Management of upper urinary tract calculi with ureteroscopic techniques

Analyzing global research trends and focal points in the utilization of laser techniques for the treatment of urolithiasis from 1978 to 2022: visualization and bibliometric analysis

Laser lithotripsy is gaining global prominence and is a dynamically progressing field marked by a continual influx of new and comprehensive research each year. Recently, there has been a noticeable shift toward the adoption of various kinds of lasers, such as holmium: yttrium-aluminum-garnet (Ho:YAG) and thulium fiber (TFL) lasers. Consequently, we aim to conduct a bibliometric analysis to analyze key areas of research activity within scientific publications that center on the utilization of laser techniques in urolithiasis. A search of the literature spanning from 1978 to 2022 was carried out on 25 December 2023 using the Scopus database to explore research related to the application of laser techniques for urolithiasis treatment. Visualization analysis was performed using VOSviewer software (version 1.6.20). We examined 962 publications that met the specified criteria, 791 (82.22%) of which were original articles. The analysis of the retrieved publications indicated a consistent increase in research output from 1978 to 2022; a particularly noteworthy surge occurred after 2003. In particular, the U.S. claimed the leading position as the most productive country, contributing 211 articles (21.93%). However, India had the highest research productivity according to the adjustment index of 19.08. In the European region, 324 publications (33.68% of the total) originated from 25 countries. The Journal of Endourology contributed the most between 1978 and 2022 (n = 96, 9.98%). The most cited paper examined the effectiveness of holmium: yttrium-aluminum-garnet (Ho:YAG) lasers, while a subsequent study focused on the use of a thulium fiber laser (TFL), an emerging laser technology that has gained increased recognition. Co-occurrence analysis revealed three distinct clusters focusing on the types of laser technology, minimally invasive approaches, and success rate/postoperative complications. This comprehensive investigation delves into the global landscape of laser use for the treatment of urolithiasis. This review supports the emerging clinical concept of using various types of laser technology for urolithiasis treatment. Moreover, the hot issues that researchers should focus on based on the findings of this study are the use of different types of laser lithotripsy in view of the surgical approach, success rate and complications.

Comparison of immediate versus post-stenting ureteroscopy for ureteral stones treatment

Ureteroscopy is a highly effective treatment for ureteral stones, characterized by a high stone-free rate and a low need for re-treatment. Ureteral stent placement can improve the insertion of the ureteral access sheath and ureteroscope but may be associated with higher morbidity prior to and after ureteroscopy. The study aimed to compare immediate versus post-stenting ureteroscopy for ureteral stone treatment in terms of operative time, intra- and post-operative complications, length of hospital stay, and stone-free rate. This prospective study involved 126 patients with ureteral stones divided into two groups: the post-stenting ureteroscopy group (PS-URS), who underwent primary ureteral stenting by double J followed by delayed ureteroscopy, and the immediate ureteroscopy group (I-URS), who underwent immediate ureteroscopy without previous stenting. Sixty-six patients were included in the PS-URS group and 60 patients in the I-URS group. Results were comparable, with no significant differences between both groups. The mean operative time was 33.77±3.51 minutes for the PS-URS group and 34.60±2.01 minutes for the I-URS group. The average length of hospital stay was 0.84±2.55 days for PS-URS and 0.92±1.96 days for I-URS patients. The stone-free rate was 97% in the PS-URS group and 95% in the I-URS group. The overall complication rate was 4.5% versus 5% in the PS-URS and I-URS groups, respectively, with all complications being minor and managed effectively. Immediate ureteroscopy is a safe and relevant operative approach for ureteral stones, with comparative results for post-stenting delayed ureteroscopy.

Impact of differential ureteral stent diameters on clinical outcomes after ureteroscopy intracorporeal lithotripsy: A systematic review and meta-analysis

In this meta-analysis we assessed whether the diameter of ureteral stents (4.7-5-Fr, 6-Fr) has an impact on the rate of occurrence of urinary tract symptoms and complications after successful URS and intracorporeal lithotripsy. A systematic review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. A rigorous search for relevant studies published in MEDLINE, Embase, and the Cochrane Controlled Trials Register was conducted to find informative randomized controlled trials. The reference lists of relevant articles were also manually searched and reviewed. The protocol was prospectively registered at PROSPERO (CRD42020202164). All statistical evaluations were performed using RevMan software version 5.3.0. Seven articles comprising 547 patients were included in the meta-analysis. After placement of ureteral stents with different diameters for approximately 1 week, we found that ureteral stents with smaller diameters (4.7-5-Fr) were associated with significant improvements in the main domain scores on the Ureteral Stent Symptom Questionnaire, such as urinary symptoms (mean difference -4.47, 95% confidence interval -5.87 to -3.08; P < 0.00001) and body pain (mean difference -2.48, 95% confidence interval -4.37 to -0.59; P = 0.01), but poor outcomes in stent migration compared to ureteral stents with a 6-Fr diameter (odds ratio 3.00, 95% confidence interval 1.06-8.51; P = 0.04). However, there were no significant differences in Ureteral Stent Symptom Questionnaire scores with regard to work performance (mean difference -0.56, 95% confidence interval -2.52 to 1.40; P = 0.58), general health (mean difference -2.29, 95% confidence interval -4.95 to 0.37; P = 0.09), additional problems (mean difference -0.43, 95% confidence interval -1.02 to 0.15; P = 0.15), and complications such as fever (odds ratio 0.75, 95% confidence interval 0.24-2.39; P = 0.63). Ureteral stents with a diameter of 4.7-5-Fr have better outcomes than those with a diameter of 6-Fr, based on the Ureteral Stent Symptom Questionnaire pain and urinary tract symptoms scores. However, they are more prone to migration compared to those with a larger diameter.

Primary versus deferred ureteroscopy for management of calculus anuria: a prospective randomized study

Introduction

Obstructive anuria can be managed by primary ureteroscopy (URS) or deferred URS after initial ureteral stenting. We want to compare the primary URS and deferred URS in the management of calculus anuria regarding the feasibility and clinical outcome.

Material and methods

Between January 2012 and December 2014, 150 patients with anuria due to ureteral calculi were prospectively randomized according to the timing of ureteroscopic intervention into two groups; deferred URS group (69 patients who were treated initially by ureteral stenting) and primary URS group (81 patients who were treated by emergency URS). Follow-up was at least 6 months postoperatively.

Results

Complete stone clearance was 87 % and 75.3% for deferred and primary URS groups, respectively (p = 0.097). Renal function normalized in 94.2% of deferred URS vs. 97.5% of primary URS (p = 0.414). Deferred URS group had a 2.9 % overall complication rate in comparison to 9.9 % for the primary URS group (p = 0.109). Ureteral perforation/pyelonephritis was noted in 6.2% of the primary URS group only (p = 0.043). The median number of maneuvers required until stone clearance was one (range 1–5) for primary URS vs. two (range 2–3) for deferred URS (p <0.001). The cost of primary URS was significantly less (p <0.001). On a multivariate analysis, lower ureteral calculi (OR 13.03, 95% CI 4.07– 41.7, p <0.001) and deferred URS (OR 2.84, 95% CI 1.07–7.49, p = 0.035) were independent predictors for an eventless and successful URS.

Conclusions

Primary URS for calculus anuria is feasible and cost-effective. It has a short hospital stay, but is still technically demanding. The perioperative complications are comparable to URS in normouric patients.

Rirs through Semi-Rigid Ureteroscope and Holmium Laser in the Treatment of Ureteral Stones Retropulsion

Retrograde displacement of ureteral stones into the renal cavities during ureteroscopic lithotripsy represents a frequent and adverse event that leads to additional procedures (ESWL, PCNL, Retrograde Intra-renal lithotripsy with flexible instruments, DJ stent placement and subsequent EWSL) to obtain full clearence of calculi. All these procedures require a further time of treatment.

Between 1/2008 and 3/2009, a total of 48 patients harbouring proximal (21 cases) and distal (27 cases) ureteral stones underwent Holmium Laser lithotripsy. In 3 patients previous percutaneous nephrostomy was performed to drain the excretory way. In 12 cases (25%) stone retropulsion occurred; in 3 patients in the upper calix and in 5 in the renal pelvis. Only in 4 cases the stone migrated in the lower or medium calix. In 8 cases we attempted the immediate treatment of intrarenal displaced stones by advancing the semi-rigid instrument into the renal cavities. In 2 cases the treatment aborted because of the shortness of ureteroscope. The instillation of lubricating lidocaine jelly prevented in 3 cases furher displacement of stone. Washing with saline solution through nephrostomic catheter allowed an effective mobilization of stone and an easy lasertripsy

RIRS was successful in 4 cases. When flexible devices or immediate ESWL are not available, rigid or semi-rigid retrograde lithotripsy with holmium laser immediately performed after ureteral stone displacement represents a safe and effective method to treat displaced stones. Several tricks are required to obtain a good stone-free rate.

Devices to help combat stone retropulsion during ureteroscopic lithotripsy in 2016

Proximal migration of stones during ureteroscopic lithotripsy is a common problem that faces many urologists and reduces stone-free rates, which translates into higher costs and longer operative times. In a bid to increase stone-free rates, there are several anti-retropulsion devices on the market, to help urologists during ureteroscopic lithotripsy. We previously reviewed these anti-retropulsion devices and wish to update what is currently available on the market.

Outcome analysis of holmium laser and pneumatic lithotripsy in the endoscopic management of lower ureteric calculus in pediatric patients: a prospective study

Objective:

To analyse outcomes of holmium laser and pneumatic lithotripsy in treatment of lower ureteric calculus in pediatric patients.

Materials and methods:

Prospective study conducted between August 2013 and July 2015. Inclusion criteria were lower ureteric calculus with stone size ≤1.5cms. Exclusion criteria were other than lower ureteric calculus, stone size ≥1.5cms, congenital renal anomalies, previous ureteral stone surgery. Patients were divided into two groups. Group A underwent pneumatic and group B underwent laser lithotripsy procedure. Patient's baseline demographic and peri-operative data were recorded and analysed. Post operatively X-ray/ultrasound KUB (Kidney, ureter and bladder) was performed to assess stone free status.

Results:

A total of 76 patients who met the inclusion criteria to ureteroscopic intracorporeal lithotripsy were included. Group A and B included 38 patients in each. Mean age was 12.5±2.49 in Group A and 11.97±2.74 years in Group B respectively (p=0.38). Overall success rate was 94.73% in Group A and 100% in Group B, respectively (p=0.87).

Conclusion:

Holmium Laser lithotripsy is as efficacious as pneumatic lithotripsy and can be used safely for the endoscopic management of lower ureteric calculus in pediatric patients. However, holmium laser requires more expertise and it is a costly alternative.

Semi-rigid ureteroscopy: Proximal versus distal ureteral stones

Objective:

To evaluate the safety and efficacy of semi-rigid ureteroscopy in proximal and distal ureteral stones, and to compare the operative and perioperative characteristics between the two stone groups.

Materials and Methods:

We retrospectively reviewed the medical records of patients who underwent semi-rigid ureteroscopy for management of ureteral stones at the International Medical Center between June 2007 and September 2012. All stones were fragmented using Holmium: yttrium-aluminum-garnet (YAG) laser lithotripter. Stones located above the pelvic brim are considered proximal and below it are distal.

Results:

One hundred and ninety-one patients were included. One hundred and three patients (54%) underwent ureteroscopy for proximal stones and 88 (46%) for distal stones. The stone size in the proximal group was 10 mm (±5.5) versus 8.6 mm (±5) in the distal group. The initial stone-free rate for proximal and distal calculi were 89–98.2%, respectively. The perioperative complication rate was higher in the proximal group 10% compared to the distal group which is 1.5% (P = 0.06). Both groups have the same average of hospital stay 1.2 days.

Conclusion:

Although there is a clinical difference between proximal and distal calculi groups in terms of complication and stone-free rates, this difference remained statistically insignificant (P = 0.06). Using a smaller caliber semi-rigid ureteroscopy combined with Holmium-YAG laser can be carried out as a day care procedure and showed a slightly higher risk in patients with proximal ureteral calculi which should be explained to the patient

Significance of Extraction Forces in Kidney Stone Basketing

INTRODUCTION

Ureteroscopic stone extraction devices are effective tools in the management of urolithiasis, but on occasion, their improper use can cause injury to the ureter. Avulsion and perforation of the ureter as a result of excessive forces on the extraction device are some of the more serious complications of this treatment.

MATERIALS AND METHODS

In this article, avulsion and perforation forces were measured by two different test setups. Eleven clinicians were asked to apply three ranges of forces (safe, cautious, and dangerous).

RESULTS

The output force measurements were recorded and plotted for further analysis. The maximal average perforation forces were 7.13±2.36 N in the benchtop tests and 7.07±2.20 N in the ex-vivo porcine tests (P=0.54). The maximal average avulsion forces were measured to be 10.14±2.01 N in the benchtop tests. Although the average forces were similar in the proximal and distal parts of the ureter (P=0.27), higher values were recorded for the distal part. The operative time was noted to be significantly different in the safe and cautious force regions (P=0.006). The average forces were higher in the benchtop tests compared with the porcine ureter tests. The extraction forces were measured and were noted to be significantly different for attending physicians and residents. The results suggest the need for force feedback training for residents.

CONCLUSION

The findings can be used to design a "smart device" that can provide visual force feedback to clinicians while they are operating, leading to improved patient outcome.

Efficacy and safety of Ho:YAG laser lithotripsy for ureteroscopic removal of proximal and distal ureteral calculi

Background

Laser lithotripsy is an established endourological modality. Ho:YAG laser have broadened the indications for ureteroscopic stone managements to include larger stone sizes throughout the whole upper urinary tract. Aim of current work is to assess efficacy and safety of Ho:YAG laser lithotripsy during retrograde ureteroscopic management of ureteral calculi in different locations.

Methods

88 patients were treated with ureteroscopic Ho:YAG laser lithotripsy in our institute. Study endpoint was the number of treatments until the patient was stone-free. Patients were classified according to the location of their stones as Group I (distal ureteric stones, 51 patients) and group II (proximal ureteral stones, 37). Group I patients have larger stones as Group II (10.70 mm vs. 8.24 mm, respectively, P = 0.020).

Results

Overall stone free rate for both groups was 95.8%. The mean number of procedures for proximal calculi was 1.1 ± 0.1 (1–3) and for distal calculi was 1.0 ± 0.0. The initial treatment was more successful in patients with distal ureteral calculi (100% vs. 82.40%, respectively, P = 0.008). No significant difference in the stone free rate was noticed after the second laser procedure for stones smaller versus larger than 10 mm (100% versus 94.1%, P = 0.13). Overall complication rate was 7.9% (Clavien II und IIIb). Overall and grade-adjusted complication rates were not dependant on the stone location. No laser induced complications were noticed.

Conclusions

The use of the Ho:YAG laser appears to be an adequate tool to disintegrate ureteral calculi independent of primary location. Combination of the semirigid and flexible ureteroscopes as well as the appropriate endourologic tools could likely improve the stone clearance rates for proximal calculi regardless of stone-size.

Ureteroscopic lithotripsy in Trendelenburg position for proximal ureteral calculi: a prospective, randomized, comparative study

PURPOSE

We conducted a prospective, randomized, comparative study to compare the clinical outcome between the Trendelenburg position ureteroscopic lithotripsy (tURSL) and the conventional position ureteroscopic lithotripsy (cURSL) for the management of single proximal ureteral stone.

METHODS

From January 2012 to September 2013, consecutive patients with single proximal ureteral calculi less than 2 cm and planned for ureteroscopic lithotripsy at our institution were enrolled in this study. The eligible patients were randomized into cURSL group and tURSL group according to sequence of random numbers generated by computer. In tURSL group, patients were turned into a Trendelenburg lithotomy position with head down 30° while the conventional lithotomy position was applied in cURSL group. URSL was performed using a 6/7.5F semi-rigid ureteroscope with holmium laser. When retropulsion occurred, the stones fragments were followed by semi-rigid ureteroscope up to the renal collecting system. The Olympus P5 flexible ureteroscope was used if there was any suspicion of stone migration into lower calices or incomplete stone fragmentation by semi-rigid ureteroscope. Patients' demographics between the two groups, perioperative course, clinical outcome and complication rates were compared. Data were analyzed using Chi-square test, Fisher's exact test or Student's t test. Binary logistic regression analysis was applied to estimate the effects of surgical position and stone size on stone migration.

RESULTS

A total of 355 cases were finally analyzed in this study (176 in cURSL group and 179 in tURSL group). The mean operative time was significantly prolonged in cURSL group than in tURSL group, while the stone-free rate (SFR) at 4 weeks was significantly higher in tURSL group. A statistically significant difference was found in stone migration rate between the two groups (26.7 vs. 43.6 %, P = 0.001). In the stone migration subsetting, less stones fragments were found to migrate into lower calices in tURSL stone migration subgroup (P = 0.000). Also, the flexible ureteroscope utilization as well as the operative time was significantly decreased in tURSL stone migration subgroup (25.5 vs. 72.3 %, P = 0.000), (44.96 ± 11.0 min vs. 59.17 ± 9.2 min, P = 0.000) with higher SFR after retrograde intrarenal surgery (RIRS) (96.2 vs. 74.5 %, P = 0.000).

CONCLUSION

The tURSL was safe and highly efficacious for the management of proximal ureteral calculus, especially in nonobese patient. Even with important stone migration risk, it rendered higher SFR and less operative time compared with cURSL. Moreover, less utilization of flexible ureteroscope and decreased deflection time in tURSL could potentially reduce the medical cost.

Comparison of ESWL and ureteroscopic holmium laser lithotripsy in management of ureteral stones

Background

There are many options for urologists to treat ureteral stones that range from 8 mm to 15 mm, including ESWL and ureteroscopic holmium laser lithotripsy. While both ESWL and ureteroscopy are effective and minimally invasive procedures, there is still controversy over which one is more suitable for ureteral stones.

Objective

To perform a retrospective study to compare the efficiency, safety and complications using ESWL vs. ureteroscopic holmium laser lithotripsy in management of ureteral stones.

Methods

Between October 2010 and October 2012, 160 patients who underwent ESWL or ureteroscopic holmium laser lithotripsy at Suzhou municipal hospital for a single radiopaque ureteral stone (the size 8–15 mm) were evaluated. All patients were followed up with ultrasonography for six months. Stone clearance rate, costs and complications were compared.

Results

Similarity in stone clearance rate and treatment time between the two procedures; overall procedural time, analgesia requirement and total cost were significantly different. Renal colic and gross hematuria were more frequent with ESWL while voiding symptoms were more frequent with ureteroscopy. Both procedures used for ureteral stones ranging from 8 to 15 mm were safe and minimally invasive.

Conclusion

ESWL remains first line therapy for proximal ureteral stones while ureteroscopic holmium laser lithotripsy costs more. To determining which one is preferable depends on not only stone characteristics but also patient acceptance and cost-effectiveness ratio.

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.

Improving flexible ureterorenoscope durability up to 100 procedures

BACKGROUND AND PURPOSE

Controversy exists in the literature regarding flexible ureterorenoscopy (F-URS) durability, with a variable expected number of uses from a new F-URS. In this study, a tertiary center experience with the use of two consecutive F-URS is reported and suggestions as to how to improve durability further are made.

MATERIALS AND METHODS

All F-URS performed in the same tertiary care center between July 2009 and February 2011, with two new instruments Flex-X, were reviewed retrospectively. All renal pathology were included. Ureteral cases were excluded. A 9.5F semirigid ureteroscope was always used at the start for a ureteral optical predilation and to explore the upper urinary tract for possible lithotripsy/laser ablation/biopsy. The F-URS was introduced sequentially to explore the remaining calices. Data pertaining to the procedure were collected. The method of sterilization was complete immersion with Cidex®.

RESULTS

The instruments were substituted after 113 and 102 procedures, respectively. The first F-URS was used for a total operative time of 79 hours and 10 minutes while the second one was used for 71 hours and 25 minutes (mean 75 hours and 15 min). Procedure duration was 15 to 175 minutes (mean 58 min). The flexible instruments were used for a mean of 42 minutes per procedure (range 13-153 min). The indications for F-URS were therapeutic in 75.4% and diagnostic in 22.8% of the cases. For lower pole calculi, the stone was relocated in 65.2% and managed with the nonflexed flexible instrument 90% of the time. The most common causes of damage of F-URS were: Deflection mechanism impairment, inner sheath damage, and fiberoptic bundle breaks.

CONCLUSIONS

Increased durability of F-URS was from a variety of factors, a key element of which was the method of sterilization, while routine use of the semirigid instrument initially further contributed significantly to increase the number of F-URS procedures, saving overall costs.

Endoscopic holmium laser treatment for ureterolithiasis

INTRODUCTION

The rapid development and invention of ever more technologically advanced ureterorenoscopes as well as other instruments used in fragmenting ureteral stones have made the traditional surgical treatment of ureterolithiasis very rare.

MATERIAL AND METHODS

We investigated 727 patients treated for ureterolithiasis. 769 ureteroscopic lithotripsies (URSL) with the holmium laser were performed. We evaluated the relation of the stone size, the section of the ureter involved, length of time of the stone within the ureter and the condition of the urinary tract to the results of the ureterolithiasis treatment.

RESULTS

A good result of breaking up the stone and passing its fragments out of the ureter within 3 months following the first URSL was observed in 642 (90.9%) out of 706 patients. The remaining 64 (9.1%) patients required additional procedures: ESWL was performed on 44 patients; URSL was repeated for 20 patients. The most serious early post-URSL complications involved: urinary tract infection with symptoms of urosepsis in 10 patients, leading to death in 1 case, ureteral perforation in 3 patients, including 1 case presenting a periureteral leak that necessitated a surgical intervention.

CONCLUSIONS

URSL with the holmium laser is an effective and safe method for treating ureterolithiasis.

Contemporary management of ureteral stones

CONTEXT

Ureteral calculi represent a common condition that urologists encounter in everyday practice. Several treatment options are available for calculi that do not pass spontaneously or are unlikely to do so.

OBJECTIVE

In this nonsystematic review, we summarize the existing data on contemporary management of ureteral stones focusing on medical expulsive therapy (MET) and different treatment modalities.

EVIDENCE ACQUISITION

A PubMed search was performed. We reviewed the recent literature on the management of ureteral calculi. Articles were considered between 1997 and 2011. Older studies were included selectively if historically relevant.

EVIDENCE SYNTHESIS

For stones that do not pass spontaneously or with MET, shock wave lithotripsy (SWL) and ureteroscopy (URS) are the most common and efficient treatment modalities. Both techniques have obvious advantages and disadvantages as well as different patterns of complications. For select cases or patients, other modalities may be useful.

CONCLUSIONS

Ureteral stones of up to 10mm and eligible for observation may be offered MET. For most ureteral calculi that require treatment, advances in SWL and URS allow urologists to take a minimally invasive approach. Other more invasive treatments are reserved for select "nonstandard" cases.

Ureteroscopic retrograde intrarenal surgery after previous open renal stone surgery: initial experience

The management of renal calculi following previous open surgery represents a challenge for urologists. The aim of this study is to evaluate the outcomes and safety of ureteroscopic laser retrograde intrarenal surgery (RIRS) for renal calculi following prior open renal surgery. The charts of 53 patients who underwent RIRS for renal calculi following prior open surgery for urolithiasis were reviewed. Both flexible and semi-rigid ureteroscopes were utilized together with holmium: YAG laser for stone disintegration. Intravenous urography, computed tomography (CT) and ultrasound were used to evaluate the patient, perioperatively. Stone size ranged from 5 to 32 mm (mean 14.3 mm). The mean operative time was 86 min (20-130). The overall stone-free rate was 92.4%. The overall stone-free rates after one and two-procedures were 79.2% (42 cases) and 92.4% (49 cases), respectively. Four patients (7.5%) had larger residual fragments, 2 (3.8%) of them underwent SWL, and 2 (3.8%) cases were followed up conservatively. Major complications were reported in two patients (3.8%). Stone analysis revealed calcium oxalate in 39 patients, uric acid in 5, calcium phosphate in 4, struvite in 3, and cystine in 2 cases. Ureteroscopic retrograde intrarenal surgery for renal calculi following prior open renal surgery was a minimally invasive, safe procedure with a high success rate. It is a viable alternative for PNL in managing recurrent renal calculi efficiently.

Retrograde intrarenal surgery for lower pole renal calculi smaller than one centimeter

Objectives:

Recently there has been an increasing interest in the application of retrograde intrarenal surgery (RIRS) for managing renal calculi. In this review we discuss its application for the management of lower calyceal (LC) stones less than 10 mm in maximum dimension.

Materials and Methods:

Literature was reviewed to summarize the technical development in flexible ureterorenoscopy and its accessories. Further, the indications, outcome and limitations of RIRS for LC calculi < 1 cm were reviewed.

Results:

Use of access sheath and displacement of LC stone to a more favorable location is increasingly employed during RIRS. Patients who are anticoagulated or obese; those with adverse stone composition and those with concomitant ureteral calculi are ideally suited for RIRS. It is used as a salvage therapy for shock wave lithotripsy (SWL) refractory calculi but with a lower success rate (46-62%). It is also increasingly being used as a primary modality for treating LC calculi, with a stone-free rate ranging from 50-90.9%. However, the criteria for defining stone-free status are not uniform in the literature. The impact of intrarenal anatomy on stone-free rates after RIRS is unclear; however, unfavorable lower calyceal anatomy may hamper the efficacy of the procedure. The durability of flexible ureteroscopes remains an important issue.

Conclusions:

RIRS continues to undergo significant advancements and is emerging as a first-line procedure for challenging stone cases. The treatment of choice for LC calculi < 1 cm depends on patient's preference and the individual surgeon's preference and level of expertise.

Fluid-electrolyte and renal pelvic pressure changes during ureteroscopic lithotripsy

Abstract The objective of the study was to evaluate fluid-electrolyte and renal pelvic pressure (RPP) changes during ureteroscopic lithotripsy. Fifteen patients were detected with residual ureteral calculi after minimally invasive percutaneous nephrolithotomy (MPCNL), distal ureter calculi in three, midureter calculi in four, proximal calculi in eight. RPP was measured via the percutaneous nephrostomy tube by urodynamic study at irrigation pressures of 50, 100 and 200 mmHg. Haemoglobin (Hb), haematocrit (Hct), blood urea mitrogen (BUN), creatinine (Cre), serum sodium (Na(+)), potassium (K(+)), chlorine (Cl(-)) were recorded before and after ureteroscopic lithotripsy. There were no significant differences between Hb, Hct, BUN, Cre, Na(+), K(+), Cl(-) values. Baseline RPP was (16.37 ± 3.14) cmH(2)O, RPPs were 46.06 ± 6.85 cmH(2)O, 99.07 ± 14.62 cmH(2)O and 166.27 ± 33.08 cmH(2)O at irrigation pressures of 50, 100 and 200 mmHg, they were much higher than baseline RPP (p < 0.0001). RPP in the proximal ureter was much higher than in the distal and middle ureter, 50.98 ± 4.52 cmH(2)O versus 40.44 ± 4.07 cmH(2)O (p = 0.0004), 110.26 ± 2.39 cmH(2)O versus 86.29 ± 11.60 cmH(2)O (p = 0.0014), 193.21 ± 5.88 cmH(2)O versus 135.47 ± 20.95 cmH(2)O (p = 0.0002) at irrigation pressures of 50, 100 and 200 mmHg. There were no significant changes in fluid-electrolyte. RPP was significantly increased during ureteroscopic lithotripsy, it was correlated with the irrigation pressure and the position in the ureter.

Ureterorenoscopic treatment of ureteral stones--influence of operator's experience and skill on the procedure outcome

Aim

To observe the influence of operating urologist’s education and adopted skills on the outcome of ureterorenoscopy treatment of ureteral stones.

Methods

The study included 422 patients (234 men, 55.4%) who underwent ureterorenoscopy to treat ureteral stones at the Urology Department of Clinical Hospital Center Split, Croatia, between 2001 and 2009. All interventions were carried out with a semi-rigid Wolf ureteroscope and an electropneumatic generator used for lithotripsy. The operating specialists were divided into two groups. The first group included 4 urologists who had started learning and performing endoscopic procedures at the beginning of their specialization and the second group included 4 urologists who had started performing endoscopic procedures later in their careers, on average more than 5 years after specialization.

Results

Radiology tests confirmed that 87% (208/238) of stones were completely removed from the distal ureter, 54% (66/123) from the middle ureter, and 46% (28/61) from the proximal ureter. The first group of urologists completed significantly more procedures successfully, especially for the stones in the distal (95% vs 74%; P = 0.001) and middle ureter (66% vs 38%; P = 0.002), and their patients spent less time in the hospital postoperatively.

Conclusion

Urologists who started learning and performing endoscopic procedures at the beginning of their specialization are more successful in performing ureteroscopy. It is important that young specialists receive timely and systematic education and cooperate with more experienced colleagues.

Flexible ureterorenoscopy and holmium laser lithotripsy for the management of renal stone burdens that measure 2 to 3 cm: a multi-institutional experience

BACKGROUND AND PURPOSE

Percutaneous nephrostolithotomy (PCNL) is the current standard of care for management of large renal stones (>2 cm). Recent studies have evaluated flexible ureterorenoscopy (URS)/holmium laser lithotripsy as an alternative treatment for patients with contraindications to or preference against PCNL. Stones in an intermediate size range (2-3 cm) may be most amenable to URS/laser lithotripsy as definitive treatment in a single stage. We report a multi-institutional series of URS/laser lithotripsy for renal stone burdens that measure 2 to 3 cm.

PATIENTS AND METHODS

Patients who underwent URS/holmium laser lithotripsy for renal stones that measured 2 to 3 cm were identified retrospectively at three tertiary care centers. Demographic information, disease characteristics, and perioperative and postoperative data were gathered. Patients with renal stone burdens of 2 to 3 cm who were treated by URS/laser lithotripsy and had at least one postoperative visit and imaging study were included. Stone clearance was evaluated using 0-2 mm and <4 mm residual stone burden on postoperative imaging.

RESULTS

One hundred and twenty patients underwent URS/holmium laser lithotripsy for renal stones of 2 to 3 cm. Mean stone burden was 2.4 cm, and mean body mass index was 29.3 kg/m². Indications for URS/laser lithotripsy vs PCNL included patient preference (57), technical or anatomic factors (24), patient comorbidities (17), failed shockwave lithotripsy (9), patient body habitus (3), solitary kidney (3), chronic renal insufficiency (3), and strict anticoagulation (2). Thirty-one (26%) patients had stent placement preprocedure, and 94 (78%) patients underwent outpatient surgery. A ureteral access sheath was used in 67%. One hundred and one (84%) patients underwent single-stage procedures. There was one intraoperative complication (ureteral perforation), and there were eight minor postoperative complications (6.7%). The reoperation rate through the mean 18-month follow-up was 3/120 or 2.5%. Seventy-six (63%) patients had residual stone burden of 0 to 2 mm, and 100 (83%) patients had residual burden of <4 mm.

CONCLUSIONS

We demonstrate that single-stage URS/holmium laser lithotripsy is effective for management of renal stones that measure 2 to 3 cm through intermediate follow-up. Staged procedures can be used selectively for technical reasons or disease factors. Although PCNL achieves superior stone clearance overall, URS/laser lithotripsy is a viable treatment option for selected patients.

[Retrograde intrarenal surgery (RIRS). Technical complement for cases of acute lithiasis]

INTRODUCTION

Washing the renal cavities using minipercutaneous surgery shaft is an ideal technical procedure for retrograde intrarenal surgery (RIRS) when lithiasic fragmentation is significant or if the anatomy of the renal cavities may obstruct the spontaneous elimination of fragments.

MATERIALS AND METHODS

we performed 37 RIRS on 35 patients with renal lithiasis (14 men, 21 women) with a mean age of 56 (range 33-72) years, divided into two groups in accordance with the size of their kidney stones. Group A, 23 patients with lithiasis <1.5 cm; Group B, 12 cases with lithiasis >1.5 cm. 28 patients had a single kidney stone and 7 had multiple stones.

APPROACH

Flexible uretrorenoscopy, 7.5 Fr (Flex-X(®, Karl Storz) by means of a ureteral access sheath. Holmium laser lithotripsy (Calculase®, Karl Storz) using 200 and 365 micrometer fibres. Fragment extraction with 1.7 Fr nitinol baskets (N-gage, Cook). In cases of significant fragmented stone burden, the renal cavities were washed with low-pressure fluid irrigation using a ureteral access sheath, which was collected together with the stone fragments carried by the "mini-perc" sheath (Ultrax-x® 18Fr, Cook; Rusch, 14 Fr) placed under radiologic and endoscopic control at the level of the calyx-papilla selected for fragment drainage.

RESULTS

the mean diameter for group A was 9.13 (range 5-13) mm and 20.25 (range 16-28) mm for group B. The overall mean operating time was 81 (range 30-160) min. Group A required 66.43±35.18 min. and group B 107.5±46.73 min. (p=0.006). The rate of absence of stones immediately after surgery was 83.2%, 93.1% at 3 months (95.6% for A and 83.3% for B; p=0.217). In no case was ureteral stenosis observed as a result of the use of ureteral access sheaths. In 7 group B patients (58.3%) with acute lithiasis and/or alteration in their pyelocaliceal anatomy, we performed active lavage of the renal cavities applying the aforementioned percutaneous technique. The mean post-surgery hospital stay was 2.1 (range 1-4) days. There were post-surgery complications (Clavien 1) in 7 patients (20%). Two patients required a second FURS.

CONCLUSIONS

RIRS can be effective treatment for renal lithiasis >1.5 cm. Lavage of the renal cavities helps to eliminate stone fragments, reducing the possibility of retreatment.

Is a safety wire necessary during routine flexible ureteroscopy?

BACKGROUND AND PURPOSE

The use of flexible ureteroscopy (URS) for nephrolithiasis has been rapidly expanding. Initially, safety guidewires were maintained alongside the ureteroscope during stone manipulation to prevent loss of access and allow stent insertion in the event of perforation. We intend to determine the safety of flexible URS without a separate safety guidewire in a large series of patients.

METHODS

A retrospective chart review was performed on all cases of flexible URS with laser lithotripsy performed by a single surgeon from August 2003 to May 2008. Preoperative patient characteristics, radiographic stone sizes, operative findings, and postoperative outcomes were recorded. Patients with renal or ureteropelvic junction (UPJ) stones were isolated for a qualitative data analysis.

RESULTS

Flexible URS was performed on 305 kidneys in 246 consecutive patients, of which 59 cases were bilateral. Cases were subdivided into complicated and uncomplicated. Two hundred seventy cases were uncomplicated and performed without a safety guidewire. No intraoperative complications resulted from the lack of a safety guidewire, including no cases of lost access, ureteral perforation/avulsion, or need for percutaneous nephrostomy tube. Thirty-five cases were complicated, necessitating a safety guidewire. Of these, 16 had concomitant obstructing ureteral stones, 5 had encrusted ureteral stents, and 14 had difficult access because of large stone burden or aberrant anatomy.

CONCLUSIONS

This study demonstrates that, in a large series of patients, a safety guidewire was not necessary for routine cases of flexible URS with laser lithotripsy on renal or UPJ stones. Particular cases with complicated anatomy, difficult access, concomitant ureteral stones, simultaneous stone basketing, or bulky stone burden still necessitate use of a safety guidewire because of increased risk of adverse outcomes.

Use of NTrap® during Ureteroscopic Lithotripsy for Upper Ureteral Stones

Purpose

This study aimed to determine the value of the NTrap® (Cook Urological INC, USA), which was designed to block the upward movement of stones during ureteroscopic lithotripsy.

Materials and Methods

We reviewed the data of 144 patients who underwent ureteroscopic lithotripsy for an upper ureteral stone from June 2006 to May 2010. Sixty-eight patients who underwent ureteroscopic lithotripsy without the use of the NTrap® were assigned to Group I and 76 patients who underwent ureteroscopic lithotripsy with the NTrap® were assigned to Group II. The size of the stones, operation time, success rate, and pre- and postoperative complications were compared retrospectively between the two groups.

Results

The mean age of the patients (Group I: 35.8 years; Group II: 32.6 years) and the sex ratios were not significantly different between the two groups. The mean size of the stones was 6.9 mm and 7.4 mm, which also was not significantly different between the two groups. The mean operation time was 82.7 minutes and 78.7 minutes. The operation time was shorter in Group II, but the difference was not significant. The success rate of stone removal was 89.7% and 98.7% in Groups I and II, respectively; Group II showed a significantly higher success rate. Two cases of ureteral perforation and one case of ureteral avulsion occurred in Group I, and one case of ureteral perforation occurred in Group II.

Conclusions

NTrap®, which is an instrument used to assist during ureteroscopic lithotripsy, can be considered to be an effective tool that blocks the upward movement of the stone and aids in safe stone removal.

A Review of Studies Reporting on Complications of Upper Urinary Tract Stone Ablation Using the Holmium:YAG Laser

Purpose:

A review of the literature of studies reporting complications of ureteroscopic urinary tract stone ablation using the holmium:YAG laser was performed.

Patients and methods:

Electronic databases were searched using specific keywords to identify relevant studies. Reference lists of identified articles were scrutinised for other studies and searches were conducted using the names of authors known to have published widely in this field. Two reviewers assessed retrieved articles for inclusion criteria. Patients <16 years old were excluded.

Results:

Overall, 48 studies published between 1994 and 2007 were included. Half were published since 2000. In total, 4454 patients were identified. Around half of studies were performed in North America (25). The number of patients per study varied from 8 to 598. The study populations were very heterogeneous in terms of stone position and size, and ureteroscope size and rigidity. Overall, 303 (6.8%) complications were identified. Post-operative ureteric stricture and perforation rates were both 1.0%. There were only six major complications identified (0.1%). The post-operative sepsis rate was 2% and one death was reported.

Conclusions:

Upper urinary tract stone ablation using the holmium:YAG laser is both safe and reliable. Follow-up imaging to detect procedure-specific complications would not appear to be routinely indicated given this low complication rate.

Treatment of large proximal ureteral stones: extra corporeal shock wave lithotripsy versus semi-rigid ureteroscope with lithoclast

Purpose

Assessment of safety and efficacy of extracorporeal shockwave lithotripsy versus semi-rigid ureteroscope with lithoclast for treatment of large proximal ureteral stones.

Materials and methods

The study included 147 patients with large upper ureteral stones. SWL and ureteroscopy were performed in 71 and 76 patients respectively. Patients in the SWL group were treated with Siemens: - Modularis lithovario under intravenous sedation on an out patient basis. Patients in the ureteroscopy group were treated with (7.5 Fr) semi-rigid ureteroscope and lithoclast under spinal anesthesia on a day care basis.

Results

Stone - free rate for in situ SWL was 58% (41 of 71) patients. For semi-rigid ureteroscope accessibility of the stones was 94% (72 of 76) and the stone free rate was 92% (70 of 76) No major complications were encountered in both groups.

Mean stone size was 1.34 ± 0.03 cm in the SWL group and 1.51 ± 0.04 in the ureteroscopy group.

Conclusions

Our study demonstrates that ureteroscopy with lithoclast can be considered as acceptable treatment modality for large proximal ureteral calculi and can be considered as fist line for treatment of large proximal ureteral stones.

[Diagnostic and therapeutic ureteroscopy: is dilatation of ureteral meatus always necessary?]

OBJECTIVE

To assess the feasibility and safety of diagnostic or therapeutic semirigid ureteroscopy without ureteral meatus dilatation.

MATERIALS AND METHODS

A comparative, retrospective study was conducted of patients undergoing ureteroscopy from January 2000 to May 2008. For data analysis purposes, the population was divided into two groups based on whether ureteroscopy had been performed with (Group 1) or without (Group 2) ureteral meatus dilatation. Variables recorded included age, sex, type of procedure, surgical diagnosis, passive or active dilatation, number of stones, stone location, stone diameter, peroperative and postoperative complications, internal urinary diversion after the procedure, therapeutic success rate, operating time, and hospital stay duration. A 8-9.8 Fr Wolf semirigid ureteroscope was used. Descriptive statistics of the population and cohorts were performed, providing medians, quartiles, and limit values for non-normally distributed interval variables, and absolute and relative frequencies for categorical variables. Shapiro-Wilk's, Mann-Whitney's U, Chi-square, and Fisher's exact tests were used for statistical analysis. A value of p 2 alpha < or = 0.005 was considered statistically significant. Arcus Quickstat Biomedical 1.0 software was used.

RESULTS

Among the 306 ureteroscopies studied, 286 performed in 256 patients were analyzed. Median age was 50 years (16-83), 59% of patients were male, and elective ureteroscopy was performed in 183 patients (64%). Group 1: 191 ureteroscopies, Group 2: 95 ureteroscopies. Stone location: 149 in distal ureter, 60 in middle ureter, and 35 in proximal ureter. Sixty-nine percent of stones had sizes ranging from 5 and 10 mm. The overall success rate was 86.5%. There were 5 peroperative and 22 postoperative complications, with no statistically significant differences between the groups.

CONCLUSIONS

In selected cases, ureteroscopy may be performed without ureteral meatus dilatation with success and morbidity rates similar to when the procedure is performed with meatal dilatation.

A prospective randomized study comparing shock wave lithotripsy and semirigid ureteroscopy for the management of proximal ureteral calculi

OBJECTIVES

To conduct a prospective randomized study comparing both techniques for the management of solitary radio-opaque upper ureteral stones < 2 cm in diameter. The ideal treatment for upper ureteral stones > 1 cm size remains to be determined with shock wave lithotripsy (SWL) and ureteroscopy (URS) being acceptable options.

METHODS

A total of 200 patients were included in the study. They were randomized into 2 equal groups. Group A underwent in situ SWL as a primary therapy. Group B underwent URS, using semirigid URS with intracorporeal lithotripsy. Efficiency quotient (EQ), cost analysis, and predictors of failure were estimated for both techniques.

RESULTS

For stones of size > or = 1 cm, the initial stone-free rate for URS and SWL was 88% and 60%, respectively. The estimated EQ was 0.79 and 0.43 for both techniques respectively. For stones < 1 cm, the initial stone-free rate for URS and SWL was 100% and 80%, respectively. The estimated EQ was 0.88 and 0.70 for both techniques, respectively. The mean cumulative costs were significantly more in SWL group (P <.05). Predictors of URS failure included; male gender, failure to pass guidewire beyond the stone, and extravasation. Predictors of SWL failure included large stone size > 1 cm, calcium oxalate monohydrate stone, and higher degrees of hydronephrosis.

CONCLUSIONS

URS with intracorporeal lithotripsy is an acceptable treatment modality for all proximal ureteral calculi, particularly stones > 1 cm. SWL should remain the first-line therapy for proximal ureteral calculi < or = 1 cm because of the less invasive nature and lower anesthesia (i.v. sedation).

Secondary signs of non-enhanced CT prior to laser ureterolithotripsy: is treatment outcome predictable?

PURPOSE

To correlate the presence of secondary signs of non-enhanced computed tomography (NECT) in renal units harboring ureteral calculi with intraoperative findings and treatment outcome after holmium:yttrium-aluminum-garnet laser (Ho:YAG) ureterolithotripsy.

SUBJECTS AND METHODS

Two-hundred patients were prospectively included after ureteral calculi were detected on NECT. All patients underwent Ho:YAG ureterolithotripsy at the Medical University of Vienna. All CT studies were reviewed by one specialized uroradiologist blinded to pre- and postoperative parameters for secondary signs as renal enlargement, perinephric stranding, ureteral dilation, periureteral edema, and ureteral rim sign. The impact of secondary signs on intraoperatively-verified impaction and treatment outcome was evaluated.

RESULTS

Of the 200 patients 85 (42.5%) harbored proximal and 115 (57.5%) harbored distal ureteral calculi. The stone-free rates for proximal and distal calculi were 80% and 97%, respectively. Although proximal stone location and intraoperatively-verified impaction correlated significantly with stone-free rates (P < 0.0001, P = 0.01), the presence of secondary signs could not predict intraoperatively-verified stone impaction or stone-free rates (renal enlargement: P = 0.2, P = 0.5; perinephric stranding: P = 0.7, P = 0.5; ureteral dilation: P = 0.7, P = 0.7; periureteral edema: P = 0.8, P = 0.06; ureteral rim sign: P = 0.8, P = 0.3).

CONCLUSION

Preoperative secondary signs seen on NECT in patients harboring ureteral calculi do not correlate with intraoperative findings of impaction, and do not predict treatment outcome after Ho:YAG ureterolithotripsy.

Efficacy of intravesical ropivacaine injection on urinary symptoms following ureteral stenting: a randomized, controlled study

PURPOSE

Previous studies suggest that intravesical administration of nonsteroidal anti-inflammatory drugs may reduce the troublesome voiding symptoms and pain related to ureteral stenting. The objective of this study was to investigate the effectiveness of a long-acting local anesthetic, ropivacaine, injected submucosally into the bladder to control ureteral stent-associated symptoms.

MATERIALS AND METHODS

A randomized, single-blinded, study approved by our Institutional Review Board of adult patients scheduled for ureteroscopic stone surgery and possible stent placement was conducted. Patients were randomized to either the treatment cohort, who received five injections of 2 mL 0.5% ropivacaine around the ureteral orifice or to the control cohort, who received five injections of 2 mL of 0.9% normal saline in identical locations. Pain scale questionnaires were provided to each subject preoperatively and at postoperative hours 2, 4, 8, 24, and 48 as well as on the day of stent removal. Student's t test and Wilcoxon signed rank sum tests were used for Gaussian and nonparametric data, respectively.

RESULTS

Twenty-two patients were randomized evenly into the two cohorts. The ropivacaine group consisted of 11 patients (eight men and three women) with a mean age of 56.2 years (standard deviation [SD] = 12, range 27-69), and the saline group consisted of eleven patients (six men and five women) with a mean age of 47.8 years (SD = 6.6, range 37-58). Intraoperative parameters appeared similar between the two cohorts. Intraoperative and postoperative narcotic usage was not different between the two groups, except at postoperative hour 2 when it favored the ropivacaine cohort (P = 0.05). Trends favoring ropivacaine in flank pain, bladder pain, genitalia pain, and hematuria domains were seen as long as 8 hours and up to the day of stent removal. Trends of less magnitude and duration were seen in the dysuria domain. No differences were seen in the frequency and urgency domains.

CONCLUSIONS

Our preliminary investigation with intravesical injection of ropivacaine before ureteroscopic surgery demonstrated trends toward decreased pain and voiding symptoms in this small-sample study. Inclusion of a larger sample should definitively address the effectiveness of intravesical ropivacaine and its impact on stent-related symptoms.

Nonstented versus routine stented ureteroscopic holmium laser lithotripsy: a prospective randomized trial

We conducted a prospective, randomized study to evaluate whether postoperative ureteral stenting is necessary after ureteroscopic holmium laser lithotripsy. A total of 115 consecutive patients with distal or middle ureteral calculi amenable to ureteroscopic holmium laser lithotripsy were prospectively randomized into stented group (n = 58) and nonstented group (n = 57). The stent was routinely placed in the treated ureter for 2 weeks. The outcomes were measured with postoperative patient symptoms, stone-free rates, early and late postoperative complications, and cost-effectiveness. The postoperative symptoms were measured with Ureteral Stent Symptom Questionnaire (USSQ). All patients completed a 12-week follow-up. There was no significant difference between two groups with respect to the patient age, stone size, stone location and mean operative time. According to the USSQ, the symptoms of the stented group were significantly worse compared to the nonstented group (P = 0.0001). In the stented group, two patients had high fever for 1 week after the operation, stent migration was found in two patients, and the stents had to be removed earlier in five patients because of severe pain or hematuria. The cost of the stented group was significantly higher than the nonstented group. The stone-free rate was 100% in both groups. No hydronephrosis or ureteral stricture was detected by intravenous pyelogram in the 12th week postoperative follow-up. In conclusion, we believe that routine stenting after ureteroscopic intracorporeal lithotripsy with the holmium laser is not necessary as long as the procedure is uncomplicated for distal or middle ureteral calculis less than 2 cm.

How efficient is extracorporeal shockwave lithotripsy with modern lithotripters for removal of ureteral stones?

PURPOSE

To analyze results of extracorporeal shockwave lithotripsy (SWL) for treatment of ureteral stones with two modern lithotripters.

PATIENTS AND METHODS

A consecutive series of 598 patients with ureteral stones was treated with the Modulith SLX Classic and Modulith SLX-F2 lithotripters. The mean (SD) age of the patients was 54 (17) years, and the mean (SD) stone surface area was 42 (34) mm2. Results were available for 580 patients.

RESULTS

Stone-free ureters were recorded in 563 (97.1%) patients. Stone-free rates were 96.1%, 97.8%, and 97.9%, for the proximal, middle, and distal ureter, respectively. The average number of SWL sessions needed was 1.31. For the proximal, middle, and distal ureter, one SWL session was sufficient in 73.1%, 66.7%, and 83.2% of patients, respectively. Assisting auxiliary procedures were used in 102 patients (18%). The total mean (SD) treatment time was 48 (26) minutes and the mean (SD) number of shockwaves was 3266 (2258). SWL for stones located in the proximal, middle, and distal ureter was carried out in the prone position in 38%, 88%, and 9%, respectively. For 90 patients primarily treated with a large focus, the re-treatment rate was the same as for patients treated with a standard focus. A stone treatment index used to assess the efforts, results, and complications was similar for the two lithotripters and for all stone locations. Thus both lithotripters had similar efficacy.

CONCLUSION

With consistent use of SWL, a stone-free rate of more than 97% can be attained, with a reasonable re-treatment rate and only modest use of assisting auxiliary procedures.

FlexGuard: a new laser insertion sheath: functional aspects in ureterorenoscopy (URS)

The evolution of flexible ureteroscopes led to a widespread use for the management of upper urinary tract abnormalities. The cost of purchase, maintenance and the durability of these instruments has become a major issue. This work describes a new device to avoid damages due to incorrect use of the Holmium laser during insertion of the laser fibre. A laser fibre with an optical core of 271 and 430 muicrom outside diameter was slid inside the FlexGuard laser fibre insertion sheath (LISA laser products, Germany). The outside diameter of the sheath measures 2.7 F (0.9 mm) and 2.1 F (0.7 mm) luminal diameter. The distal fibre tip was brought up to a position app. 2 mm inside the distal end of the sheath. The loaded sheath was pushed through the working channel of various ureteroscopes which were in maximum deflection. With the insertion sheath protruding about 2 mm from the distal tip of the URS the fibre was effortless forwarded out of the sheath to approach the stone. Once the laser fibre was in position, the sheath was removed, to increase the volume of irrigation fluid during laser lithotripsy. The radius of curvature (ROC) of the URS in maximum deflection and the integrity of the working channel was investigated. Using the insertion sheath the laser fibre reached the working position without any recognition of scratching or resistance. The integrity of the ureterorenoscopes was checked thoroughly be manually operated manometry. No damage of the inner surface of the working channel occurred. The ROC of the instrument did not change significantly during this procedure. After removal of the sheath the ROC remained stable. With the extended use of ureteroscopy, durability and repair costs are of concern. Damage resulting from incorrect use of laser fibres is a major issue in this respect. FlexGuard proved to avoid this damage in all flexible ureteroscopes investigated without limiting their mobility.

Holmium laser for stone management

The efficiency and safety profile of the holmium laser has made this tool a versatile multi-purpose instrument for use in the endoscopic treatment of a wide variety of urologic disorders, in particular urinary calculi. Herein we review holmium laser physics, current endourologic laser lithotripsy applications, and the performance of new low power holmium laser devices.

Emergency ureteroscopic management of ureteral stones: why not?

OBJECTIVES

To describe a single-center experience in the emergency ureteroscopic management of ureteral stones.

METHODS

We retrospectively considered the data from 144 patients (mean age 49.6 years, range 23 to 82) who had had obstructive ureteral stones and had undergone emergency ureteroscopy with stone retrieval. Intracorporeal pneumatic lithotripsy was performed when necessary. At the end of the procedure, a ureteral catheter was systematically left in place in 100 patients (69.4%) and removed within 24 hours. In the remaining 44 patients, a double-J stent was preferred and was removed within 30 days, depending on the clinical course. Stone-free status was defined as the complete absence of fragments at 1 month of follow-up.

RESULTS

The calculi were more frequently localized in the distal ureter than in the proximal one (90.3% versus 9.7%, respectively). The overall mean stone diameter was 9.1 mm (range 5 to 20). The overall stone-free rate was 92.4%. A greater stone-free rate was obtained in those with stones less than 10 mm (95.8%) than in those with stones larger than 10 mm (89%, P = 0.002). Similarly, a significantly better outcome occurred for those with stones located in the distal ureter (94.6%) than for those with stones in the proximal one (71.4%, P = 0.004). The overall complication rate was 4.2%. The mean hospital stay was 2.5 days (range 1 to 7).

CONCLUSIONS

In our experience, emergency ureteroscopy in cases of obstructive ureteral stones proved to be safe and effective. It has the main advantage of offering both immediate relief from pain and stone fragmentation. Additional extensive studies are warranted to corroborate these findings.