinical outcomes in most patients with chronic pancreatitis.

Adult↗
PubMed2001

Endoscopic lithotripsy with a new device combining ultrasound and lithoclast.

BACKGROUND AND PURPOSE: Endoscopic lithotripsy is still the method of choice for a number of stones, especially large stones. Various disintegration techniques exist. We investigated the combination of two of these techniques: ultrasound and pneumatic lithotripsy. PATIENTS AND METHODS: Fourteen consecutive patients with renal and one patient with bladder stones were treated with this new device. Ultrasound and pneumatic lithotripsy could be used independently or simultaneously. RESULTS: Disintegration and stone removal was fast. The use of forceps or other instruments could generally be avoided. No complications attributable to the lithotripsy device were observed. CONCLUSION: The combined ultrasound/pneumatic lithotripsy device is safe and highly effective. It reduces treatment time and enhances surgeon's comfort.

Adult↗
PubMed2003

Experimental study of the efficiency of lithotripsy with duplicate pulses.

BACKGROUND AND PURPOSE: Theoretical study had shown that compared with a single pulse, a duplicate pulse could improve the efficiency of lithotripsy. We conducted a series of studies to validate this idea. MATERIALS AND METHODS: The experimental study in vitro and in vivo used a lithotripsy machine with duplicate, single, and electromagnetic pulses. RESULTS: Use of a duplicate pulse improved the wastage of the model stones about 44.15% and the efficiency of lithotripsy about 44.76%. In pigs, the efficiency of lithotripsy was greater with a duplicate pulse than with single and electromagnetic pulses. CONCLUSION: Compared with single and electromagnetic pulses, duplicate pulses could improve the efficiency of lithotripsy by more than 40%.

Animals↗
PubMed2004

Ureteral ultrasonic lithotripsy revisited: a neglected tool?

BACKGROUND AND PURPOSE: Ultrasonic lithotripsy was one of the first modalities used for treating renal and ureteral stones. However, in recent years, it has been largely replaced by newer techniques such as laser lithotripsy with rigid as well as flexible ureteroscopes. The aim of this study was to review the results and our current indications for ureteroscopic ultrasonic lithotripsy (UUL). PATIENTS AND METHODS: Between October 2000 and May 2002, 340 ureteroscopies were performed for the treatment of ureteral stones in the Rabin Medical Center. Of this series, 9 patients (2.6%) underwent UUL using a semirigid 8F ureteroscope (Wolf) and an Olympus ultrasonic lithotripter (LUS-1) with a 4.5F hollow probe. Four patients had Steinstrasse following shockwave lithotripsy, four had large (1-2-mm) ureteral stones, and one had an impacted calcified ureteral double-J stent. Stones >5 mm were initially fragmented by the holmium laser (550-microm fiber). A double-J stent was placed in all patients. The mean follow-up time was 20 months. RESULTS: The mean operative time was 84 minutes. No intraoperative complications occurred. The mean hospital stay was 3.9 days. Eight patients became stone free after the first procedure, and the other underwent secondary ureteroscopy, which rendered him stone free. CONCLUSIONS: Patients in whom UUL is performed are relatively complex stone patients. The use of ultrasonic lithotripsy following, or in combination with, laser or ballistic devices utilizes the unique properties of UUL, which combines stone fragmentation and efficient removal of small fragments. The technique was particularly useful in patients with Steinstrasse or a large stone burden. Thus, UUL has a limited but significant role in the treatment of ureteral stones.

Adult↗
PubMed1995

Preliminary experience with holmium: YAG laser lithotripsy.

Lithotripsy with the pulsed-dye laser has been shown to be a safe and effective method of intracorporeal urinary stone fragmentation. Recently, a new device, the holmium: YAG laser, has been developed with both soft tissue and lithotripsy applications. We present our preliminary experience with the Ho:YAG laser for lithotripsy of urinary calculi. Ureteroscopy and lasertripsy resulted in successful fragmentation of ureteral stones in 92% of 21 patients when the laser was used alone or in combination with electrohydraulic lithotripsy. One complication directly related to the use of the laser occurred, a ureteral perforation, when the device was utilized under fluoroscopic control. In four patients undergoing percutaneous flexible nephrolithotripsy, the laser demonstrated utility in fragmenting caliceal stones remote from the nephrostomy tract. In summary, the Ho:YAG laser has demonstrated its efficacy as a method of intracorporeal lithotripsy. The tissue effects of this device, as well as the optimal energy/pulse and frequency settings, need further evaluation in order to minimize the risks of tissue injury.

Adult↗
PubMed1995

Ureteral lithotripsy with the electromechanical impactor.

Electrohydraulic lithotripsy (EHL) of ureteral calculi has proved to be an effective and relatively inexpensive method of intracorporeal lithotripsy. However, the potential for significant ureteral injury is an everpresent concern with conventional EHL. The electromechanical impactor (EMI), an innovative modification of a standard EHL probe, has been shown in initial investigations to be capable of fragmenting urinary calculi with a greater margin of safety. Herein, we describe our preliminary experience with this new device in 23 patients with ureteral calculi. In nine patients selected to undergo EMI treatment, the device could not be employed because of either inability to access the stone with the large endoscope required (six cases) or device malfunction (three cases). Among the patients in whom the EMI was used, five required an additional modality of intracorporeal lithotripsy to complete stone fragmentation. In the remaining nine patients, stone fragmentation was achieved with the EMI as the sole modality of lithotripsy, for an overall success rate of 39% (9/23). There were no complications directly related to use of the EMI as noted endoscopically or on postoperative imaging. The EMI appears to be a safe device for intracorporeal lithotripsy. Its application to a large population of patients with ureteral stones may be limited by the probe size (5F), which precludes its use with the smaller rigid and flexible ureteroscopes.

Adolescent↗
PubMed1998

Lipid peroxidation induced by shockwave lithotripsy.

To determine the relation between high-energy shockwaves (HESW) and the presence of lipid peroxidation produces, juvenile pigs were subjected to shockwave lithotripsy (SWL). After lithotripsy, both treated and control kidneys were analyzed, along with urine samples collected before, during, and after SWL. Thiobarbituric acid-reactive substance (TBARS) and lipid-conjugated diene (CD) concentrations, used as markers for membrane lipid peroxidation, were determined in the kidney and urine samples. Significantly increased mean TBARS concentrations (146%) were associated with homogenates of lithotripsy-treated kidneys, 77.8 +/- 14.4 (SD) mmol/g v the controls, 31.4 +/- 14.9 mmol/g. Lithotripsy induction of lipid peroxidation products in the cortex, the gross damage site, and the respective medulla were also examined. In HESW-treated cortex samples, increased TBARS concentrations were seen--75.0 +/- 21.3 mmol/g--compared with untreated controls-- 45.2+/- 5.6 mmol/g--while increased CD concentrations (168%) were observed in the medulla of HESW-treated samples. No significant differences were observed in TBARS or CD concentrations in urine samples from control or treated kidneys, yet specific lipid hydroperperoxides were detected in the urine of HESW-treated kidneys. We conclude that HESW lithotripsy of swine kidneys is associated with increased lipid peroxidation products that may cause further cellular damage. Lipid peroxidation induced by SWL may be one of several mechanisms that lead to other potential bioeffects. Finally, analysis of specific lipid hydroperoxides in the urine of HESW-treated kidneys may serve as a noninvasive marker of renal injury after clinical SWL.

Animals↗
PubMed1999

Identifying stone composition using infrared analysis of filtered urine after ureteroscopic lithotripsy.

BACKGROUND AND PURPOSE: With the development of small-caliber ureteroscopes and lithotripsy devices, it is now possible to perform intracorporeal stone fragmentation without dilatation of the ureteral orifice. Ureteral stones are typically fragmented into small particles that can be difficult to retrieve for stone analysis. Infrared spectroscopy (IRS) of the precipitate from urine after intracorporeal lithotripsy represents a method for obtaining stone analysis. PATIENTS AND METHODS: A total of 69 patients underwent ureteroscopic lithotripsy with the holmium laser or the electrohydraulic probe for stones in the ureter (N = 65) or kidney (N = 4). Each patient's bladder was then drained and the urine filtered. The resulting precipitate was analyzed using IRS. RESULTS: The amount of material for analysis was < or =1 mg in 56 patients (82%). Stone composition was positively identified in 44 patients (64%). Material suitable for analysis was recovered from 73% of patients when the bladder was drained with a cystoscope sheath compared with 43% when a urethral catheter was used (P = 0.03). There was no significant difference in pretreatment stone size in the patients who had a positive v a negative result (11.7 mm v 10.9 mm; P = 0.06). Similarly, the stone location was not significantly related to the likelihood of positive analysis (P = 0.29). CONCLUSION: Straining the urine after ureteroscopic intracorporeal lithotripsy and analyzing the precipitate with IRS is able to identify stone composition in the majority of patients. This method is especially useful in the setting of holmium laser lithotripsy, in which the majority of the stone is converted to spontaneously passable particles.

Female↗
PubMed2000

Laser lithotripsy and cyanide.

BACKGROUND AND PURPOSE: Holmium:YAG lithotripsy of uric acid calculi produces cyanide. The laser and stone parameters required to produce cyanide are poorly defined. In this study, we tested the hypotheses that cyanide production: (1) varies with holmium:YAG power settings; (2) varies among holmium:YAG, pulsed-dye, and alexandrite lasers; and (3) occurs during holmium:YAG lithotripsy of all purine calculi. MATERIALS AND METHODS: Holmium:YAG lithotripsy of uric acid calculi was done using various optical fiber diameters (272-940 microm) and pulse energies (0.5-1.5 J) for constant irradiation (0.25 kJ). Fragmentation and cyanide were quantified. Cyanide values were divided by fragmentation values, and fragment sizes were characterized. To test the second hypothesis, uric acid calculi were irradiated with Ho:YAG, pulsed-dye, and alexandrite lasers. Fragmentation and cyanide were measured, and cyanide per fragmentation was calculated. Fragment sizes were characterized. Finally, Ho:YAG lithotripsy (0.25 kJ) of purine and nonpurine calculi was done, and cyanide production was measured. RESULTS: Fragmentation increased as pulse energy increased for the 550- and 940-microm optical fibers (P < 0.05). Cyanide increased as pulse energy increased for all optical fibers (P < 0.002). Cyanide per fragmentation increased as pulse energy increased for the 272-microm optical fiber (P = 0.03). Fragment size increased as pulse energy increased for the 272-microm, 550-microm, and 940-microm optical fibers (P < 0.001). The mean cyanide production from 0.25 kJ of optical energy was Ho:YAG laser 106 microg, pulsed-dye 55 microm, and alexandrite 1 microg (P < 0.001). The mean cyanide normalized for fragmentation (microg/mg) was 1.18, 0.85, and 0.02, respectively (P < 0.001). The mean fragment size was 0.6, 1.1, and 1.9 mm, respectively (P < 0.001). After 0.25 kJ, the mean amount of cyanide produced was monosodium urate stones 85 microg, uric acid 78 microg, xanthine 17 microg, ammonium acid urate 16 microg, calcium phosphate 8 microg, cystine 7 microg, and struvite 4 microg (P < 0.001). CONCLUSIONS: Cyanide production varies with Ho:YAG pulse energy. To minimize cyanide and fragment size, Ho:YAG lasertripsy is best done at a pulse energy < or = 1.0 J. Cyanide production from laser lithotripsy of uric acid calculi varies among Ho:YAG, pulsed-dye, and alexandrite lasers and is related to pulse duration. Cyanide is produced by Ho:YAG lasertripsy of all purine calculi.

Cyanides↗
PubMed2002

Assessment of patient effective radiation dose and associated radiogenic risk from extracorporeal shock-wave lithotripsy.

The aim of the present study was to calculate patient effective dose and associated radiogenic risk from fluoroscopy guided extracorporeal shock-wave lithotripsy procedures. Fluoroscopy required during extracorporeal shock-wave lithotripsy was classified in two types identified by beam orientation: antero-posterior and 30 degrees anterior-oblique projected exposures. Duration of each exposure was monitored in 124 patients undergoing extracorporeal shock-wave lithotripsy treatment for ureteral stones. The dose from a kidney-ureter-bladder radiograph and the dose per min of fluoroscopy along antero-posterior and anterior-oblique projections were measured at 13 organs/tissues using an anthropomorphic phantom and thermoluminescence dosimetry. A radio-opaque object was placed in the phantom to simulate an ureteral stone at the proximal and distal ureter. The total effective dose in male and female patients with proximal ureteral stones was 1.71 mSv and 1.82 mSv, respectively. The corresponding values for male and female patients with distal ureteral stones was 0.76 mSv and 1.62 mSv, respectively. In the United States, the theoretical sex-averaged radiogenic excess of fatal cancers was estimated to be 140 per million and 85 per million of patients treated for proximal and distal ureteral stone, respectively. The average radiogenic risk for genetic defect associated to treatments of proximal and distal ureteral stones was found to be 2.5 and 24.4 per million of births, respectively. The radiation risk from a typical fluoroscopy guided extracorporeal shock-wave lithotripsy treatment of ureteral stones is low. Presented data may be used to determine patient effective dose from extracorporeal shock-wave lithotripsy procedures performed in any laboratory.

Dose-Response Relationship, Radiation↗
PubMed2004

Extracorporeal lithotripsy for salivary calculi: a long-term clinical experience.

OBJECTIVES/HYPOTHESIS: The objective was to assess in a large series of patients with a long-term clinical follow-up the validity of extracorporeal electromagnetic shock wave lithotripsy as a minimally invasive therapy for sialolithiasis. STUDY DESIGN: Consecutive patient series. METHODS: Three hundred twenty-two consecutive symptomatic outpatients with single or multiple calculi in the submandibular (234 patients) or parotid (88 patients) gland underwent a complete extracorporeal electromagnetic shock wave lithotripsy treatment. Treatment results were classified into three groups: successful result with complete ultrasonographic elimination of the stone after lithotripsy, successful result with residual ultrasonographic fragments that were less than 2 mm in diameter, and unsuccessful result with residual ultrasonographic fragments that were greater than 2 mm in diameter. Univariate and multivariate statistical analyses were performed. RESULTS: Complete elimination of the stone was achieved in 45% of patients. On ultrasonography, residual fragments (<2 mm in diameter) were detected in 27.3% of patients, and persisting fragments greater than 2 mm in diameter were assessed in 27.7% of patients. In 3.1% of patients, all with submandibular gland stones, sialoadenectomy was performed. Recurrence of calculi in the treated gland was observed during a median follow-up period of 57 months in four patients with complete ultrasonographic clearance of the stone occurring 10 to 58 months after lithotripsy. Univariate analysis showed that a favorable treatment result was significantly associated with the younger age of the patients (< or = 46 y), parotid and intraductal localization of the stone, diameter of the stone (< or = 7 mm), and number of therapeutic sessions (< or = 6). On multivariate analysis, the age of the patient, parotid site of the stone, stone diameter, number of therapeutic sessions, and number of shock waves were associated with favorable outcome. CONCLUSION: Extracorporeal electromagnetic shock wave lithotripsy is to be considered an efficient, minimally invasive treatment modality for salivary calculi.

Adolescent↗
PubMed2000

Update on contact lithotripsy.

Despite the development of extracorporeal shockwave lithotripsy, endoscopic stone removal, with or without intracorporeal lithotripsy, is still an effective minimally invasive alternative for special indications. There is no defined all-purpose lithotripsy procedure for contact lithotripsy. The choice of the lithotripsy procedure for endoscopic stone disintegration depends on a number of different factors, the main one being stone localization. Small calibre, flexible probes (electrohydraulic, pneumatic, laser) are especially appropriate for ureterorenoscopy, but the speed of stone disintegration is a limiting factor. In contrast, large calibre rigid probes (ultrasound) are clearly more effective, but are unsuitable in size for flexible ureterorenoscopy. This indicates that the type and size of the endoscope decisively influences the choice of devices for endoscopic stone disintegration. Additional inhibiting factors are the flexibility or the rigidity of the instrument and the diameter of the working channel. It must be noted that total costs are not only calculated on the purchase of the equipment, but must also cover disposable materials.

Humans↗