Cost-Effectiveness of Anti-Retropulsion Devices for Ureteroscopic Lithotripsy

The reverse Trendelenburg position in proximal ureteral stone management: A systematic review and meta-analysis

INTRODUCTION

Ureteroscopy lithotripsy (URSL) presents a therapeutic option for patients with proximal ureteral calculi warranting active removal. This systematic review and meta-analysis aimed to assess the efficacy of the reverse Trendelenburg (RT) position during this procedure.

MATERIALS

A comprehensive literature search was conducted across PubMed, Embase, and Cochrane databases to identify randomized controlled trials and observational studies comparing RT versus standard positioning (STD) in patients undergoing URSL for proximal ureteral stones. Heterogeneity was measured with the Cochran's Q test, I2 statistics, and prediction intervals (PI). A DerSimonian and Laird random-effects model was utilized for all outcomes.

RESULTS

Four studies encompassing 505 patients undergoing URSL were analyzed. Among the studied participants, 293 (58%) underwent RT positioning. Overall, RT was associated with a lower average incidence of stone retropulsion (RR 0.42; 95% CI 0.27-0.65; I2=48%; PI 0.08-2.10) and a higher mean stone-free rate (RR 1.33; 95% CI 1.18-1.49; I2=0%). However, no significant difference between groups was found in the mean rate of overall complications (RR 0.76; 95% CI 0.40-1.43; I2=51%; PI 0.00-520.22) and operative time (MD -0.65; 95% CI -9.58-8.27; I2=94%; PI -111.95-110.65). In those with proximal ureteral stones undergoing RT positioning at only the 20° angle, there was a reduction in stone retropulsion without any measured heterogeneity (RR 0.35; 95% CI 0.23-0.52; I2=0%).

CONCLUSION

These findings suggest that RT positioning is effective in improving outcomes for patients with proximal ureteral stones undergoing URSL, and its use should be considered during the procedure.

A new position utilizing the effect of gravity in proximal ureteral stones, ureteroscopic lithotripsy in the reverse Trendelenburg position: a prospective, randomized, comparative study

PURPOSE

To evaluate the effect of the reverse Trendelenburg position in patients undergoing ureteroscopic lithotripsy for proximal ureteral stones.

METHODS

The study included 167 patients who underwent ureteroscopic lithotripsy for proximal ureter stones between December 2020 and September 2022. The patients were randomly assigned to one of three groups: standard lithotomy (n:55), 10° reverse Trendelenburg (n:55), and 20° reverse Trendelenburg (n:57). Preoperative information, including age, sex, body mass index (BMI), previous shock wave lithotripsy (SWL), stone side, volume, and density, distance to the ureteropelvic junction (UPJ) of the stone, and hydronephrosis degree. Stone-free status was evaluated with computed tomography (CT) at 4 weeks postoperatively. The groups were compared in respect of stone migration, stone-free rate, use of flexible ureterorenoscope, operating time, postoperative length of stay in the hospital, and complications.

RESULTS

No statistically significant difference was determined between the groups with respect to age, sex, BMI, previous SWL, stone side, volume and density, distance to the UPJ of the stone, and hydronephrosis degree (p > 0.05 for all). Statistically significant differences were determined between the groups with respect to stone migration (p = 0.001), stone-free rate (p < 0.001), use of flexible ureterorenoscope (p = 0.01), operating time (p < 0.001), hospital length of stay (p < 0.001), postoperative fever (p = 0.002), and total complications (p = 0.01).

CONCLUSION

A new patient position is presented in this study, which can be used in ureteroscopic lithotripsy performed for proximal ureteral stones. The reverse Trendelenburg position constitutes a surgical method that can be used safely and successfully in the treatment of proximal ureteral stones.

TRIAL REGISTRATION NUMBER

NCT04894058, 05/21/2021, Prospectively registered.

Reverse Trendelenburg Positioning Minimizes Stone Retropulsion During Ureteroscopic Laser Lithotripsy: A Prospective Randomized Study

Purpose: Retropulsion of stone fragments during ureteroscopic laser lithotripsy (URSLL) remains a challenge for urologists and is associated with increased operative time and reduced stone-free rate (SFR). In this study, we compared the rate of retropulsion of ureteral stones during URSLL between the standard dorsal lithotomy (SDL) position and dorsal lithotomy position with reverse Trendelenburg (RT). Materials and Methods: Patients with ureteral stones requiring surgical intervention between May 2019 and January 2022 were randomized to undergo URSLL in either SDL or RT positions. The primary outcome of this study was stone retropulsion. Secondary outcomes included retropulsion to the kidney, SFR, operative time, 30-day emergency department visits and complications, and the need for conversion from semirigid to flexible ureteroscope. Differences between groups were evaluated using the chi-square test, Fisher exact test, Kruskal-Wallis test, or t-test. Results: A total of 114 patients were included in the study, with 57 patients in each group. There were no differences between groups in terms of baseline demographics or stone characteristics. Retropulsion was significantly less frequent in the RT group (68.4% vs 10.5%, p < 0.01). Similarly, the RT group was favored for lower risk of retropulsion into the kidney (40.4% vs 5.3%, p < 0.01), operative time (43.5 vs 33.0 minutes, p = 0.02), and need for ureteroscope conversion (16.7% vs 2.2%, p = 0.04). There was no difference in the SFR (100% vs 95%, p = 0.49). Conclusions: RT positioning during URSLL for ureteral stones significantly decreases the rate of stone retropulsion, operative time, and the need for conversion from semirigid to flexible ureteroscope.

Endoscopic Management of Upper and Lower Ureteric Stones Using Pneumatic Lithotripter: A Retrospective Medical Records Review

Background

In this study we aimed to assess and compare the rate of sem-irigid ureterorenoscope in the treatment of upper and lower ureter stones through pneumatic lithotripsy (PL).

Materials and Methods

Ninety-two patients with a mean age±SD of 45±15years who had had a surgical procedure performed by the same experienced surgeon between January 2013 and July 2015 were included in the study. The mean±SD stone size was 8.8±2.6 mm. Forty-two of the patients (45.7%) had upper ureter stones and 50 (54.3%) had lower ureter stones in order to increase the success rate and avoid stone migration. The medical files of the patients were reviewed regarding age, sex, stone size, stone location, success rate, complications, and presence of hydronephrosis. Success was operationally defined as the complete fragmentation of stone to very small parts that could pass or complete extraction of the stone.

Results

Eighty-four of the patients were stone free (91%). The success rates for patients with upper or lower ureteric stones were 93% and 90%, respectively (P=0.63). There were no complications during the operation. However, 4 patients (4.4%) had postoperative complications in terms of urinary tract infection or urosepsis. Those were accurately managed by the suitable medical treatment.

Conclusion

Semi-rigid ureterorenoscopy by using PL was a safe and practical treatment option for managing the upper and lower ureter stones. Performing the tips and tricks of ureterorenoscopy by an experienced surgeon seems to enhance the success rate, especially in upper ureter stones.

Impact of forced diuresis on retropulsion of disintegrated ureteral calculi during semi-rigid ureteroscopy: a double-blind randomized-controlled study

The objective of this study is to assess the safety and efficacy of forced diuresis as an antiretropulsion strategy during the pneumatic disintegration of solitary lower ureteric stones with semi-rigid ureteroscopy (URS). A prospective randomized double-blind study was carried out from March 2019 to June 2021 for patients presented with unilateral solitary radiopaque lower ureteric stones ≤ 20 mm. Patients were randomized for URS into two groups, according to the use of forced diuresis using furosemide 1 mg/kg (GII) or not (GI). Perioperative parameters were compared between both groups, including retropulsion rate, stone-free rate (SFR), and need for auxiliary procedures and complications. A total of 148 patients were included; 72 (48.6%) in GI and 76 in the GII (51.4%), with respective stone size of 11.8 ± 2.6 vs.12.1 ± 2.4 mm. Both groups were comparable in demographic and baseline data, with a mean age of 47 ± 16 and 50 ± 14 years for GI and GII, respectively. GII had a significantly shorter disintegration time (10.5 ± 1.3 vs. 4.2 ± 2.1 min, p < 0.001), shorter operative time (33.1 ± 10.1 vs. 40.8 ± 9.1 min, p < 0.001), lower stone fragments migration rate during disintegration (6.5% vs. 18.1%, p = 0.04), lower retropulsion rate (1.3% vs. 11%, p = 0.02), higher SFR (96.1% vs. 86.1%, p = 0.04), and lower auxiliary procedures (3.9% vs. 13.8%, p = 0.03). Intraoperative and 6-h postoperative changes in heart rate and mean systolic blood pressure were comparable between both groups. Ephedrine injection (6–18 mg) was needed in significantly more GII patients (39.5% vs. 20.8%, p ≤ 0.01). It seems that forced diuresis during pneumatic lithotripsy of the lower ureteric stones is a safe and effective antiretropulsion technique. This would expand the alternative options to the antiretropulsion strategy, especially in centers where the laser and flexible ureteroscopes are not available.

Cost-effectiveness of anti-retropulsive devices varies according to the locations of proximal ureteral stones: a retrospective cohort study

Background

Anti-retropulsive devices are often used to prevent stone migration in the treatment of proximal ureteral calculi. They are helpful. However, in the meantime, they also add extra expenses. This study was carried out to investigate the best criteria for treating proximal ureteral stones with anti-retropulsive devices.

Methods

Data from all patients who underwent ureteroscopic holmium: YAG laser lithotripsy for solitary upper ureteral stones in 2018 were collected. Patients who encountered stone retropulsion during the process of inserting the ureteroscope were excluded. Patients were divided into either group URS or group URS + ARD depending on whether the anti-retropulsive device was used. Then, the stone-free rate, expenses and other criteria were compared between groups according to stone location. Stone-free was defined as no stones present.

Results

For stones located ≤ 30 mm from the ureteropelvic junction (UPJ), the stone-free rates for the URS group were 80% and 80% at one day and one month after the operation, respectively. Those for the URS + ARD group were 71.4% and 78.6% at one day and one month, respectively. For stones located 31–90 mm from the UPJ, the stone-free rates were 84.7% and 84.7% for the URS group and 89.6% and 95.5% for the URS + ARD group at one day and one month, respectively. A statistically significant difference occurred at one month. For stones located > 90 mm from the UPJ, the two groups were both stone free. In the URS + ARD group, expenses were higher. In addition, the mean diameter of residual stones derived from stones located at 31–90 mm from the UPJ was statistically smaller, and 4 of 7 residual stones passed spontaneously within one month, which was obviously more than that in other locations and the URS group. Other outcomes, including operation time and postoperative stay, showed no significant difference between the groups.

Conclusion

Anti-retropulsive devices are indeed helpful, but they might be cost-effective for stones located solely in the middle part of the upper ureter, not for those too close to or far from the ureteropelvic junction.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-00995-9.

Laparoscopic ureterolithotomy for large proximal ureteric stones: Surgical technique, outcomes and literature review

INTRODUCTION

We evaluated the efficacy and safety of laparoscopic ureterolithotomy (LPU) for the treatment of large proximal ureteric stone.

METHODS

A retrospective multicenter analysis for patients with solitary impacted proximal ureteric stone ≥15 mm who underwent LPU from 2016 to 2019 was performed. Primary outcome was to estimate the stone-free rate (SFR). SFR was defined as absence of residual stones on postoperative computed tomography scan. Secondary outcome was to assess the perioperative outcomes, as well as to review literature data of randomized controlled trials and meta-analyses comparing LPU to other treatment options.

RESULTS

Forty-four patients were included in our study. Mean stone size was 22.9 ± 5.8 mm and median follow-up was 14 months. Three patients had previous abdominal surgery, one patient had severe degree of scoliosis and six patients failed primary therapy. All stones were extracted successfully (SFR = 100%) without need of auxiliary treatments. Mean operative time and estimated blood loss were 86.6 ± 14.1 minutes. and 11.9 ± 14.7 mL, respectively. No intraoperative complications or conversion to open surgery were reported. No major postoperative complications (≥grade 3) were reported. Mean length of hospital stay was 2 ± 0.8 days.

CONCLUSIONS

For treatment of large ureteric stones, our study showed that LPU achieves 100% stone-free status. When performed by well-trained laparoscopic surgeons, it is safe and has no major perioperative complications. According to our results and literature data, when counseling patients with large impacted proximal ureteral stones, LPU should be advised as the procedure that has the higher SFR, lower auxiliary treatments, and comparable complication rates to other treatments.

"VirtualBasket" ureteroscopic holmium laser lithotripsy: intraoperative and early postoperative outcomes

BACKGROUND

The "VirtualBasket" technology is the result of pulse modulation during holmium laser emission: the laser emits part of the energy to create an initial bubble, and a second pulse is emitted when the vapor bubble is at its maximum expansion, so that it can pass through the previously created vapor channel. The aim of this study is to outline the outcomes of the "VirtualBasket" technology in ureteral and renal stones.

METHODS

160 Patients were randomly assigned to holmium laser lithotripsy with or without the "VirtualBasket" technology in ureteric or renal cases (40 per 4 groups). All procedures were performed by four experienced urologists. The Quanta System Cyber Ho 100W laser generator with 365 μm fibers was used for all of the ureteral cases, whereas, 272 μm fibers were used for all of the cases in the renal pelvis. Demographic data, stone parameters, perioperative complications and success rates were compared. A statistical analysis was carried out to assess patients data and outcomes. All of the reported p-values were obtained with the two-sided exact method at the conventional 5% significance level. The degree of stone retropulsion was graded on a Likert scale from zero (no retropulsion) to 3 (maximum retropulsion).

RESULTS

All groups were comparable in terms of age, and pre-operative stone size (ureter stone size: 1.2 vs. 1.1 cm; renal pelvis stone size: 1.55 vs. 1.62 cm). Compared to the regular mode, the "VirtualBasket" technology was associated with significantly lower fragmentation time (mean time for ureteral stones: 20.4 vs. 16.1 minutes, p<0.05; mean time for renal stones: 28.7 vs. 19.8 minutes, p<0.05) and total procedural time (mean time for ureteral stones 49 vs. 35.7 minutes; mean time for renal stones 67.1 vs. 52.4 minutes). There were no significant differences in terms of energy delivered to the stones, intraoperative complications and success rate at 1 month. The "VirtualBasket" technology was associated with significantly lower retropulsion.

CONCLUSIONS

The "VirtualBasket" technology is associated with significantly lower fragmentation and procedural times. The reduced fragmentation time is a result of the significantly lower retropulsion of the stones during laser lithotripsy, which improves stone fragmentation efficiency.

Inadvertent Stone Migration During Pneumatic Lithotripsy: Still a Conundrum in the 21st Century

Currently, an ideal gadget to stop retrograde stone migration remains a holy grail, and the hunt for such a device is still ongoing in the 21st century. The quest for an ideal instrument is driven by the need to reduce cost, minimize ancillary procedure rates, reduce the device's operative time, and improve the stone-free rate. The purpose of the present review is to provide an update on the use of preventive measures that are used to stop retrograde stone migration during pneumatic lithotripsy for ureteric stone management.

Optimal management of large proximal ureteral stones (>10 mm): A systematic review and meta-analysis of 12 randomized controlled trials

OBJECTIVES

To develop an evidence base to guide clinicians treating adults with large proximal ureteral stones (LPUS) greater than 10 mm.

METHODS

A systematic search of PubMed, EMBASE, and Cochrane Library was conducted to identify randomized controlled trials (RCT) concerning different LPUS management techniques including laparoscopic ureterolithotomy (LU), percutaneous nephrolithotomy (PCNL) and ureteroscopic lithotripsy (URL) up until March 2020. We followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis statement when searching and determining inclusion. All included articles were quality assessed and the data analyses were conducted with Review Manager (5.3).

RESULTS

12 RCTs involving 1416 patients met our eligibility criteria and were analyzed. Of these participants, 44.6% (n = 632) underwent URL, 25.5% (n = 361) PCNL, and 29.9% (n = 423) LU. Pooled analysis revealed that URL had a significantly lower stone-free rate (SFR) compared to PCNL and LU (both with p < 0.05). URL had a significantly higher ureteral injury rate compared to LU (Relative risk (RR) = 5.27, 95% confidence interval (CI) 1.52 to 18.22, p = 0.009) and PCNL (RR = 4.11, 95% CI 1.03 to 16.34, p = 0.04). However, no significant differences were found between PCNL and LU in terms of SFR or overall complications, both with p > 0.05. URL initially costs less than PCNL (Weighted mean difference (WMD) -597.35US$, 95% CI -823.10 to -371.60, p < 0.00001), but being less effective creates greater demand for repeat or ancillary treatments compared to LU (RR 15.65, 95% CI 2.11-116.12, p = 0.007) and PCNL (RR 8.86; 95% CI 3.19-24.60; p < 0.00001).

CONCLUSIONS

Both PCNL and LU appear more effective and safer than URL for LPUS; although, LU has higher risk of urine leakage and is more likely incur trauma which requires additional support. However, caution must be taken because this recommendation is based upon a very limited number of clinical studies, and even fewer comparing flexible ureteroscopic technologies. Further prospective real-world studies or RCTs comparing flexible URL, LU and PCNL are required, as well as an in depth analysis of the hidden costs involved in unsuccessful URL treatments.

Worldwide Use of Antiretropulsive Techniques: Observations from the Clinical Research Office of the Endourological Society Ureteroscopy Global Study

INTRODUCTION

Retropulsion, defined as unintended migration of a stone under the influence of the fragmentation device in ureteroscopy (URS) procedures, occurs in 2% to 60% of the cases. Antiretropulsive devices (ARDs) have been studied in experimental and small clinical studies. The current study aims at describing the worldwide usage of ARD and the outcomes related to their usage.

METHODS

The Clinical Research Office of the Endourological Society URS Global Study enrolled 11,885 patients who underwent URS and stone fragmentation for ureteral and/or renal stones. Of the 11,885 treated patients, 9877 were treated for ureteral stones, and data were available on stone migration and ARD use.

RESULTS

Of all procedures, 14.5% were performed with the use of an ARD. Less stone migration (-2.0%; p = 0.050), higher stone-free rates (SFRs) (2.8%; p < 0.001), and shorter length of stay (-4.7%; p = 0.001) were observed in the antiretropulsive group.

CONCLUSIONS

When an ARD is used during URS, less migration, higher SFRs, and shorter length of hospital stay are observed. This effect is independent from baseline differences and corrected for other treatment characteristics.

Intracorporeal lithotripsy

Since the introduction of ESWL, PNL and URS during the early 1980s the application rate of ESWL has declined while those of PNL and URS have increased. This is mainly due to the facts that instruments and techniques for Intracorporeal Lithotripsy (IL) have made a continuous progress. This review shows that today an array of options for IL within the entire urinary tract is available to treat stones in a perfect minimal invasive way. At the same time further improvements of IL are already visible.

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.

The economics of stone disease

The rising prevalence of kidney stone disease is associated with significant costs to healthcare systems worldwide. This is in part due to direct procedural and medical management costs, as well as indirect costs to health systems, patients, and families. A number of manuscripts evaulating the economics of stone disease have been published since the 2008s International Consultation on Stone Disease. These highlight costs associated with stone disease, including acute management, surgical management, and medical management. This work hopes to highlight optimization in care by reducing inefficient treatments and maximizing cost-efficient preventative strategies.

Clinical significance of residual fragments in 2015: impact, detection, and how to avoid them

PURPOSE

Residual fragments are common after stone treatment. Little is known about clinical outcomes relevant to the patient. This comprehensive review of the literature highlights the impact of residual fragments, modes of detection, and treatment strategies to avoid residual fragments in shock wave therapy, ureteroscopy, and percutaneous nephrolithotomy.

METHODS

A comprehensive review of current literature was performed using PubMed(®), MEDLINE(®), Embase™, Ovid(®), Google Scholar™, and the Cochrane Library. Publications relevant to the subject were retrieved and critically appraised.

RESULTS

Residual fragments after treatment for urinary stones have a significant impact on a patient's well-being and future course. (Ultra-) low-dose non-contrast computed tomography detects small residuals most reliably. In shock wave lithotripsy, adherence to basic principles helps to improve results. Various techniques and devices facilitate complete stone clearance in conventional and miniaturized percutaneous nephrolithotomy and (flexible) ureteroscopy. Promising new technologies in shock waves, lasers, and robotics (and potentially microrobotics) are on the horizon.

CONCLUSIONS

Residual fragments are relevant to patients. Contemporary treatment of urolithiasis should aim at complete stone clearance.

Xenx (Xenolith): preliminary considerations of a new "all-in-one" ureteral guidewire and anti-repulsion device

A new anti-retropulsion device for the endoscopic treatment of ureteral stones was evaluated for safety and potential efficacy. The Xenx™ (Rocamed, Monaco-Montecarlo) is an anti-retropulsion device that operates as a normal hydrophilic guidewire when "closed" and as a nitinol ureteral mesh when "open". We performed semirigid ureterorenoscopy and Ho:YAG Laser lithotripsy in 15 patients, with a single ureteral stone. For each procedure, the papilla was negotiated with the Xenx™, the radiopaque markers were positioned over the stone via direct visualization and the device was opened under fluoroscopic control. The ureteroscope was then retracted and reinserted beside the Xenx™. At the end of the procedure, the Xenx™ was closed, and a ureteral catheter was coaxially placed and left for 24-48 h post-operation. We evaluated device positioning success with respect to pushability, ease of deployment, full expansion and fitting with the ureteral walls, kink resistance and stone retention capabilities during lithotripsy and device retrieval. Operative time, post-operative complications (Clavien-Dindo scale), ultrasound kidney stone-free rate and the hydronephrosis grade, were also recorded. At 4 weeks post-operation, the stone-free rate was assessed via non-contrast computed tomography with 1-mm slices. All procedures were successfully accomplished without complications according to the Clavien-Dindo scale. In all the cases, Xenx™ was inserted successfully past the stone and opened over it. In 4/15 cases (27%) some difficulties in pushability and kink resistance were recorded. In no case stone fragment basketing was performed. The median operative time was 24 min. At hospital discharge, 14/15 patients (93%) were kidney stone-free. At 4 weeks, the NCCT stone-free rate was 100%. This study demonstrated that the Xenx™ is safe and effective in terms of the stone-free rate, complications and operating time. Moreover, use of the Xenx™ allows the use of a basket or guide wire to be avoided.

Optimizing use of the holmium:YAG laser for surgical management of urinary lithiasis

The holmium:yttrium aluminum garnet (Ho:YAG, holmium) laser is an intracorporeal lithotrite that is widely used in the surgical management of urinary lithiasis. The Ho:YAG laser is capable of fragmenting urinary stones of all compositions while maintaining a wide margin of safety. The 2140-nm wavelength of energy is transmitted from the generator to the stone using specialized silica optical fibers. The effectiveness of the laser can be impacted by the type of laser fiber used, the pulse energy and frequency settings, and the composition of the stone. This paper provides an overview of Ho:YAG laser fibers utilized for lithotripsy during ureteroscopy. We will also review current data regarding optimal energy settings and discuss our experience with different fragmentation techniques.

Antiretropulsion devices

PURPOSE OF REVIEW

Stone migration during the treatment of ureteral stones can prove frustrating and increases both healthcare cost and patient morbidity. Antiretropulsion devices have been engineered to prevent stone migration.

RECENT FINDINGS

Improvements in antiretropulsion devices allow for efficient prevention of stone migration during ureteroscopic lithotripsy with minimal adverse effects or complications. Multiple devices are now available each with advantages and disadvantages. New devices are currently engineered to prevent stone migration and maintain ureteral access. Antiretropulsion devices appear to be cost-effective to prevent stone migration during intracorporeal lithotripsy.

SUMMARY

Antiretropulsion devices have been safely and effectively used during ureteroscopic procedures. These tools increase stone-free rates, decrease morbidity and new studies have demonstrated their cost-effectiveness.

Clinical efficacy, safety, and costs of percutaneous occlusive balloon catheter-assisted ureteroscopic lithotripsy for large impacted proximal ureteral calculi: a prospective, randomized study

PURPOSE

To evaluate the clinical efficacy, safety, and costs of percutaneous occlusive balloon catheter-assisted ureteroscopic lithotripsy (POBC-URSL) for large impacted proximal ureteral calculi.

PATIENTS AND METHODS

156 patients with impacted proximal ureteral stones ≥1.5 cm in size were randomized to ureteroscopic lithotripsy (URSL), POBC-URSL, and percutaneous nephrolithotomy (PNL) group between May 2010 and May 2013. For URSL, the calculi were disintegrated with the assistance of anti-retropulsion devices. POBC-URSL was performed with the assistance of an 8F percutaneous occlusive balloon catheter. PNL was finished with the combination of an ultrasonic and a pneumatic lithotripter. A flexible ureteroscope and a 200 μm laser fiber were used to achieve stone-free status to a large extent for each group. Variables studied were mean operative time, auxiliary procedure, postoperative hospital stay, operation-related complications, stone clearance rate, and treatment costs.

RESULTS

The mean lithotripsy time for POBC-URSL was shorter than URSL, but longer than PNL (42.6±8.9 minutes vs 66.7±15.3 minutes vs 28.1±6.3 minutes, p=0.014). The auxiliary procedure rate and postoperative fever rate for POBC-URSL were significantly lower than URSL and comparable to PNL (p<0.01, p=0.034). POBC-URSL was superior to URSL with regard to the stone clearance rate at 3 days postoperatively, and as good as PNL (98.1% vs 75.0% vs 96.2%, p<0.01). The postoperative hospital stay and hematuria rate were lower in POBC-URSL group than PNL group and similar to URSL group (p=0.016, p<0.01). The treatment costs were lowest in POBC-URSL group ($1205.0±$113.9 vs $1731.7±$208.1 vs $2446.4±$166.4, p=0.004).

CONCLUSIONS

For large impacted proximal ureteral calculi, POBC-URSL was associated with a higher stone clearance rate, fewer complications and costs. POBC-URSL combined the advantages of URSL and PNL.

Pushing the boundaries of ureteroscopy: current status and future perspectives

Substantial advances in ureteroscopy have resulted in the incorporation of this procedure into routine urological practice in many centres worldwide. Subsequently, an abundance of clinical data and technological progression have enabled the development of novel solutions that have increased the efficacy of ureteroscopy, and reduced associated morbidity and costs. In addition the indications for this retrograde approach have been expanded, and pyelocalyceal diverticulum, infundibular stenosis, urolithiasis in pregnant women or in patients with urinary diversions, as well as upper urinary tract tumours can now be managed using this methodology. New endoscopes are continuously developed, with different manufacturers choosing various technical solutions to further increase the efficacy and safety-and sometimes decrease costs-of ureteroscopy, including miniaturization, inclusion of digital optical systems and dual working channels, and the introduction of disposable apparatus. The holmium laser, currently the most-versatile energy source available, enables tissue incision, tumour ablation, and intracorporeal lithotripsy. Modern ancillary instruments are diverse, flexible, and durable, and novel devices used in daily clinical practice can minimize ascendant migration of stone fragments and, therefore, decrease the failure rate of the retrograde ureteroscopic approach. However, the peak of ureteroscopy evolution seems to remain distant, with further improvement of endoscopes and ancillary instruments, and robot-assisted ureteroscopy representing only some of the areas in which future developments are possible.