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PubMed1990

[Sonographic localization of ureteral calculi on extracorporeal shock wave lithotripsy].

Using the new Dornier lithotriptor MPL 9000* (multi-purpose lithotriptor) 381 treatments of urinary stones were performed from July 1988 to December 1989, 107 (28%) of them for ureteral calculi. Sonography enables stone localisation even in many cases where positioning by conventional x-ray fluoroscopy would not be possible. In 20 cases of upper ureteral stones, localization had to be performed partly by indirect measures, i.e. at the end of the dilated ureter. In 10 ureteral stones of the middle third sonographic positioning and complete disintegration was achieved. Treatment was without anaesthesia and was performed in a comfortable supine position. Therapy of 77 ureteral calculi in the caudal part--without anaesthesia--has proved extremely successful. Since it is less invasive than other measures (e.g. uretero-renoscopy or loop extraction), it is now the method of choice for the treatment of stones in the middle and lower third of the ureter.

Adolescent↗
PubMed1987

[Results of sonographic diagnosis of ureteral calculi].

In a retrospective study in 61 cases of sonographically, roentgenologically and clinically diagnosed calculi in the ureter, the sensitivity was found to be 64%. During the observation period of 2 years this increased from 69% to 84% with experienced investigators. Investigators with less than one year's experience achieved a level of 14%. Diagnosis of calculi in the ureter requires a special examination method using sector scanners. The results are additionally influenced by ureteral width, filling of the urinary bladder, meteorism and adiposity. If sonographic diagnosis is skillfully handled, it becomes possible to restrict the use of the I.V. pyelogram to a few instances and indications only.

Diagnosis, Differential↗
PubMed1985

Childhood urolithiasis in Iran: a comparative study on the calculi composition of 121 cases.

Within 12 years, 165 cases of urolithiasis were observed at the Children's University Hospital of Teheran. The incidence of urolithiasis amounts to 1 case in 300 paediatric hospitalizations. 160 calculi from 121 children were analysed by various methods: semiquantitative chemical analysis (Mercognost), x-ray diffraction, polarising microscopy on thin sections. In about 25% of the cases metabolic disorders or malformations were found responsible for urolithiasis. In 100 cases, stone formation was attributed to the upper and in 21 cases to the lower urinary tract. Calcium oxalates are the most frequent constituents, followed by ammonium acid urate. The core of the stones in the upper tract was mostly composed of calcium oxalate. Ammonium acid urate was the second important core component, but occurred especially enriched in the lower urinary tract. On the basis of these and literature data, the lack of ammonium acid urate in juvenile stones in Europe and the USA seems surprising. Thus, it must be assumed therefore, that ammonium acid urate is a key to understanding the formation of endemic calculi. The cases studied support that with increasing standard of living, the incidence of bladder stones decreases.

Adolescent↗
PubMed2003

Multiple vesical calculi and complete vaginal vault prolapse.

Multiple-vessel calculi in the setting of pelvic organ prolapse is rare. Long-standing prolapse and bladder outlet obstruction, coupled with chronic infection are suspected to be the inciting factors in this case. To remove the calculi, an open cystolithotomy was performed at the time of an abdominal anti-incontinence procedure.

Aged↗
PubMed2006

Extracorporeal shock-wave lithotripsy monotherapy of partial staghorn calculi. Prognostic factors and long-term results.

OBJECTIVE: To define factors affecting the success and long-term outcome of extracorporeal shock-wave lithotripsy (ESWL) monotherapy of partial staghorn calculi. MATERIAL AND METHODS: We retrospectively reviewed 92 patients with partial staghorn calculi who were treated with ESWL monotherapy. The outcome of the treatment was evaluated after 3 months. Long-term follow-up data (>24 months) were available for 49 patients. These data were further analyzed to determine long-term outcome. RESULTS: At 3 months, the overall stone-free rate was 59.8%. Multiple ESWL sessions were required in 85.8% of patients. Stone surface area>500 mm2 was the only factor that significantly decreased the stone-free rate. Post-ESWL complications occurred in 12 patients (13%), among whom renal obstruction was observed in 10.8%. Secondary procedures were needed in 17 cases (18.4%). After a mean follow-up period of 7.5 years, the stone-free rate was 59.2% (29/49) and one-third of patients developed recurrence. In the long term, clinically insignificant residual fragments (CIRFs) passed spontaneously in 23% of patients, remained stable in 38.5% and became bigger in 38.5%. Regrowth of CIRFs was related to a history of stone recurrence. No patients showed deterioration of kidney function on the treated side and an improvement in pre-ESWL hydronephrosis was observed in 73.3% of patients. CONCLUSIONS: ESWL is suitable for staghorn stones<or=500 mm2. In the long term, CIRFs became bigger and required secondary intervention in one-third of patients. A history of stone recurrence is a significant predictor of regrowth of CIRFs. ESWL provides long-term preservation of function of the treated kidneys; however, one-third of patients develop recurrence.

Adult↗
PubMed1999

Extracorporeal shock wave lithotripsy as monotherapy for staghorn calculi--is reduced renal function a relative contraindication?

Extracorporeal shock wave lithotripsy as monotherapy for staghorn calculus is not without complications. We describe a case in which, due to markedly reduced renal function following lithotripsy for a staghorn calculus, broken fragments of calculi forming steinstrasse became cemented together to form a solid calcified tube extending from the renal pelvis to the ureteric orifice. This resulted in further loss of kidney function. The patient eventually required nephro-ureterectomy. Extreme care should be taken when using extracorporeal shock wave lithotripsy to treat staghorn calculi in kidneys with markedly diminished function to prevent further loss of function due to treatment.

Adult↗
PubMed2000

Ureteroscopy for proximal ureteral calculi: prevention of stone migration.

BACKGROUND: The cephalad migration of proximal ureteral calculi accounts for a high percentage of ureteroscopic failures. PATIENTS AND METHODS: A balloon on a wire is a single-channel 0.038-inch hollow guidewire with a low-profile balloon, which is inflatable to 12F. Forty-two consecutive patients with proximal ureteral calculi underwent ureteroscopy with the aid of this device. RESULTS: Twenty-nine patients had successful placement of the balloon on a wire above the stone. Of those 29 patients, 26 became stone free with a single procedure. CONCLUSION: The balloon on a wire is a useful tool to aid in the prevention of proximal ureteral stone migration during ureteroscopy and to minimize the number of secondary procedures. In addition, it appears to be cost-effective.

Catheterization↗
PubMed2002

Single upper-pole percutaneous access for treatment of > or = 5-cm complex branched staghorn calculi: is shockwave lithotripsy necessary?

BACKGROUND AND PURPOSE: Percutaneous nephrolithotomy for staghorn calculi is reported to have a residual stone rate of 28%, while shockwave lithotripsy alone results in residual stones in approximately 50% of cases. Combination therapy, sandwich therapy, and multiple percutaneous accesses have also been advocated for staghorn stones. We believe these stones can often be removed with a staged procedure via a single upper-pole percutaneous access using flexible nephroscopy and the holmium:YAG laser. Our experience is reviewed. PATIENTS AND METHODS: The hospital records of patients having a cumulative stone burden > or =5 cm who underwent percutaneous nephrolithotripsy (PCNL) for a single complex staghorn calculus were reviewed. There were 15 male and 34 female patients having 45 complete and 7 partial staghorn calculi constituting a mean stone burden of 6.7 cm (range 5.0-10.0 cm). A calix was punctured that would provide access to the majority of the involved calices. Thirty-five renal units were approached through a single upper-pole percutaneous access, and four and six renal units were accessed through single middle or lower-pole calices, respectively. The remaining seven renal units were treated with multiple percutaneous accesses. RESULTS: In the renal units having only a single access, a mean of 1.6 (range 1-3) procedures were required to achieve stone-free status. The mean operating room time was 2.9 hours (range 2.0-3.5 hours). For the second PCNL, the mean operating room time was 63 minutes (range 30-90 minutes). Two patients (two renal units) had residual stones <1 cm in diameter. One refused additional surgery, and the other is awaiting further treatment. The mean estimated blood loss was 238 mL (range 50-800 mL), with only one procedure (2.2%) necessitating a blood transfusion. One (2.8%) hydrothorax developed among the 35 upper-pole puncture cases. Six patients had transient oral temperature readings >101 degrees F with negative blood cultures. Other early complications included single cases of leg cellulitis, atrial fibrillation, and noncardiac chest pain. There were no delayed surgical complications. Patients were discharged from the hospital a mean 2 days (range 1-10 days) after the first PCNL. CONCLUSION: Use of flexible nephroscopy with holmium:YAG laser lithotripsy and Nitinol basket stone extraction has allowed us to render staghorn-containing renal units stone free in a mean of 1.6 procedures. Of the 45 renal units treated through a single percutaneous access, 43 (95%) were rendered stone free. The holmium:YAG laser appears to be a safe lithotrite for the kidney, as no complications occurred from its use.

Adult↗
PubMed2004

Bilateral renal calculi: assessment of staged v synchronous percutaneous nephrolithotomy.

BACKGROUND AND PURPOSE: Percutaneous stone removal has replaced open renal surgery and has become the treatment of choice for large or complex renal calculi. However, patients with large bilateral stone burdens still present a challenge. Simultaneous bilateral percutaneous nephrolithotomy (PCNL) has been demonstrated to be a well-tolerated, safe, cost-effective, and expeditious treatment. We present what is, to our knowledge, the first large retrospective series comparing synchronous and asynchronous bilateral PCNL. PATIENTS AND METHODS: A chart review was performed on 26 patients undergoing 57 PCNLs for bilateral renal calculi over a 7-year period. Seven patients received synchronous PCNL (same anesthesia; Group 1), and 19 patients underwent asynchronous PNL (procedures separated by 1-3 months; Group 2). Complete surgical and hospital records were available on all patients. The average stone burden for Group 1 was 8.03 cm(2) on the left and 9.18 cm(2) on the right v 10.1 cm(2) on the left and 14.23 cm(2) on the right for Group 2 (P> 0.05). Variables of interest included anesthesia time, operative time, blood loss, transfusion rates, length of hospital stay, and complication rates. Each variable was evaluated per operation and per renal unit. Follow-up imaging with stone assessment was available on 20 patients. RESULTS: Group 1 required 1.14 access tracts per renal unit to attempt complete clearance of the targeted stones v 1.88 tracts per renal unit in Group 2 (P> 0.05). The average operative time per renal unit was significantly less in Group 1 (83 minutes) than in Group 2 (168.5 minutes) (P< 0.0001), as was blood loss (178.5 mL v 307.4 mL, respectively; P= 0.02). However, blood loss per operation was similar at 357 mL in Group 1 and 282 mL in Group 2. Comparable transfusion rates of 28.6% and 36.8%, respectively, were noted. Forty percent of the patients in Group 1 were completely stone free compared with 36% of the patients in Group 2; however, an additional 50% and 57%, respectively, had residual stone burden <4 mm (P> 0.05). Complications occurred in 2 of 7 operations (28%) in Group 1 and 8 of 42 operations (19%) in Group 2. The total length of hospital stay was nearly doubled for patients undergoing staged PCNL (P= 0.0005). CONCLUSIONS: These results demonstrate similar stone-free rates, blood loss per operation, and transfusion rates for simultaneous and staged bilateral PCNL. The reduced total operative time, hospital stay, and total blood loss, along with the requirement for only one anesthesia, makes synchronous bilateral PCNL an attractive option for select individuals. However, in patients with larger, less easily accessible stones, excessive bleeding may be encountered more frequently on the first side, thereby delaying management of the second side to a later date. Synchronous bilateral PCNL should be considered in patients in whom the first stage of stone removal is accomplished quickly and safely.

Adolescent↗
PubMed1993

Lasertripsy of ureteral calculi using pulsed-dye laser with automatic shut-off after tissue contact.

Since June 1991, 54 patients with ureteral calculi (13 upper, 18 middle, and 23 distal) have been treated in our department using a flashlamp-pumped tunable-dye (rhodamine 6G) laser with a wavelength of 594 nm with an energy at the distal fiber tip between 30 and 120 mJ. The fiber core diameters were 200 and 300 microns. By spectral analysis of the reflected light, immediate shut-off of the laser was obtained after tissue contact. In average, 1599 impulses at a mean energy of 76.4 mJ were applied. In 32 cases (59%), complete disintegration was achieved. In 22 cases (41%), partial disintegration was noted, leading to retrograde mobilization of the fragments followed by SWL in 16 patients. Ureteroscopic extraction of fragments was performed in six patients. All patients were rendered stone free after 6 weeks. Because of the ureteroscopic manipulation, mucosal lesions were found in five patients, but no trauma attributable to the action of the laser was seen. In 42 patients, a double-J stent was placed after the procedure. Lasertripsy using a pulsed-dye laser with automatic shut-off after tissue contact is a safe and effective approach that offers a new aspect in the noninvasive treatment of recalcitrant ureteral calculi in our department.

Automation↗
PubMed1993

Extracorporeal shock wave lithotripsy monotherapy of staghorn calculi with Dornier MFL 5000.

A retrospective study was conducted of the efficacy of extracorporeal shock wave lithotripsy (SWL) monotherapy for the management of 31 patients with staghorn calculi (mean size 5.2 cm2). Five patients were lost to follow-up, 10 were stone-free in the end, and 11 had effective disintegration with small residual fragments. The remaining five patients required open surgery because of insufficient stone fragmentation. According to our data, SWL monotherapy is not sufficient for achieving stone-free status in patients with staghorn calculi, but it relieves obstruction and decreases the stone bulk in the majority of them.

Adult↗
PubMed1993

Long-term results of endourologic treatment of urinary calculi: investigation of risk factors for recurrence or regrowth.

To evaluate the risk factors related to the long-term outcome of endourologic treatment of urinary calculi, we examined rates of recurrence and regrowth in 167 renal units. The following risk factors were examined: age; previous stone; location, number, size, and composition of stone; and procedures. In our study sample, the overall recurrence and regrowth rates were 17% and 10%, respectively. The earliest recurrence and regrowth appeared at 3 months after treatment, and 71% occurred within 2 years. In 22% of renal units that were estimated to be stone-free, stones appeared later, and 45% of inadequately fragmented stones enlarged. Stones located in a renal calix and pelvis, multiple stones, large stones (more than 20 mm), stones composed of calcium oxalate or calcium phosphate or both, and struvite stones were likely to be risk factors, but there were no significant differences statistically. Although the possibility of several risk factors was suggested in our study, thorough fragmentation of stones and complete removal of fragments, combined with extracorporeal shock wave lithotripsy or chemolysis if needed, is ultimately responsible for successful treatment of urinary calculi.

Adolescent↗
PubMed1993

Acoustic and mechanical properties of renal calculi: implications in shock wave lithotripsy.

The acoustic and mechanical properties of renal calculi dictate how a stone interacts with the mechanical forces produced by shock wave lithotripsy; thus, these properties are directly related to the success of the treatment. Using an ultrasound pulse transmission technique, we measured both longitudinal and transverse (or shear) wave propagation speeds in nine groups of renal calculi with different chemical compositions. We also measured stone density using a pycnometer based on Archimedes' principle. From these measurements, we calculated wave impedance and dynamic mechanical properties of the renal stones. Calcium oxalate monohydrate and cystine stones had higher longitudinal and transverse wave speeds, wave impedances, and dynamic moduli (bulk modulus, Young's modulus, and shear modulus), suggesting that these stones are more difficult to fragment. Phosphate stones (carbonate apatite and magnesium ammonium phosphate hydrogen) were found to have lower values of these properties, suggesting they are more amenable to shock wave fragmentation. These data provide a physical explanation for the significant differences in stone fragility observed clinically.

Humans↗
PubMed1994

Primary extracorporeal shockwave lithotripsy in management of large bladder calculi.

Large bladder calculi are often outside the range of treatment with conventional endoscopic lithotrites because of either anatomic factors or the mechanical limits of available instruments. Alternative methods of cystolithotripsy: ultrasonic, electrohydraulic, or laser, can prove time-consuming or even hazardous, so that open surgery is often the most expeditious option. We report our experience using Dornier HM3 extracorporeal shockwave lithotripsy (SWL) for initial bladder stone reduction preparatory to transurethral litholapaxy and definitive treatment of any underlying obstructive pathology. Primary cystolitholapaxy was judged impractical in these 24 patients (21 adults and 3 children) presenting 31 large bladder stones (mean size 35.6 mm). In all patients, primary transpelvic SWL was followed immediately by endoscopic evacuation of stone debris or cystolitholapaxy. In addition, 10 of the 24 patients (42%) underwent a definitive endoscopic operation for treatment of an underlying obstructive lesion at either the same or a follow-on session. Morbidity was minimal, and the mean hospital stay after the initial SWL treatment was 3.5 days. In our experience, Dornier SWL has proved invaluable in enabling cystolitholapaxy of very large bladder calculi that would otherwise require protracted and difficult endoscopic manipulation or open surgery.

Adolescent↗
PubMed1995

Cost-effectiveness v patient preference in the choice of treatment for distal ureteral calculi: a literature-based decision analysis.

Ureteroscopy (URS) and extracorporeal shockwave lithotripsy (SWL) battle for supremacy in the management distal ureteral calculi. In order to clarify issues surrounding this controversy, we created a decision tree modeling URS or SWL with literature-based probabilities and used as endpoints both cost and patient preferences. Ureteroscopy was more successful than single-session or multiple-session SWL, 92.1% v 74.3% or 84.5%, and had a lower retreatment/complication rate. Although initial SWL was only slightly more expensive than URS, $4,420 v $4,337, the difference increased when the additional costs of complications and retreatment were calculated, $6,745 v $5,555. Using values for an "average" patient, SWL was preferred to URS in terms of patient satisfaction. The most important factors distinguishing between URS and SWL were the success of treatment, the cost of initial therapy, and patient attitudes toward unplanned ancillary procedures and retreatment. Although no alteration of success rates and cost figures within reasonable ranges made URS less cost-effective than SWL, individual differences in patients' aversion for complications allowed URS to be preferred to SWL in some situations. Therefore, SWL is less cost-effective than URS and is not necessarily preferred by patients. The physician should be aware of the principal determinants of the choice between URS and SWL treatment of distal ureteral calculi.

Cost-Benefit Analysis↗
PubMed1996

Endoscopic ballistic lithotripsy in the treatment of bladder calculi in patients with neurogenic voiding dysfunction.

Bladder stones represent a troublesome complication in patients suffering from neurogenic voiding dysfunction, in whom prompt and effective therapy is required. A variety of endoscopic lithotripsy methods are available; however, current devices can be tedious to use. We have treated 17 patients affected by bladder calculi and spinal cord injury or multiple sclerosis by means of the ballistic lithotripter EMS Swiss Lithoclast. The mean diameter of the stones was 2.7 cm. The mean operative time was 27 minutes. There were five intraoperative complications, including crises of autonomic dysreflexia (three patients) and light hematuria (two patients). There was no malfunction of the lithotripter and no long-term complications. All the patients were stone free at 6 months postoperatively. In conclusion, endoscopic lithotripsy with the ballistic lithotripter proved to be a very effective, rapid, and safe method for treating bladder calculi in patients with neurogenic bladders.

Adult↗
PubMed1996

Management of vesical calculi: comparison of lithotripsy devices.

Although endoscopic lithotripsy of bladder stones has been well described and is widely practiced, comparison of the main modalities of mechanical, electrohydraulic, and ultrasonic lithotripsy is lacking. The exact role of these and other modalities such as the Swiss Lithoclast and extracorporeal shockwave lithotripsy is not clearly defined. The safety and efficacy of the various lithotripsy modalities available to treat bladder calculi were reviewed retrospectively over an 18-year period. A total of 106 patients were treated with some form of intracorporeal lithotripsy. In general, all devices proved to be effective with a low rate of complications. The addition of transurethral resection of the prostate to bladder stone management under the same anesthetic was also found to be a safe procedure for moderate benign prostatic hyperplasia. In summary, transurethral endoscopic lithotripsy is a safe and effective method of bladder stone management both alone and in combination with transurethral prostatectomy. All modalities of intracorporeal lithotripsy are effective; however, devices such as ultrasound lithotripters or the Swiss Lithoclast that utilize larger, rigid probes may be more efficient for patients with large or particularly hard vesical calculi.

Adolescent↗
PubMed1997

High-energy v low-energy shockwave lithotripsy in treatment of ureteral calculi.

The size of the crater formed in a urinary calculus subjected to shockwave lithotripsy (SWL) is directly proportional to the energy delivered to the stone surface. This study compared the effect of high and low energy levels on the outcomes of ureteral SWL. Ureteral calculi (N = 336) were treated with the conventional low-energy Siemens Lithostar and 62 with the higher-energy (1.02 v 0.5 mJ/mm2) modification of the Lithostar, the Siemens Shock Tube C. Stone locations included all regions of the ureter. The average stone treated with the standard Lithostar measured 8.1 mm in diameter and received 5461 shockwaves (treatment time 45 minutes) at 17.2 kV (range 14.5-19.0 kV). The stone-free rate was 72%, with stents being used in 16% of patients and a retreatment rate of 9%. The typical stone treated with Shock Tube C was 10.4 mm in diameter and received 3528 shockwaves (treatment time 30 minutes) at an average energy setting of 4.1 (range 1.5-8.0). The stone-free rate was 75%, with stents being used in 9.8% of cases, and a retreatment rate of only 1.6% (P < 0.003). In this study, Shock Tube C yielded stone-free rates equivalent to those of the conventional machine. However, the number of shockwaves, treatment time, and retreatment rate were significantly lower with the new shock tube. High-energy lithotripsy is more efficient than low-energy treatment of ureteral calculi.

Humans↗