Steinstrasse after extracorporeal shockwave lithotripsy: aetiology, prevention and management

Extracorporeal shock wave lithotripsy versus laser lithotripsy in the treatment of post-SWL steinstrasse: a randomized comparative study

OBJECTIVE

To compare the efficacy of Holmium laser lithotripsy with that of extracorporeal shock lithotripsy (SWL) for post-SWL ureteral steinstrasse.

MATERIALS AND METHODS

From January 2022 to July 2023, 36 patients with post-SWL ureteral steinstrasse were randomly divided into laser lithotripsy and SWL groups. Patients with pain, moderate to marked hydronephrosis, large leading stone fragments, and showing no spontaneous resolution within 3-4 weeks after medical expulsive therapy were included. Patients with sepsis were excluded. The success rate was the primary outcome. We compared the perioperative data between the groups.

RESULTS

The success rate was higher in the ureteroscopy group than in the SWL group (p = 0.034). SWL was a significantly longer operation, and the fluoroscopy time was significantly longer in the SWL group than in the URS group (p = 0.027). Auxiliary procedures were more frequently performed in the SWL group than in the URS group (p = 0.02). JJ stents were inserted in 100% of patients in the URS group. Three patients (16.7%) underwent conversion to laser ureteroscopy after the second SWL session failed. No significant difference in the incidence of postoperative complications was observed between the groups, but the incidence of postoperative LUT was high in the ureteroscopy group. The mean hospital stay was 30 h in the ureteroscopy group. SWL was performed without the need for hospital admission.

CONCLUSION

Ureteroscopic laser lithotripsy for steinstrasse was safe and effective, with a higher success rate, shorter fluoroscopy time, and shorter recovery period than SWL.

Prospective Evaluation of Extracorporeal Shockwave Lithotripsy in Renal and Upper Ureteric Stone Treatment: Clinical Assessment and Results

INTRODUCTION

Extracorporeal shockwave lithotripsy (ESWL) is a widely accepted non-invasive treatment for renal and upper ureteric stones smaller than 2 cm due to its safety and efficacy. Despite advancements in minimally invasive techniques, extracorporeal shockwave lithotripsy remains an important modality.

AIMS AND OBJECTIVE

This prospective observational study aimed to evaluate the outcomes of ESWL in managing renal and upper ureteric stones measuring less than 2 cm in terms of stone clearance.

MATERIAL AND METHODS

In a study conducted at a university-affiliated tertiary care hospital, 119 patients with renal and upper ureteric stones underwent extracorporeal shockwave lithotripsy over a 12-month period. Data on patient demographics, stone characteristics, treatment procedures, and complications were collected. Follow-up assessments were performed at two-week intervals for up to two months post-treatment.

RESULTS

The mean age of patients was 39.78 years, with a mean stone size of 1.2 cm. Right kidney stones were more prevalent (61.3% [n=76]). Complications included fever (19.3% [n=23]), gross haematuria (24.3% [n=29]), and steinstrasse (21.8% [n=26]). The success rate of extracorporeal shockwave lithotripsy was 81.5% (n=97), with 18.5% (n=22) of patients requiring surgical intervention due to incomplete fragmentation or residual fragments >4 mm. Stone size and density played significant roles in treatment success.

CONCLUSION

Despite advancements in minimally invasive techniques, ESWL retains its significance as a noninvasive and effective treatment option for renal and upper ureteric stones smaller than 2 cm. Its success depends on various factors, including the stone site, size, and composition. ESWL offers advantages such as minimal morbidity, shorter hospital stays, and better patient compliance. Complications such as steinstrasse are manageable with conservative measures or ancillary procedures. While ESWL may be losing ground in some cases, its noninvasive nature and favourable outcomes make it a valuable option in the armamentarium for stone management.

Safety and Efficacy of Retrograde Intrarenal Surgery in the Solitary Kidney: A Propensity Score-Matched Analysis of the RIRSearch Study Groups' Results

Background: The aim of this study was to evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) in patients with renal calculi with solitary kidneys (SKs). Materials and Methods: In this retrospective, multicenter study, a matched case-control study was carried out using the data from 522 RIRS patients treated between 2014 and 2021. Patients' demographic data, stone characteristics, operative outcomes, perioperative and postoperative complications, and surgical success were analyzed. All patients were evaluated with noncontrast-enhanced computed tomography (NCCT) preoperatively and 1 month after the surgery. Surgical success was defined as no evidence of remaining residual fragments of <3 mm in the first-month postoperative NCCT images. The case group of 29 patients with SKs (Group 1) treated with RIRS were matched with 76 control patients (Group 2) with bilateral kidneys, who underwent unilateral RIRS by propensity score-matched (PSM) analysis. Results: After PSM analysis, the demographic and clinical data did not differ significantly between the groups. The stone burden was similar between the groups: 733.6 mm3 (range: 50.4-7565.9) versus 991.1 mm3 (range: 201.2-4380.6) (P = .09), respectively. The perioperative complication rates were 13.8% (n = 4) in Group 1 and 11.8% (n = 9) in Group 2 (P = .78). There was no statistically significant difference between the groups for postoperative complication rates (minor complications, classified as Clavien 1 or 2), (6.9% [n = 2] versus 13.2% [n = 10; P = .34]), respectively. Surgical success was 82.8% (n = 24) in Group 1 and 83.6% in Group 2 (P = .92). There was no significant difference between preoperative and postoperative glomerular filtration rate and creatinine values (P = .005). Conclusions: Our results support that RIRS is a safe and effective treatment method in SK patients with similar complication and stone-free rates compared to patients who had bilateral functional kidneys and underwent unilateral RIRS.

2022 Recommendations of the AFU Lithiasis Committee: Extracorporeal shock wave lithotripsy (ESWL)

Extracorporeal shock wave lithotripsy (ESWL) is a minimally invasive technique for the fragmentation of urinary tract stones using shock waves under fluoroscopic and/or ultrasound guidance. ESWL results depend on the indication (stone size/composition, clinical context) and also on how it is performed. The stone structure, nature and density (Hounsfield units; evaluated by CT without contrast agent) influence the fragmentation achieved by ESWL. The upper size limit of kidney stones has been lowered to 15mm (1.68cm3) due to the increased risk of steinstrasse with larger sizes and the potential need of anesthesia and ureteral stenting. Conversely, the development of endourological technologies allows a finer stone fragmentation and/or better elimination, thus reducing the risk of steinstrasse and decreasing the potential number of sessions or additional interventions. METHODOLOGY: These recommendations were developed using two methods: the Clinical Practice Recommendations method (CPR) and the ADAPTE method, depending on whether the question was considered in the European Association of Urology (EAU) recommendations (https://uroweb.org/guidelines/urolithiasis [EAU 2022]) and their adaptability to the French context.

Using vacuum-assisted ureteral access sheath in the treatment of complex steinstrasse

Steinstrasse is an iatrogenic condition resulting from upper urinary tract lithotripsy. Uncomplicated steinstrasse can be managed expectantly. Complex steinstrasse can pose a therapeutic challenge. The vacuum-assisted ureteral access sheath (vaUAS) is similar to a conventional ureteral access sheath but has a side branch that can be connected to vacuum apparatus. This device seemed to be useful in the management of complex steinstrasse. 35 patients with complex steinstrasse, defined as steinstrasse containing ≥ 4 stones or with an aggregate length of ≥ 1.5 cm, were treated in four tertiary medical centers using the vaUAS in this prospective and non-randomized study. The vaUAS was inserted into the ureter over a guidewire until the tip of the vaUAS was in contact with the lowermost stone fragment. A 7 Fr./8.4 Fr. semirigid ureteroscope and a holmium laser were used to pulverize the obstructing stone. All the stone fragments were aspirated either in the space between the scope and the sheath, or through the channel of the sheath by withdrawing the scope to the proximal of the aspiration port. All patients were steinstrasse-free at end of the procedure, as assessed visually and by KUB. At the 3-month follow-up, 94.3% of patients were stone-free with or without a supplementary procedure. There were no perioperative complications. Five patients experienced postoperative fever and/or significant hematuria, and one patient had transient sepsis, a grade I and IV Clavien complication, respectively. vaUAS can be an effective adjunctive device in the management of complex steinstrasse.

International Alliance of Urolithiasis Guideline on Shockwave Lithotripsy

Different international associations have proposed their own guidelines on urolithiasis. However, the focus is primarily on an overview of the principles of urolithiasis management rather than step-by-step technical details for the procedure. The International Alliance of Urolithiasis (IAU) is releasing a series of guidelines on the management of urolithiasis. The current guideline on shockwave lithotripsy (SWL) is the third in the IAU guidelines series and provides a clinical framework for urologists and technicians performing SWL. A total of 49 recommendations are summarized and graded, covering the following aspects: indications and contraindications; preoperative patient evaluation; preoperative medication; prestenting; intraoperative analgesia or anesthesia; intraoperative position; stone localization and monitoring; machine and energy settings; intraoperative lithotripsy strategies; auxiliary therapy following SWL; evaluation of stone clearance; complications; and quality of life. The recommendations, tips, and tricks regarding SWL procedures summarized here provide important and necessary guidance for urologists along with technicians performing SWL. PATIENT SUMMARY: For kidney and urinary stones of less than 20 mm in size, shockwave lithotripsy (SWL) is an approach in which the stone is treated with shockwaves applied to the skin, without the need for surgery. Our recommendations on technical aspects of the procedure provide guidance for urologists and technicians performing SWL.

Development and validation of a predictive model for major complications after extracorporeal shockwave lithotripsy in patients with ureteral stones: based on a large prospective cohort

The risk factors of complications after SWL are not well characterized. Therefore, based on a large prospective cohort, we aimed to develop and validate a nomogram for predicting major complications after extracorporeal shockwave lithotripsy (SWL) in patients with ureteral stones. The development cohort included 1522 patients with ureteral stones who underwent SWL between June 2020 and August 2021 in our hospital. Five hundred and fifty-three patients with ureteral stones participated in the validation cohort from September 2020 to April 2022. The data were prospectively recorded. Backward stepwise selection was applied using the likelihood ratio test with Akaike's information criterion as the stopping rule. The efficacy of this predictive model was assessed concerning its clinical usefulness, calibration, and discrimination. Finally, 7.2% (110/1522) of patients in the development cohort and 8.7% (48/553) of those in the validation cohort suffered from major complications. We identified five predictive factors for major complications: age, gender, stone size, Hounsfield unit of stone, and hydronephrosis. This model showed good discrimination with an area under the receiver operating characteristic curves of 0.885 (0.872-0.940) and good calibration (P = 0.139). The decision curve analysis showed that the model was clinically valuable. In this large prospective cohort, we found that older age, female gender, higher Hounsfield unit, size, and grade of hydronephrosis were risk predictors of major complications after SWL. This nomogram will be helpful in preoperative risk stratification to provide individualized treatment recommendations for each patient. Furthermore, early identification and appropriate management of high-risk patients may decrease postoperative morbidity.

Semirigid Ureteroscopy Therapy against Childhood Kidney Stones

Objective

The purpose of the current study was to assess the effectiveness of semirigid ureterorenoscopy (URS) as first-line therapy for early childhood patients with <20 mm stones in the pelvic, middle, or upper calices.

Methods

In all, 61 pediatric kidney stone patients who had flexible ureteroscopy (fURS) between January 1, 2010, and December 31, 2019, were included in this study. Before fURS, semirigid URS employed the UreTron or holmium: YAG (Ho : YAG) laser was conducted. When semirigid URS was unsuccessful, fURS was used for retrograde intrarenal surgery (RIRS). All participants were monitored clinically for a minimum of three months after each procedure.

Results

The patient's mean age was 4.52 ± 1.53 years, and 52 (83.61%) participants underwent semirigid URS successfully. Mean procedural duration of semirigid URS was 36.49 ± 7.72 min. The stone-free rate after semirigid URS was 92.16% (47/51). During the postprocedural medical observation, there were no serious adverse effects.

Conclusions

Based on the present study's findings, semirigid URS is a low-risk, effective therapy for kidney stones in selected pediatric patients.

Large spontaneous steinstrasse: Our experience and management issues in tertiary care centre

BACKGROUND

Steinstrasse, is described as array of stone pieces in the ureter following extracorporeal shock wave lithotripsy (SWL). It is well-recognized, transient event. Steinstrasse clears spontaneously, however about 6% require intervention. Spontaneous steinstrasse without prior history of SWL is a rare occurrence and only few case reports are published in literature. Objective of the study was to assess the aetiology and management issues of large spontaneous steinstrasse in our centre.

METHOD

From February 2017 to March 2019, 684 patients underwent SWL for renal or ureteric stones. Twenty-eight patients presented with steinstrasse of which nine patients had no prior history of SWL. Detailed clinical profile and management issues have been discussed.

RESULT

Among the nine patients of spontaneous steinstrasse, there were six males and three females. Mean age of the patients was 39 years (±13 years SD). Bilateral large spontaneous steinstrasse was seen in one out of nine patients. Seven patients had associated renal stones. Five patients presented with obstructive uropathy and three out of them had urosepsis as initial presentation. Ureterolithotomy and percutaneous nephrolithotomy were commonly performed procedures for stone clearance. Metabolic work was done in all cases in follow up period. Three patients had hypercalciuria and hypocitraturia suggestive of renal tubular acidosis.

CONCLUSION

Large spontaneous steinstrasse is uncommon case scenario. It can be subtle in presentation and yet have significant patient consequence in terms of renal function and infection. Prompt management is essential to preclude permanent loss of renal function. Metabolic evaluation is indispensable in such cases.

Alpha-blockers after shock wave lithotripsy for renal or ureteral stones in adults

BACKGROUND

Shock wave lithotripsy (SWL) is a widely used method to treat renal and ureteral stone. It fragments stones into smaller pieces that are then able to pass spontaneously down the ureter and into the bladder. Alpha-blockers may assist in promoting the passage of stone fragments, but their effectiveness remains uncertain.  OBJECTIVES: To assess the effects of alpha-blockers as adjuvant medical expulsive therapy plus usual care compared to placebo and usual care or usual care alone in adults undergoing shock wave lithotripsy for renal or ureteral stones.

SEARCH METHODS

We performed a comprehensive literature search of the Cochrane Library, the Cochrane Database of Systematic Reviews, MEDLINE, Embase, several clinical trial registries and grey literature for published and unpublished studies irrespective of language. The date of the most recent search was 27 February 2020.

SELECTION CRITERIA

We included randomized controlled trials of adults undergoing SWL. Participants in the intervention group had to have received an alpha-blocker as adjuvant medical expulsive therapy plus usual care. For the comparator group, we considered studies in which participants received placebo.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies for inclusion/exclusion, and performed data abstraction and risk of bias assessment. We conducted meta-analysis for the identified dichotomous and continuous outcomes using RevManWeb according to Cochrane methods using a random-effects model. We judged the certainty of evidence on a per outcome basis using GRADE.

MAIN RESULTS

We included 40 studies with 4793 participants randomized to usual care and an alpha-blocker versus usual care alone. Only four studies were placebo controlled. The mean age of participants was 28.6 to 56.8 years and the mean stone size prior to SWL was 7.1 mm to 13.2 mm. The most widely used alpha-blocker was tamsulosin; others were silodosin, doxazosin, terazosin and alfuzosin.  Alpha-blockers may improve clearance of stone fragments after SWL (risk ratio (RR) 1.16, 95% confidence interval (CI) 1.09 to 1.23; I² = 78%; studies = 36; participants = 4084; low certainty evidence). Based on the stone clearance rate of 69.3% observed in the control arm, an alpha-blocker may increase stone clearance to 80.4%. This corresponds to 111 more (62 more to 159 more) participants per 1000 clearing their stone fragments. Alpha-blockers may reduce the need for auxiliary treatments after SWL (RR 0.67, 95% CI 0.45 to 1.00; I² = 16%; studies = 12; participants = 1251; low certainty evidence), but also includes the possibility of no effect. Based on a rate of auxiliary treatments in the usual care arm of 9.7%, alpha-blockers may reduce the rate to 6.5%. This corresponds 32 fewer (53 fewer to 0 fewer) participants per 1000 undergoing auxiliary treatments. Alpha-blockers may reduce major adverse events (RR 0.60, 95% CI 0.46 to 0.80; I² = 0%; studies = 7; participants = 747; low certainty evidence). Major adverse events occurred in 25.8% of participants in the usual care group; alpha-blockers would reduce this to 15.5%. This corresponds to 103 fewer (139 fewer to 52 fewer) major adverse events per 1000 with alpha-blocker treatment. None of the reported major adverse events appeared drug-related; most were emergency room visits or rehospitalizations. Alpha-blockers may reduce stone clearance time in days (mean difference (MD) -3.74, 95% CI -5.25 to -2.23; I² = 86%; studies = 14; participants = 1790; low certainty evidence). We found no evidence for the outcome of quality of life. For those outcomes for which we were able to perform subgroup analyses, we found no evidence of interaction with stone location, stone size or type of alpha-blocker. We were unable to conduct an analysis by lithotripter type. The results were also largely unchanged when the analyses were limited to placebo controlled studies and those in which participants explicitly only received a single SWL session.

AUTHORS' CONCLUSIONS

Based on low certainty evidence, adjuvant alpha-blocker therapy following SWL in addition to usual care may result in improved stone clearance, less need for auxiliary treatments, fewer major adverse events and a reduced stone clearance time compared to usual care alone. We did not find evidence for quality of life. The low certainty of evidence means that our confidence in the effect estimate is limited; the true effect may be substantially different from the estimate of the effect.

Minimally Invasive Management of Uroliths in Cats and Dogs

Urolithiasis commonly affects cats and dogs. The American College of Veterinary Internal Medicine established guidelines for the treatment of uroliths that reflect modern techniques prioritizing minimally invasive procedures with an emphasis on prevention strategies to limit morbidity and mortality. Extracorporeal shockwave lithotripsy and endoscopic nephrolithotomy constitute some of the minimally invasive treatment modalities available for upper urinary tract uroliths. Cystoscopic-guided basket retrieval, cystoscopic-guided laser lithotripsy, and percutaneous cystolithotomy are minimally invasive options for the management of lower urinary tract uroliths. Following stone removal, prevention strategies are essential to help reduce morbidity and mortality associated with stone recurrence.

Urethral Steinstrasse following Laser Lithotripsy of Prostatic Urethral Calculi

Symptomatic prostatic calculi are rare occurrences with several management options, the most popular of which is currently transurethral laser lithotripsy. This is a generally well-tolerated procedure with minimal complications. To date, no reported episodes of steinstrasse at the urethral level following prostatic calculi lithotripsy have been documented to our knowledge. We report a unique case of acute urinary retention secondary to obstructive calculi fragments following a transurethral laser lithotripsy of large prostatic calculi, further complicated by stricture at the fossa navicularis.

POSSIBILITIES TO IMPROVE THE THERAPY OF THE PATIENTS WITH URETERAL CONCRETIONS

The aim of the given study was to improve the results of treatment of patients with concretions of the upper third of the ureter. Materials and methods. The clinical trial was carried out as a non-interventional open, controlled, in two groups of patients with baseline control. The inclusion criteria concerned the patients with concretions of the upper third of the ureter 0.7-0.9 mm in size, which had one session of an extracorporeal shock-wave lithotripsy (ESWL), and after the procedure the size of the concretions fragments was up to3 mm. The study involved 60 patients, all patients in the main group (n = 30) were treated using phytotherapy, within 1 month starting with basic therapy under hospital conditions and continuing with preventative treatment in an outpatient setting. The control group (n = 30) received baseline therapy (up to 10 days) at the stationary stage. Results and discussion. In patients of the main group, fragments of concretions came out significantly faster, namely: in the main group, the fragments came out in 21 patients (70.0 %), while in the control group in 15 patients (50.0 %) (p1- p2, p <0.05) to the 7th day, and in the main group, the fragments came out in one patient more than 14 days, and in the control group – in 5 patients, p <0.05. The "stone path" in the bottom third of the ureter was in 1 patient (3.3 %) of the main group and in 3 patients (10.0 %) in the control group (p1-p2, p <0.05). The "stone path" departure time in patients of the main group was 2 days, and in patients of the control group it was 4.1 days from the time of its formation (p1-p2, p <0.05). Bacteriuria was observed in the main group on the 10th day 6.6 % less relative to the control group. Conclusion. At comparing the obtained results in patients of both groups in 1 month it was noted that high efficacy of the treatment was registered in 6 (20 %) patients of the main group and in 3 patients (10 %) of the control group (p <0.05), moderate efficiency was registered in 23 (76.7 %) patients of the main group and in 22 (73.3 %) patients of the control group respectively, low efficacy was registered in 1 (3.33 %) patient in the main group and 5 (16.7 %) patients of the control group (p <0,05), which points to the effectiveness of Urolesan capsules use in complex therapy of patients with concretions of the one third of ureter.

[S2k guidelines on diagnostics, therapy and metaphylaxis of urolithiasis (AWMF 043/025) : Compendium]

Every tenth German citizen will suffer from at least one urinary calculus during the lifetime. The diagnostics, treatment and follow-up treatment of urolithiasis are, therefore, part of the daily routine practice for all urologists in hospitals and private practices as well as in many other disciplines, such as general practitioners, internists, nephrologists and pediatricians. Although the diagnostics and therapy have experienced substantial alterations over the last 10 years, the possibilities of metabolic diagnostics and secondary prevention for patients at risk are, unfortunately and unjustly, in many places very poorly represented. The present S2k guidelines, which for the first time were established in an interdisciplinary consensus process, represent the current practical recommendations and, whenever possible, use tables and algorithms in order to facilitate easy reference in the routine daily work. Last but not least, this greatly simplifies the measures for metaphylaxis.

Can we predict the need for intervention in steinstrasse following shock wave lithotripsy?

Introduction:

Steinstrasse (SS) is a known complication of shock wave lithotripsy (SWL). Although the majority of SS clears spontaneously, about 6% require intervention. This study was carried out to identify the factors that determine the need for intervention in SS.

Materials and Methods:

This was a retrospective study of all patients who developed steinstrasse following SWL at our center. They were divided into two groups: a) Those cleared spontaneously and b) Those required intervention. The two groups were compared with regard to demographic profile, stone factors and factors related to steinstrasse.

Results:

Out of 2436 cases of SWL, 89 (3%) formed steinstrasse. The majority of the patients (35%) who required intervention had stone sizes of 10-14 mm. Coptcoat type III steinstrasse required significantly more interventions for clearance (P = 0.001). The site and the size of the SS was not a predictor of intervention for SS.

Conclusions:

Early intervention is warranted in patients with steinstrasse where the lead fragment is >5 mm (Coptcoat type III).

Successful evacuation of large perirenal hematoma after extracorporeal shock wave lithotripsy (ESWL) - step 1 of the IDEAL recommendations of surgical innovation

Larger perirenal hematomas after extracorporeal shock wave lithotripsy (ESWL) are sometimes related to the loss of renal function due to compression of the normal renal tissue. After computed tomography-guided drainage and locally applied urokinase, the hematoma was fractionally evacuated. This procedure is a save and fast way to recover normal renal function.

A low or high BMI is a risk factor for renal hematoma after extracorporeal shock wave lithotripsy for kidney stones

The purpose of this study was to evaluate risk factors for renal hematoma after extracorporeal shock wave lithotripsy (SWL) for kidney stones in a matched case-control analysis of a subgroup of patients recruited from a prospective randomized cohort. Between 06/2010 and 03/2013, 418 patients underwent SWL with the MODULITH^®-SLX-F2-lithotripter for kidney stones. In 39/418 patients (9 %), ultrasound at post-treatment day 1 revealed renal hematomas. For 37 of these patients, a matched group without hematoma could be selected according to the following matching criteria: age, gender, number and energy of shock waves, stone burden and localization. Risk factors for renal hematoma after SWL were compared between the two groups. The rates of diabetes, stopped anticoagulant/antiplatelet medications and arterial hypertension were not different between the two groups (p > 0.2). The skin-kidney distance was virtually the same in both groups (p = 0.5). In the hematoma group, significantly more patients had a high (>30: n = 16) as well as a low (<21.5: n = 4) BMI when compared to the control group (n = 4; n = 0; p < 0.001). Importantly, all patients with BMI <21.5 developed renal hematomas after SWL. Patients with a high (>30) or low (<21.5) BMI had a higher risk for renal damage after SWL. Therefore, alternative endoscopic treatment options should be considered in these patients.

MiniJFil®: A New Safe and Effective Stent for Well-Tolerated Repeated Extracorporeal Shockwave Lithotripsy or Ureteroscopy for Medium-to-Large Kidney Stones?

Background

Percutaneous nephrolithotomy (PCNL) is recommended for treating staghorn stones or stones measuring > 20 mm. Extracorporeal shockwave lithotripsy (ESWL) or flexible ureteroscopy (URS) may be used as a complement. However, PCNL can cause trauma to the kidney parenchyma, and patients may find a noninvasive procedure, such as ESWL, to be more attractive.

Objectives

The aim of this study was to evaluate the clinical efficiency of MiniJFil® stenting associated with ESWL or second-line URS for the treatment of medium-to-large kidney stones. The MiniJFil® is a stent reduced to a suture of 0.3F attached to a renal pigtail. The entire ureter is occupied only by the suture of the stent.

Methods

We retrospectively analyzed the data of 28 patients. Twenty-four patients had kidney stones measuring > 15 mm (group 1) and four patients had staghorn stones (group 2). All of the patients were fitted with MiniJFil® 2 - 3 weeks before any treatment. ESWL was always our first-line therapy. Stone-free (SF) status was defined as no evidence of stones.

Results

In group 1, the mean largest and cumulative stone diameters, respectively, were 18.7 ± 5.7 mm and 45.0 ± 12.0 mm. In group 2, the mean volume was 6,288.4 ± 2,733.0 mm³. The overall SF was 96.4% (100% for group 1 and 75% for group 2). The mean number of sessions of ESWL and URS, respectively, was 1.4 ± 0.7 and 0.8 ± 0.9 in group 1 and 4.0 ± 2.0 and 1.5 ± 1.3 in group 2. The mean times to achieve these rates were 3.2 ± 1.7 months and 5.6 ± 2.3 months for groups 1 and 2, respectively. One patient in group 2 was treated with only three sessions of ESWL. Renal colic was observed in only five patients (17.9%).

Conclusions

MiniJFil® stenting is safe and may be an alternative for the treatment of kidney stones during minimally invasive procedures.

Risk factors for formation of steinstrasse after extracorporeal shock wave lithotripsy for pediatric renal calculi: a multivariate analysis model

OBJECTIVES

To define various stone, renal and therapy factors that could affect steinstrasse (SS) formation after extracorporeal shock wave lithotripsy (SWL) for pediatric kidney stones. Thus, SS could be anticipated and prophylactically avoided

METHODS

From January 1999 through December 2012, 317 children underwent SWL with Dornier Lithotripter S for the treatment of renal stones. Univariate and multivariate statistical analyses of patients, stones and therapy characteristics in relation to the incidence of SS were performed to detect the factors that had a significant impact on SS formation.

RESULTS

The overall incidence of SS was 8.5%. The steinstrasse was in the pelvic ureter in 74.1% of the cases, lumbar ureter in 18.5% and iliac ureter in 7.4%. Steinstrasse incidence significantly correlated with stone size, site and age of child. Steinstrasse was more common with increasing stone length and stones located in renal pelvis or upper calyx with the age below 4 years. A statistical model was constructed to estimate the risk of steinstrasse formation accurately. The equation for logistic regression is Z = -4.758 + B for age + B for size stone X length in mm + B for stone site.

CONCLUSIONS

The stone size, site and age are the most important risk factors responsible for SS formation in children. Our regression analysis model can help with prospective identification of children who will be at risk of SS formation. Those children at high risk of SS formation should be closely monitored or treated by endoscopic maneuvers from the start.

Efficacy of extracorporeal shock wave lithotripsy in pediatric and adolescent urolithiasis

PURPOSE

To retrospectively evaluate the efficacy of extracorporeal shock wave lithotripsy (ESWL) by age and current condition as a first-line treatment for pediatric and adolescent urolithiasis.

MATERIALS AND METHODS

The computerized records of 55 children were retrospectively reviewed from March 1991 to July 2007. The children were below 18 years of age and had undergone ESWL monotherapy for urolithiasis. There were 36 boys (65.5%) and 19 girls (34.5%), with a mean age of 8.5 years (range, 0.5-18 years). There were 24 patients aged 7 years or less and 31 patients aged more than 7 years.

RESULTS

The mean size of the stones was 9.48 mm (range, 4-22 mm). The overall success rate of ESWL was 90.9% (50 children). The mean number of ESWL sessions was 2.02 (range, 1-10). The mean number of ESWL sessions for the patient group aged 7 years or less was 1.16 (range, 1-2) and that for the patient group aged more than 7 years was 2.97 (range, 1-10; p=0.037). There was also a statistically significant difference in the mean number of ESWL sessions between the younger and older patients who needed general anesthesia (1.16 vs. 2.2 sessions, respectively; 0.042).

CONCLUSIONS

In the patient group aged 7 years or less, the number of ESWL sessions and the complication rate were comparable with those for endoscopic management. Thus, ESWL is an effective first-line treatment modality for patients aged less than 7 years.

Retrograde intrarenal surgery for the treatment of renal stones in patients with a solitary kidney

OBJECTIVE

To evaluate the efficacy and safety of retrograde intrarenal surgery (RIRS) in the treatment of renal stones in patients with a solitary kidney.

MATERIALS AND METHODS

From December 2008 to March 2012, 24 patients with a solitary kidney who were treated with RIRS for renal stones were included in the study. All patients were preoperatively evaluated with urine culture, serum biochemistry, urinary ultrasonography, noncontrast computed tomography or intravenous urography, or both. The procedure was considered as successful in patients with complete stone disappearance or fragments <4 mm on computed tomography. Preoperative, operative, and postoperative data of the patients were retrospectively analyzed. The mean serum creatinine levels before and after the procedures were compared using a paired sample t-test.

RESULTS

The study included 24 patients with a mean age of 44.41 ± 12.15 years (range, 24-70). The mean stone size was 19.83 ± 5.90 mm (range, 10-35). The mean operative time was 55.83 ± 10.90 minutes (range, 40-75). The success rates were 83.3% and 95.8% after the first and second procedures, respectively. A pigtail stent was placed in all patients. The mean serum creatinine levels before the procedures and at 2 weeks after removal of the pigtail stents were 1.54 ± 0.55 mg/dL (range, 0.7-2.8) and 1.56 ± 0.50 mg/dL (range, 0.9-2.6), respectively (P = .92). Minor complications, classified as Clavien I or II, occurred in 4 patients (16.6%). No major complications (Clavien III-V) occurred in the study group.

CONCLUSION

RIRS is an effective and safe procedure that can be used to manage renal stones in patients with a solitary kidney.

Effect of size and site on the outcome of extracorporeal shock wave lithotripsy of proximal urinary stones in children

OBJECTIVE

To determine the effect of location and size of stones on the outcome of extracorporeal shock wave lithotripsy (ESWL) in children.

PATIENTS AND METHODS

In 2008-2010, 150 children (median age 6.6 years) with radio-opaque ureteric and renal stones measuring ≤4 cm were treated. Exclusion criteria were coagulation disorders, pyelonephritis, distal obstruction, non-functioning kidney and hypertension. ESWL was performed under general anesthesia. Follow up period was 5-22 months.

RESULTS

186 stones were treated: 76 calyceal, 92 pelvic and 18 proximal ureteral. Mean stone size was 1.3 cm. A total of 312 sessions were performed (mean per stone = 1.67 sessions). The mean number of shock waves per session was 2423.68. Overall stone-free rate was 89.24%. Having a calyceal location did not significantly affect the stone-free rate (p = 0.133). The failure rate was significantly higher (66.7%) in stones >3 cm in size (p < 0.001). Complications were encountered in 18 patients; 2 underwent auxillary ureteroscopy and 4 uretrolithotomy for treatment of steinstrasse.

CONCLUSION

ESWL is a safe and effective method for treatment of stones up to 2 cm in children. Rate of auxillary procedures increases in stones >2 cm in size. About 80% of failures were associated with stone size >1.35 cm while 52.3% of completely cleared stones were associated with size <1.35 cm.

Efficacy of alfuzosin after shock wave lithotripsy for the treatment of ureteral calculi

PURPOSE

We evaluated the efficacy of alfuzosin for the treatment of ureteral calculi less than 10 mm in diameter after extracorporeal shock wave lithotripsy (ESWL).

MATERIALS AND METHODS

A randomized, single-blind clinical trial was performed prospectively by one physician between June 2010 and August 2011. A total of 84 patients with ureteral calculi 5 to 10 mm in diameter were divided into two groups. Alfuzosin 10 mg (once daily) and loxoprofen sodium 68.1 mg (as needed) were prescribed to group 1 (n=41), and loxoprofen sodium 68.1 mg (as needed) only was prescribed to group 2 (n=44). The drug administration began immediately after ESWL and continued until stone expulsion was confirmed up to a maximum of 42 days after the procedure.

RESULTS

Thirty-nine of 41 (95.1%) patients in group 1 and 40 of 43 (93.0%) patients in group 2 ultimately passed stones (p=0.96). The number of ESWL sessions was 1.34±0.65 and 1.41±0.85 in groups 1 and 2, respectively (p=0.33). The patients who required analgesics after ESWL were 8 (19.5%) in group 1 and 13 (30.2%) in group 2 (p=0.31). Visual analogue scale pain severity scores were 5.33±1.22 and 6.43±1.36 in groups 1 and 2, respectively (p=0.056). The time to stone expulsion in groups 1 and 2 was 9.5±4.8 days and 14.7±9.8 days, respectively (p=0.005). No significant adverse effects occurred.

CONCLUSIONS

The use of alfuzosin in combination with ESWL seems to facilitate stone passage and to reduce the time of stone expulsion but does not affect the stone-free rate.

Predictive factors and management of steinstrasse after shock wave lithotripsy in pediatric urolithiasis--a multivariate analysis study

OBJECTIVE

To define the predictive factors for the formation of steinstrasse (SS) after shock wave lithotripsy (SWL) and determine the treatment strategies for this complication in pediatric urolithiasis.

METHODS

We retrospectively reviewed the data of 341 renal units (RUs) treated with SWL for urolithiasis. The stone location, stone burden, auxiliary procedures, energy level, and number of shock waves were recorded. Statistical analysis was performed to detect the predictive factors for the formation of SS. In addition, the treatment of children with SS was evaluated.

RESULTS

The mean age of the children was 8.31 years (range 1-17). Episodes of SS developed in 26 RUs (7.6%). Of the 26 RUs, 20 (77%) were localized in the lower, 5 (19%) in the upper, and 1 (4%) in multiple locations in the ureter. The stone burden was the only statistically significant factor predicting the formation of SS on logistic regression analysis (P = .001). Of the 26 RUs, 17 (65.4%) were successfully managed by repeat SWL monotherapy, 4 (15.4%) were managed with ureteroscopy after failure of SWL, 1 (3.8%) was managed by ureteroscopy monotherapy, and 4 (15.4%) were monitored with conservative management with antispasmodic drug plus hydration therapy. The mean number of SWL sessions was 1.72.

CONCLUSION

The incidence of SS development in children after SWL treatment was similar to that in adult series. Our results suggest that the stone burden is a significant predictive factor for the development of SS after SWL in pediatric urolithiasis. Most children with SS could be easily and safely treated by repeat SWL.

Fragmentation without extraction in ureteral stones: outcomes of 238 cases

We aimed to evaluate the success rates, auxiliary procedures and complications after ureteroscopic lithotripsy (URS) during which the fragments left in situ for spontaneous passage after complete disintegration into a acceptable (<4 mm) size. 238 patients with ureteral stones were treated with URS between 2005 and 2011, and disintegrated fragments (<4 mm) were left in situ for spontaneous passage. Patients were followed with radiography for 3 months and evaluated with respect to the success rates (stone-free), auxiliary procedures, complication rates and additional analgesic requirement. The median age was 42.2 ± 13.7 years, and overall stone size was 8.79 ± 2.94 mm. Significantly lower rate of stone-free status was achieved in proximal stones (p < 0.05). A second URS was necessary in 5% (n = 12) of the patients. Double-J catheter placement during initial URS did not cause any change in the rate of secondary URS (p = 0.620). Additional oral or intramuscular analgesia was required in 41% (n = 97) and 25% (n = 59) of the patients, respectively, after discharge. The overall stone-free rate was 95% and mean time to complete clearance was 5 days. Severe colic pain within 24 h was noted in 21 (9%), and transient hydro-ureteronephrosis in 31 (13%) patients, as minor complications. Leaving the fragments (<4 mm) in place for spontaneous passage following a successful disintegration in URS could be a reasonable approach with acceptable and comparable stone-free rates, and this approach appears to give chance of shortening the duration of operation and also avoiding from the potential morbidity of repeated manipulations during the both further disintegration and extraction.

Steinstrasse predictive factors and outcomes after extracorporeal shockwave lithotripsy

PURPOSE

Urinary stone disease is a common medical problem. Extracorporeal shockwave lithotripsy (SWL) has been applied with high success and low complication rates. Steinstrasse (SS) is a possible complication after SWL. The aim of the present study was to prospectively evaluate the factors and outcomes associated with SS after SWL.

MATERIALS AND METHODS

We have prospectively evaluated 265 SWL sessions (2005-2009). Two lithotriptors were used randomly: Siemens Lithostar and Dornier Compact S. All patients had imaging exams after 30 and 90 days or according to symptoms.

RESULTS

SS was observed in 14 (5.3%) out of 265 SWL procedures (n = 175 patients, 51.5% women/48.5% men, mean ± SD age = 46.3 ± 15.5 years). SS was more common after SWL for pelviureteral calculi rather than caliceal stones (p = 0.036). There was a trend toward more occurrences of SS after SWL for larger stone area (> 200 mm², p = 0.072). Preoperative ureteral stent didn't prevent SS. SWL machine, intensity, number of pulses and frequency were not associated with SS formation. Post-SWL pain, fever and gravel elimination were factors associated with SS (p = 0.021; p = 0.011; p = 0.078). When SS occurred, treatment modalities included Medical Expulsive Therapy (MET), ureteroscopy and SWL.

CONCLUSIONS

Steinstrasse is an uncommon event after SWL and seems to occur more frequently with larger pelviureteral stones. Impaction of stones is more frequent in the middle ureter. All patients should be followed after SWL, but SS should be specially suspected if there is macroscopic gravel elimination, flank pain and/or fever. When SS occurs, treatment should be promptly introduced, including medical expulsive therapy, surgical approach or SWL in selected cases. Further prospective studies are awaited to evaluated preventive measures for SS occurrence.

Three-dimensional assessment of urinary stone on non-contrast helical computed tomography as the predictor of stonestreet formation after extracorporeal shock wave lithotripsy for stones smaller than 20 mm

The incidence of stonestreet formation after extracorporeal shock wave lithotripsy (ESWL) rises with increasing stone burden. However, stonestreet after ESWL is often experienced even in stones smaller than 20 mm. To examine whether the non-contrast helical computed tomography (CT) data could predict stonestreet formation in these stones, 53 radiopaque stones of 5-20 mm treated with ESWL were evaluated. Maximal dimension was measured on plain radiograph. From an attenuation value histogram graphed from the CT data, total stone volume and mean attenuation value were calculated. Seven stonestreets longer than 25 mm developed. There was no significant difference in maximal dimension and total stone volume between stones that did and stones that did not develop stonestreet. Mean attenuation value was the sole significant predictive factor. Application of mean attenuation value with cut-off level of 650 HU would anticipate stonestreet formation with a sensitivity of 85.7% and a specificity of 71.7%. The estimated risk of stonestreet formation is high in the treatment of stones with higher mean attenuation value.

Treatment Selection and Outcomes: Renal Calculi

This article summarizes the history of how renal stones have been treated over the centuries and reviews current treatments and outcomes for renal stones. The authors provide an algorithm based on available outcome data for shock wave lithotripsy, ureteroscopy, and percutaneous nephrolithotomy.

Extracorporeal shock wave lithotripsy in children: evaluation of the results considering the need for auxiliary procedures

OBJECTIVE

To retrospectively evaluate the efficacy of extracorporeal shock wave lithotripsy (ESWL) in children with renal stones, with regard to ability of ureters to transport the fragments, and need for adjunctive procedures.

PATIENTS AND METHODS

Between January 2000 and November 2004, 60 children (24 girls and 36 boys) with a total of 72 stones of the upper urinary tract were treated by ESWL using a PCK V5 lithotriptor. Patients with anatomical abnormalities and staghorn stones were excluded from the study. Stone size ranged from 4 to 28 mm. Mean number of shock waves was 1430 (range 600-2000) per ESWL session and mean energy used for stone disintegration was 12 kV (range 6-18). At 24-48 h after ESWL, a plain film or renal ultrasound was obtained to evaluate stone fragmentation.

RESULTS

Our stone-free rate after one session of ESWL was 92.8% and 81.2% for patients with stones smaller than 10mm and stones between 10 and 28 mm, respectively. Seven (11.6%) patients developed distal ureteral steinstrasse, and the stone size was 15-20 mm and 20-28 mm in two and five patients, respectively. The steinstrasse completely cleared under meticulous follow-up. No patient needed an adjunctive procedure, such as a double-J stent or nephrostomy tube placement, or ureteroscopic stone manipulation.

CONCLUSION

A child's ureter is capable of transporting the fragments after lithotripsy. Interventional procedures should be a last resort. Expectant management is usually adequate even in patients who develop steinstrasse after ESWL.

Stepwise shock wave lithotripsy: Results of initial study for the treatment of urinary stones in childhood

OBJECTIVE

To assess the effectiveness of stepwise extracorporeal shock wave lithotripsy in the treatment of upper urinary stones in childhood.

PATIENTS AND METHODS

Between August 1998 and August 2003, 31 patients were treated for renal or ureteric stones. All treatments were performed with Dornier Compact Delta lithotripter. The number of shock wave was limited to maximum 3000 shock waves/session. The voltage was started at 10 kV and increased stepwise to 12.75 kV. Stone clearance was assessed at 3 months. The stone free state was defined as the absence of stone fragments.

RESULTS

Total 31 stones (24 renal and 7 ureteral stones) were treated. The age of the patients was median 8 (min-max: 0.8-12) years. The length of the stones was median 1 (min-max: 0.5-1.5) cm for renal stones and median 0.5 (min-max: 0.5-1) cm for ureteral stones. As an auxiliary procedure, open pyelolithotomy was required for 1 patient. The overall stone free rates for renal and ureter stones were 79% and 100%, respectively. Post-treatment insignificant hematuria was observed in all cases.

CONCLUSION

Stepwise shock wave lithotripsy was an effective procedure for the treatment of urinary calculi in childhood.

[Extra corporeal shock wave lithotripsy (ESWL) procedure in urology]

Since 1980, extra corporeal shock wave lithotripsy (ESWL) has become the first line treatment for most stones in adults and children. The indications are based on criteria depending on localization, chemical composition and size of the renal and ureteral calculi. Since the DORNIER HM 3 which remains the gold standard of first generation lithotripters, many devices of second and third generation have been built (electro hydrolic, piezo electric and electromagnetic) with fluoroscopic and ultrasound localization systems. SWL may now be performed on an out-patient basis without anaesthesia or under neuroleptic analgesia. Indications and evaluation criteria on 3 months plain abdominal X-ray are better defined since 1996. Nevertheless, comparison of reported results remains difficult due to the multiplicity of lithotripter types and the lack of consensus on efficacy criteria. Today, the third generation of mobile electromagnetic lithotripters give an average of 80% stone free rate of patients with kidney and ureteral calculi whatever the localization and size.

Renal pelvic stones: choosing shock wave lithotripsy or percutaneous nephrolithotomy

Introduction of minimally invasive techniques has revolutionized the surgical management of renal calculi. Extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy are now both well-established procedures. Each modality has advantages and disadvantages, and the application of each should be based on well-defined factors. These variables include stone factors such as number, size, and composition; factors related to the stone's environment, including the stone's location, spatial anatomy of the renal collecting system, presence of hydronephrosis, and other anatomic variables, such as the presence of calyceal diverticula and renal anomalies; and clinical or patient factors like morbid obesity, the presence of a solitary kidney, and renal insufficiency. The morbidity of each procedure in relation to its efficacy should be taken in to account. This article will review current knowledge and suggest an algorithm for the rational management of renal calculi with shock wave lithotripsy and percutaneous nephrolithotomy.

[Extracorporeal shock-wave lithotripsy. An established treatment]

Extracorporeal shock wave lithotripsy (ESWL) is the most required urinary stone therapy in our country and in the rest of the world. In a way it has replaced the alternative treatments (open surgery, percutaneous nephrolithectomy, ureteroscopy). Nevertheless these therapeutic approaches have still its own indications. Although there is no a definitive agreement, it should be desirable a world-wide consensus where each therapy will have a exactly defined land with all potential of each management improved. We review ESWL technical aspects, its literature-based most accepted indications, adverse bioeffects and last, future improvements are considered.