Single-use flexible ureteropyeloscopy: a systematic review

Thulium fiber laser vs Ho:YAG in RIRS: a prospective randomized clinical trial assessing the efficacy of lasers and different fiber diameters (150 µm and 200 µm)

INTRODUCTION

The aims of the study: (1) to compare the Super Pulse Thulium Fiber Laser (SP TFL) and the holmium: yttrium-aluminium-garnet (Ho:YAG) lasers in retrograde intrarenal surgery (RIRS); (2) to compare the efficacy of SP TFL laser fibers of different diameters (150 μm and 200 μm).

METHODS

A prospective randomized single-blinded trial was conducted. Patients with stones from 10 to 20 mm were randomly assigned RIRS in three groups: (1) SP TFL (NTO IRE-Polus, Russia) with fiber diameter of 150 μm; (2) SP TFL with 200-μm fiber; and (3) Ho:YAG (Lumenis, USA) with 200-μm fiber.

RESULTS

Ninety-six patients with kidney stones were randomized to undergo RIRS with SP TFL using a 150-μm fiber (34 patients) and a 200-μm fiber (32 patients) and RIRS with Ho:YAG (30 patients). The median laser on time (LOT) in the 200-μm SP TFL group was 9.2 (6.2-14.6) min, in 150-μm SP TFL-11.4 (7.7-14.9) min (p = 0.390), in Ho:YAG-14.1 (10.8-18.1) min (p = 0.021). The total energy consumed in 200-μm SP TFL was 8.4 (5.8-15.2) kJ; 150-μm SP TFL - 10.8 (7.3-13.5) kJ (p = 0.626) and in Ho:YAG-15.2 (11.1-25.3) kJ (p = 0.005).

CONCLUSIONS

Irrespective of the density, RIRS with SP TFL laser has proven to be both a safe and effective procedure. Whilst the introduction of smaller fibers may have the potential to reduce the duration of surgery, SP TFL results in a reduction in the LOT and total energy for stone ablation in RIRS compared with Ho:YAG.

Flexible Ureteroscopy: Global User Experience Using Disposable Devices

INTRODUCTION

Renal stone treatment through flexible ureteroscopy is widely established and successful. Ureteroscopes can broadly be classified into reusable and single-use disposable devices, each with their own advantages. Disposable scopes are cheaper to buy, maintain, and dispose of but may have a greater environmental impact and long-term cost. To establish the collective views of urologists, we conducted a multicentre, global study to demonstrate users' experience with single-use flexible ureteroscopes.  Methods: An online nine-question survey was distributed to urologists globally through email and social media platforms. Questions focused on user grade, experience, location, general opinion, advantages, disadvantages, and estimated cost of a single-use flexible ureteroscope. All responses were collated over a three-day period and analysed using descriptive statistics.

RESULTS

A total of 69 responses were received; the majority of responses were from the UK (75%), and most were consultants (64%). Two-thirds of those surveyed had used a single-use scope on a patient, and 95% of them stated they enjoyed using it, citing excellent vision and reduced need for maintenance. The majority (52%) stated that widespread adoption of disposable scopes was limited due to their prohibitive expense, with an average, sterling-converted responder-estimated cost of £991 (£100-£6000) per reusable scope.

CONCLUSION

Most urologists enjoyed using disposable scopes, finding them comparable or better than reusable devices. However, the initial cost can be prohibitive in certain centres. The potential environmental impact is a further concern as this remains largely unknown for now. In the meantime, it is likely that stone units will continue to use a combination of single-use and reusable scopes, considering their individual needs and budgets as well as local availability and price.

Influencing factors of acute kidney injury following retrograde intrarenal surgery

PURPOSE

To investigate the influencing factors of acute kidney injury (AKI) following retrograde intrarenal surgery (RIRS).

METHODS

The data of patients who underwent RIRS for kidney stones between January 2018 and June 2022 at two tertiary centers were retrospectively analyzed. Demographic data of patients were obtained. According to kidney disease: Improving Global Outcomes (KDIGO) criteria, those with and without AKI were divided into two groups. Preoperative, intraoperative, and postoperative predictive factors of patients were investigated between the groups. In addition, the influencing factors of AKI were examined by multivariate analysis.

RESULTS

This study included 295 (35.7%) women and 532 (64.3%) men. The mean age was 50.03 ± 15.4 years (range 18-89), and mean stone size was 15.5 ± 6.1 mm (range 6-47). Overall, 672 of patients (81.3%) were stone-free after the initial treatment. According to KDIGO, 110 of patients (13.3%) had AKI during the postoperative period. Univariate analysis showed that stone size (P = .003), previous stone surgery (P = .010), renal malformations (P = .017), high operative time (P =  < .001), high preoperative creatinine value (P = .036), intraoperative complications (P = .018), and postoperative urinary tract infection (P = .003) had significant influence on the AKI after RIRS. Multivariate analysis excluded previous stone surgery, high preoperative creatinine value, renal malformations, and intraoperative complications from the logistic regression model, whereas other factors maintained their statistically significant effect on AKI, indicating that they were independent predictors.

CONCLUSIONS

Stone size, operative time, postoperative urinary tract infection, and diabetes mellitus are significant predictors of AKI. During RIRS, urologists should consider the factors that increase the risk of AKI and evaluate the treatment outcomes based on these factors.

Single-use versus conventional reusable flexible ureteroscopes - an evaluation of the functional parameters

The purpose of single-use flexible ureteroscopes (su-fURS) was to overcome the limitations of conventional reusable ureteroscopes in terms of maneuverability and maintenance. We aimed to perform a systematic literature review on available su-fURS performance versus conventional reusable fURS focusing on clinical data. A systematic research using Pubmed was performed evaluating single-use fURS and reusable fURS in urinary tract stone disease, including prospective assessments and case series. This review aimed to provide an overview of single-use and disposable flexible ureteroscopes and to examine and compare their capabilities (deflection, irrigation, optical properties). We included 11 studies, where the single-use fURS were compared to the reusable fURS. The studies with single-use ureteroscopes included data on LithoVue (Boston Scientific), The Uscope UE3022 (Pusen, Zhuhai, China), NeoFlex-Flexible, (Neoscope Inc San Jose, CA), 23 YC-FR-A (Shaogang). For reusable ureteroscopes, data were included on three models, two digital (Karl Storz Flex-XC and Olympus URF-Vo) and one fiber optic (Wolf-Cobra). There were no significant differences in stone-free rate, procedure duration, or functional capabilities between single-use fURS and reusable fURS. The systematic literature review analyzed operative time, functional capabilities, stone-free rates, and postoperative complications of the ureteroscopes, and a special chapter about renal abnormalities to emphasize that they are a good choice having a high proportion of stone-free rates and few risks, particularly in treating difficult-to-access calculi. Single-use fURS demonstrate a comparable efficacy with reusable fURS in resolving renal lithiasis. Further studies on clinical efficacy are needed to determine whether single-use fURS will reliably replace its reusable counterpart.

Clinical Utility of a Single-Use Flexible Cystoscope Compared with a Standard Reusable Device: A Randomized Noninferiority Study

Objective: A noninferiority assessment of single-use digital flexible cystoscopy (FC) compared with standard reusable FC for bladder cancer surveillance, and investigation of lower urinary tract symptoms. Patients and Methods: Patients requiring FC who met inclusion criteria were randomly assigned to have their procedure performed using a single-use cystoscope (Ambu^® aScope™ 4 Cysto System) or a standard reusable cystoscope (Olympus CYF-VH flexible video cystoscope). Primary outcomes were noninferiority of the single-use cystoscope, in terms of effective procedure completion rate, image quality, light quality, and maneuverability. Secondary objectives compared safety, operative, and perioperative time. The noninferiority margin was set at -10%. Results: One hundred one patients completed the study (n = 50 trial, n = 51 control). All primary outcomes demonstrated noninferiority of the single-use cystoscope, compared with standard reusable FC. Effective completion rate, image quality, light quality, and maneuverability between single-use and reusable cystoscopes were 100% and 98% (confidence interval [CI]: -0.059 to 0.019); 96% and 100% (CI: -0.014 to 0.092); 98% and 100% (CI: -0.018 to 0.058); and 98% and 100% (CI: -0.018 to 0.058). There was no difference in operation time (p = 0.415) or total theater use time (p = 0.441) between groups. Adverse event rates were 4.08% and 4.16% in the trial group and control groups, respectively. Conclusion: The single-use Ambu flexible cystoscope is noninferior to standard FC in terms of procedure completion and light quality, image quality, and maneuverability. Single-use flexible cystoscopes are an effective and safe alternative to reusable flexible cystoscopes and may act as a suitable alternative or adjunct in the urologist's armamentarium.

Hybrid flexible ureteroscopy strategy in the management of renal stones - a narrative review

The introduction of single-use flexible ureteroscopes (suFURSs) in daily practice tends to overcome the main limitations of reusable ureteroscopes (reFURSs), in terms of high acquisition costs, maintenance, breakages and repairing costs, reprocessing and sterilization, as retrograde intrarenal surgery (RIRS) is promoted as first-line treatment of renal stones in most cases. A hybrid strategy implies having both instruments in the armamentarium of endourology and choosing the best strategy for cost-efficiency and protecting expensive reusable instruments in selected high-risk for breakage cases such as large stones of the inferior calyx, a steep infundibulopelvic angle or narrow infundibulum, or abnormal anatomy as in horseshoe and ectopic kidney. In terms of safety and efficiency, data present suFURSs as a safe alternative considering operating time, stone-free, and complication rates. An important aspect is highlighted by several authors about reusable instrument disinfection as various pathogens are still detected after proper sterilization. This comprehensive narrative review aims to analyze available data comparing suFURSs and reFURSs, considering economic, technical, and operative aspects of the two types of instruments, as well as the strategy of adopting a hybrid approach to selecting the most appropriate flexible ureteroscope in each case.

Contributions to expenditure in endoscopic stone management: a costly process

No comprehensive cost estimates exist for performing ureteropyeloscopy (URS), which is increasingly utilised as a treatment of upper tract urolithiasis in Australia. To estimate expenditure associated with URS in an Australian public hospital setting and determine factors contributing to increased cost. Patients who underwent flexible URS for urolithiasis over a 2-year period at a Victorian public health site were included. Data describing demographics, stone factors, disposable equipment and admission length were retrospectively collected. Procedures were performed using reusable flexible scopes. Previously validated costing models for cystoscopic stent extraction, theatre and recovery per hour and ward admission were used to attach cost to individual episodes. The cost of emergency stent insertion was beyond the scope of this study. 222 patients underwent URS; the combined total number of procedures was 539, comprising 202 stent extractions and 115 stent insertions in addition to 222 URS. Mean procedural cost was $2885 (range $1380-$4900). Mean episode cost excluding emergency stent insertion was $3510 (range $1555-$7140). A combination of flexible scopes, operative time and disposable equipment accounted for nearly 90% of the total procedural cost. Significant cost is associated with URS for treatment of renal and ureteric stones. A large burden of the cost is time in theatre, equipment and the need for multiple associated procedures per episode. Utilising other available treatments such as extracorporeal shockwave therapy (SWL) where appropriate may reduce the financial burden of URS and associated procedures.

Rigid ureteroscopic lithotripsy in the lateral decubitus position for upper urinary tract stones

Background

The current study aimed to assess a novel ureteroscopic technique developed for treating upper urinary calculi based on a specially designed lateral decubitus body position that could avoid stone loss by adjusting to the effects of gravity.

Methods

This retrospective study examined patients with upper urinary calculi who were surgically treated from November 2008 to January 2020, using a new body position and a rigid ureteroscope. Clinical outcomes, stone-free rates, operative times and complications were evaluated, and factors that could influence treatment success were determined.

Results

In total, 1080 patients were included, and 1145 operations were performed. The maximum calculus diameters were 11.22 ± 5.01 mm. Operative times were 48.60 ± 27.44 min. A total of 1042 cases were successfully treated, with a stone-free rate of 91.00%. Multivariate analysis showed that female sex (OR = 2.135, 95% CI 1.332–3.422, P = 0.002), thin scope standby (OR = 1.643, 95% CI 1.074–2.514, P = 0.022), laser lithotripsy (OR = 5.087, 95% CI 2.400–10.785, P = 0.000) and stone size (OR = 0.946, 95% CI 0.912–0.981, P = 0.003) were independently associated with stone-free outcomes. In total, 2 ureteral perforations, 2 ureteric avulsions and 4 urosepsis cases were observed, but were all cured without sequelae.

Conclusions

Ureteroscopic lithotripsy in the lateral decubitus position is a safe and effective technique for treating upper urinary tract calculi, especially upper ureteral calculi.

Single-Use vs. Reusable Digital Flexible Ureteroscope to Treat Upper Urinary Calculi: A Propensity-Score Matching Analysis

Objective: The purpose of this research was to compare the treatment outcomes and costs of a single-use and reusable digital flexible ureteroscope for upper urinary calculi.

Methods: Four hundred forty patients with reusable digital flexible ureteroscope and 151 patients with single-use flexible digital ureteroscope were included in this study. Through exclusion and inclusion criteria and 1:1 propensity-score matching analysis based on baseline characteristics, ultimately, 238 patients (119:119) were compared in terms of treatment outcomes. The cost analysis was based on the costs of purchase, repair, and reprocessing divided by the number of all procedures in each group (450 procedures with reusable digital flexible ureteroscope and 160 procedures with single-use digital flexible ureteroscope).

Results: There was no statistical significance in mean operation time (P = 0.666). The single-use digital flexible ureteroscope group has a shorter mean length of hospital stay than the reusable digital flexible ureteroscope group (P = 0.026). And the two groups have a similar incidence of postoperative complications (P = 0.678). No significant difference was observed in the final stone-free rate (P = 0.599) and the probability of secondary lithotripsy (P = 0.811) between the two groups. After 275 procedures, the total costs of a single-use flexible ureteroscope would exceed the reusable flexible ureteroscope.

Conclusion: Our data demonstrated that the single-use digital flexible ureteroscope is an alternative to reusable digital flexible ureteroscopy in terms of surgical efficacy and safety for upper urinary calculi. In terms of the economics of the two types of equipment, institutions should consider their financial situation, the number of FURS procedures, the volume of the patient's calculus, surgeon experience, and local dealerships' annual maintenance contract when making the choice.

Comparison Between Single-Use Flexible Ureteroscope and Reusable Flexible Ureteroscope for Upper Urinary Calculi: A Systematic Review and Meta-Analysis

Objective: This article explores the differences in the effectiveness and safety of the treatment of the upper urinary calculi between single-use flexible ureteroscope (su-fURS) and reusable flexible ureteroscope (ru-fURS).

Methods: We systematically searched PubMed, Embase, Cochrane Library, Scopus database, and CNKI databases within a period from the date of database establishment to November 2020. Stata 16 was used for calculation and statistical analyses.

Results: A total of 1,020 patients were included in the seven studies. The statistical differences were only found in the Clavien–Dindo grade II postoperative complication [odds ratio (OR) 0.47; 95% CI 0.23–0.98; p = 0.04]. No significant statistical differences were observed in operative time (OT), estimated blood loss (EBL), length of hospital stay (LOS), and stone-free rate (SFR).

Conclusion: Our meta-analysis results demonstrate that su-fURS, compared with ru-fURS, has similar effectiveness and better security for treating upper urinary calculi.

Efficiency of retrograde intrarenal surgery in lower pole stones: disposable flexible ureterorenoscope or reusable flexible ureterorenoscope?

PURPOSE

The primary aim of this study to comparison of reusable and disposable flexible ureterorenoscope (fURS) efficiency in lower pole renal stone disease management. In addition, the secondary goal of this study was to evaluate the factors affecting stone-free rates (SFR) in lower pole stones.

MATERIALS AND METHODS

A prospective case-control study utilizing data from 122 consecutive ureteroscopic cases. The patients were divided into two groups according to the ureterorenoscope employed in the surgical intervention as disposable fURS (Group1, n:52) and reusable fURS (Group 2, n:70). Demographic characteristics, stone size, infundibulopelvic angle (IPA), SFR, hospitalization time, intraoperative complication rate (CR), operative time, preoperative or postoperative JJ stenting, and postoperative CR were analyzed.

RESULTS

There was no statistical difference between the demographic and renal stone-related data between the groups. Likewise, no difference is observed in term of intraoperative and postoperative outcomes such as fluoroscopy time, CR, and hospitalization time between the groups. Although SFR was higher in the disposable fURS group, there was no difference statistically. However, the operative time was longer in reusable fURS Group (47.02 ± 9.91 min in Group 1, and it was 57.97 ± 14.28 in Group 2) (p: 0.001). The multivariate regression analysis result to evaluate the factors of effect to operative time; the use of disposable fURS was associated with a 10.95-min decrease in procedure duration (p < 0.001).

CONCLUSIONS

Disposable fURS and reusable fURS have similar clinical efficiency and complication rates in the treatment of lower calyceal stones with RIRS. Nevertheless, disposable fURS is a useful treatment option for increased stone volume due to the advantages such as shorter operative time.

Can the introduction of single-use flexible ureteroscopes increase the longevity of reusable flexible ureteroscopes at a high volume centre?

OBJECTIVES

To assess whether the introduction of single use flexibles ureteroscopes (su-fURS) at our high-volume centre had an advantageous impact on the turn-over and breakage rates of reusable fURS (re-fURS).

METHODS

We analysed re-fURS number of usages and breakages at our centre between February 2015 and December 2018. We recorded the number of usages for analysed scope between the first usage until a breakage requiring reconditioning. Usage count was restarted following each reconditioning episode. Since su-fURS (Lithovue, Boston Scientific, USA) were introduced at our center in September 2016, we had the chance to compare different re-fURS life cycles according to both su-fURS availability and usage intensity (i.e., number of su-fURS used during each re-fURS life cycle). We then explored the relationship between su-fURS usage intensity and reusable scope survival (i.e., number of utilizations before any breakage requiring reconditioning) using locally weighted scatterplot smoothing (LOWESS) approach.

RESULTS

Five different re-fURSs were employed at our centre, for a total of 1820 usages and 40 breakages requiring reconditioning. The overall mean (SD) number of usages before breaking was 40 (22). After su-fURS introduction, mean (SD) re-fURS number of usages increased from 35 (22) to 49 (20), (+ 40%, p = 0.02). The relationship between su-fURS usage intensity and reusable scopes survival showed a linear survival increase after 10 or more su-fURS scopes were used per life cycle.

CONCLUSIONS

The life cycle of re-fURS increased by 40% after the introduction of su-fURS. Ten or more used su-fURS per life cycle were associated with increased re-fURS survival.

Reusable, Single-Use, or Both: A Cost Efficiency Analysis of Flexible Ureterorenoscopes After 983 Cases

Objectives: To determine which flexible ureterorenoscopy program would be most cost-efficient in our center, a cost efficiency analysis and a formula to assess cost efficiency feasibility of a hybrid model were performed. Methods: Total cost per case of reusable flexible ureterorenoscopes (rfURS) was retrospectively calculated and compared with two single-use flexible ureterorenoscopes (sufURS) marketed. A mathematical formula was developed from our data to identify the necessary increase of use of rfURS (NIU-rfURS) to be cost-efficient in a hybrid system utilizing sufURS for only high-risk-of-breakage cases. Results: In 57 months, 983 procedures were performed using 4 digital rfURS (Flex-XC; Storz), necessitating 45 repairs, with a total repair cost of €256.809. Including the capital investment of €24.000 per scope and €60 per sterilization cycle, the cost per case averaged €419 after 983 cases. Consistently using sufURS would have cost 55% to 127% more (respectively, Uscope PU3022^® and Lithovue^® at €650 and €950 manufacturer suggested retail price). On a per case analysis, the cost was initially extremely high, but declined to reach a plateau around €480 after ∼400 cases. After 155 or 274 procedures, a rfURS program appeared more cost-efficient than consistently using Lithovue or Uscope PU3022, respectively. Based on our data and formula, if we would hypothetically use Uscope PU3022 or Lithovue for 15% of the cases, the NIU-rfURS is, respectively, 28% or 74% (∼6 or 16 cases). The NIU-rfURS increases exponentially with an increased use of sufURS. Conclusion: Consistently using rfURS is more cost-efficient than the constant use of sufURS after 155 to 274 cases. We describe the first mathematical formula that allows a calculation and feasibility assessment of using both reusable and disposable fURS. To identify whether a hybrid system may be a feasible cost-efficient alternative to a rfURS-only program, any center can calculate the NIU-rfURS by entering center-specific data in the formula.

Stone removing efficiency and safety comparison between single use ureteroscope and reusable ureteroscope: a systematic review and meta-analysis

Background

Urologists are gradually beginning to use single-use ureteroscopes (sufURSs), despite a lack of high-level evidence as to their efficacy and safety. This systematic review was registered on PROSPERO (no. CRD42020181808).

Methods

The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for studies published before October 1, 2020. Jadad score tools were used to evaluate the quality of the included randomized controlled trials (RCTs) and the Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the included nonrandomized studies. Two researchers independently extracted data according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) principles. A data synthesis was performed using Stata 15.0. Heterogeneity was mainly evaluated with I2 tests. In addition to funnel plots, Egger's and Begg's tests were used to detect publication bias. A sensitivity analysis was also performed. Stone-free rates and postoperative complications were the 2 primary outcomes; operation-time data were also extracted.

Results

Six studies (comprising 887 patients) containing the efficacy data and 5 studies (comprising 952 patients) containing the safety data that were finally included in the quantitative analysis. In relation to stone removal, no significant difference was found in terms of efficacy [Mantel-Haenszel statistic (M-H), relative risk (RR): 1.01, 95% confidence interval (CI): 0.96-1.07, P=0.658) or safety (M-H, RR: 1.30, 95% CI: 0.96-1.75, P=0.093) between the sufURS and the reusable flexible ureteroscope (rfURS), and no significant heterogeneity was found. A publication bias was detected in the efficacy comparison; however, the trim-and-fill analysis indicated that the original synthesis results remained stable.

Conclusions

In relation to stone removal, sufURSs were found to be comparable to rfURS, and no compromising complications were found. However, the results should be treated with caution due to limitations related to the small number of studies included in the analysis.

Comparison of single-use and reusable flexible ureteroscope for renal stone management: a pooled analysis of 772 patients

Flexible ureteroscopy is a common therapy for patients with renal calculi. In recent years, the prevalence of single-use flexible ureteroscope (FURS) use has been on the rise. Thus, several trials have been conducted to compare the efficacy between single-use and reusable FURS. The aim of this meta-analysis was to systematically assess the effectiveness and safety of single-use vs. reusable FURS in treating renal stones. PubMed, Web of Science, Cochrane Library and EMBASE were researched to identify relevant studies up to September 2019. Article selection was performed through the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria. The Newcastle-Ottawa Scale was applied to assess the methodological quality of non-randomized controlled trials, and the methodological quality of randomized controlled trials was evaluated using the Jadad scale. A total of five studies with 772 patients were included in the meta-analysis, including two randomized controlled trials, two single-centre prospective studies, and one prospective case-control trial. The pooled results showed that single-use FURS was associated with a higher stone-free rate (SFR) (OR: 1.50; 95% CI, 1.06–2.12; P=0.02) than reusable FURS. A significant difference was noted in operative time, and single-use FURS was associated with a longer operative duration (MD: 7.39 min; 95% CI, 1.75–13.03; P=0.01). No significant difference was noted in perioperative complications (OR: 0.97; 95% CI, 0.56–1.70; P=0.92). Subgroup analysis showed no significant difference in urinary tract infection (OR: 0.80; 95% CI, 0.44–1.46; P=0.46), stent migration (OR: 0.56; 95% CI, 0.19–1.65; P=0.30) or acute kidney injury (OR: 0.76; 95% CI, 0.16–3.57; P=0.73). Single-use FURS is an effective and safe alternative to reusable FURS for the management of renal stones.

LithoVue™ for renal stone therapy - a perfect fit for high volume academic centers; a retrospective evaluation of 108 cases

Background

Over the last few years the number of flexible ureterorenoscopies, used for renal stone treatment, has risen steadily. This was associated with an increase in costs for maintenance and repair of the fragile ureterorenoscopes used. To overcome this problem single-use devices have been introduced to the market. The aim of this study was to assess surgical outcome and workability for LithoVue™, a single-use flexible ureterorenoscope.

Methods

We retrospectively analyzed all flexible ureterorenoscopies performed at our department between January and October 2017. We included a total of 108 interventions for renal stone therapy, all performed using the single-use device LithoVue™. We assessed patients’ characteristics including stone size, count and location. We evaluated the surgical outcome, analyzing stone-free rates, reintervention rates, complication rates, as well as surgery time. Learning curve for single-use ureterorenoscopes was evaluated by comparing the surgical outcome between residents and consultants.

Results

The average time needed per intervention was 52,31 min ± 28,11. In 77 out of 108 (71,30%) patients we were able to remove all stones by a single intervention. In 8 patients (7,41%) intra- or postoperative complications occurred, none of which was graded higher than Clavien-Dindo III B. We did not find any statistical differences comparing the surgical outcome between residents and consultants. No technical difficulties occurred during surgery.

Conclusion

Single-use flexible ureterorenoscopes provide decent working properties resulting in good surgical outcome. Furthermore, they are proven to be easy to handle even for unexperienced surgeons, making them a feasible choice for high volume academic centers.

Urologic treatment of nephrolithiasis

PURPOSE OF REVIEW

The purpose of this review is to describe the options and recent developments in the urologic treatment of nephrolithiasis in children. The prevalence of nephrolithiasis in children has increased over time. The urologic treatment of nephrolithiasis ranges from observation to medical expulsive therapy with an alpha blocker for a stone in a ureter to a variety of procedures for stone removal.

RECENT FINDINGS

Observation for small, asymptomatic renal stones is a reasonable strategy in children. Medical expulsive therapy with an alpha blocker may have a beneficial effect for passage of ureteral stones in children. Extracorporeal shock wave lithotripsy (ESWL) remains an important treatment for nephrolithiasis in children. Advances in ureteroscopy with clearer digital imaging and single use ureteroscopes have made ureteroscopy more attractive. Percutaneous nephrolithotomy is a more invasive treatment modality but remains a good choice for children with large-stone burdens and instruments are getting smaller. Open or laparoscopic stone surgery should be reserved for unique cases.

SUMMARY

Nephrolithiasis is increasing in children with differing urologic management options depending on the clinical scenario. A shared decision-making process with discussion of risks and benefits should be used to help patients and families choose a treatment option.

Comparative investigation of reusable and single-use flexible endoscopes for urological interventions

In order to evaluate the technical adaptability of a type of disposable endoscope compared to reusable flexible endoscopes, in vitro and in vivo studies were conducted. A disposable digital ureteroscope ("chip on tip") and two reusable endoscopes were investigated with respect to spatial resolution, geometric distortion in air and water the maximum. Additionally, the clinical performance of the disposable device was tested during clinical procedures (n = 20). The disposable endoscope showed an optical resolution of 6.72 lines/mm at 10 mm distance, similar to the other devices. In comparison, the disposable endoscope showed a barrel-shaped image distortion in air of -24.2%, which is in the middle range, but was best under water (-8.6%). The bendability of 297° (275 µm fiber) and 316° (empty channel, 1.5 F basket) and the maximum irrigation (1 m: 58.1 ml/min, 2 m: 91.9 ml/min) were convincing. Clinically the maneuverability was very good in (13/20), good or satisfactory in (7/20). Visibility was evaluated as very good in (11/20), just in (1/20) either satisfactory or sufficient. The consistency of visibility was not affected in (19/20). In all cases there were no adverse events. The technical examination and clinical application of the disposable endoscope are of equal quality compared to reusable devices. Disposable endoscopes can be an alternative to reusable devices, but economic aspects such as reduction of repair costs, sterilization effort and additional waste must be taken into account.

Laser fibre, rather than the stone, may harm the scope: retrospective monocentric analysis of 26 pre- and intraoperative factors of flexible ureteroscope (fURS) damage

PURPOSE

The increasing number of flexible ureteroscopy procedures, the fragility of devices and their repair costs are a burden for urological departments worldwide. The objective was to investigate the impact of 26 pre- and intraoperative factors on reusable flexible ureteroscope (fURS) damage.

METHODS

All procedures were conducted with reusable fURS: Karl Storz Flex-X2 or Olympus URF-V. Statistical analysis was performed in RStudio (1.0.136) with Chi-square test and Mann-Whitney U tests (MWU).

RESULTS

In total, 416 flexible ureteroscopies, performed between September 2013 and June 2017, were analysed. 283 (68.03%) of these were for kidney stone surgery, and 133 (31.97%) for diagnostic purposes. In total, 39 (9.38%) devices were postoperatively deemed defective. The application of reusable laser fibre through fURS was more common in cases with documented defects [17/39 (43.59%) vs. 102/377 (27.06%), p = 0.047]. Other factors such as application of nitinol basket, biopsy via fURS, insertion of access sheath (UAS), as well as stone burden [median kidney stone maximal diameter: 6 mm (min 2.0; max 30.0) vs. 6 mm (min 1.0 vs. max 30.0)] showed no influence on fURS damage rate (p > 0.05). The infundibulopelvic angle (IPA) was steeper in cases with fURS damage as compared to cases without damage [median 44.0° (min 20.0; max 81.0) vs. 55.0 (min 7.0; max 122.0), p < 0.001].

CONCLUSIONS

Application of laser fibre via fURS can be considered as a risk factor of fURS damage. Stone burden, as well as the usage of not-sharp ended devices as nitinol baskets or forceps, is primarily not responsible for fURS damage.

Reusable flexible ureterorenoscopes are more cost-effective than single-use scopes: results of a systematic review from PETRA Uro-group

Clinical data suggest an equipoise between single-use (disposable) and reusable flexible ureterorenoscope (fURS) in terms of scope characteristics, manipulation, view and clinical outcomes. The procedural cost of reusable fURS is dependent on the initial and repair cost, maintenance and scope sterilization and on the number of procedures performed/repair. We conducted a systematic review on the procedural cost ($) of fURS based on the individual authors reported data on the number of procedures performed before repair and to see if it is a feasible option compared to single use fURS. A systematic review carried out in a Cochrane style and in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist using Medline, Scopus, CINAHL, EMBASE and Cochrane library for all English language articles. All papers on fURS cost analysis were searched from 2000-2018 (19 years), which mentioned the cost of fURS based on the number of procedures performed and the repairs needed (procedure/repair) as reported by the individual authors. Six studies reported on both the number of procedures performed with number of repairs needed and the cost calculated/procedure in the given time period. The number of uses/repair in various studies varied between 8-29 procedures and the cost per procedure varied between $120-1,212/procedure. A significant trend was observed between the decreasing cost of repair with the number of usages. With studies reporting on a minimum of 20 cases/repair the mean cost was around $200/procedure. This is contrast to the disposable scopes such as Lithovue ($1,500-2,000/usage) and Pusen ($700/usage). The cost of reusable fURS is low in centres performing a high volume of procedures. Similarly, when a reasonable volume of procedures is performed before scope repair, the cost is lower than the disposable scopes. Although, the disposable and reusable scopes seem to be comparable in terms of their performance, this review proves that reusable fURS are still more cost effective than disposable scopes.

Single use versus reusable digital flexible ureteroscopes: A prospective comparative study

OBJECTIVES

To compare the performance and surgical outcomes of two different single-use digital flexible ureteroscopes with a reusable video flexible ureteroscope.

METHODS

Patients undergoing retrograde flexible ureteroscopy at Nepean Hospital, Sydney, Australia, were included in this study. Three different flexible ureteroscopes were used in this study: (i) single-use digital LithoVue (Boston Scientific, Marlborough, MA, USA); (ii) single-use digital PU3022A (Pusen, Zhuhai, China); and (iii) reusable digital URF-V2 (Olympus, Tokyo, Japan). Visibility and maneuverability was rated on a 5-point Likert scale by the operating surgeon. Operative outcomes and complications were collected and analyzed.

RESULTS

A total of 150 patients were included in the present study. Of these, 141 patients had ureteroscopy for stone treatment, four for endoscopic combined intrarenal surgery and five for diagnostic/tumor treatment. There were 55 patients in the LithoVue group, 31 in the PU3022A group and 64 patients in the Olympus URF-V2 group. The URF-V2 group had higher visibility scores than both the single-use scopes and higher maneuverability scores when compared with the PU3022A. The LithoVue had higher visibility and maneuverability scores when compared with the PU3022A. There were no differences in operative time, rates of relook flexible ureteroscopes, scope failure or complication rates observed.

CONCLUSIONS

Single-use digital flexible ureteroscopes have visibility and maneuverability profiles approaching that of a reusable digital flexible ureteroscope. Single-use flexible ureteroscopes achieve similar clinical outcomes to the more expensive reusable versions.

Comparative medico-economic study of reusable vs. single-use flexible ureteroscopes

PURPOSE

Reusable flexible-ureteroscopes (fURS) require personnel and budget for processing and repairing, whereas single-use fURS were recently developed. After exclusive reusable fURS since 2011, we experienced high repair costs and single-use fURS were therefore introduced in mid-2017. We aimed to evaluate economic and practical advantages and disadvantages of reusable versus single-use fURS.

MATERIALS AND METHODS

First, we evaluated the incidence of breakage and repairs of reusable fURS in 2017. We assessed the overall operational costs of reusable fURS including purchase, processing, and repairing in our institution from 2011 to 2017. Following our experience, we created a model to compare operation costs/procedure of single-use fURS with reusable fURS depending on repair costs.

RESULTS

In 2017, repair costs of reusable fURS increased by 345% compared with the period 2011-2016, causing: a median unavailability per reusable fURS of 200 days/year (100-249), median number of functioning fURS 0/5-3/5 per operating day, while unavailability of reusable fURS had become the first reason for cancellation of procedure. Since it was introduced, single-use fURS accounted for 59% of the flexible ureteroscopy activity. Taking into account the costs of processing, maintenance and repair, in 2011-2016 versus 2017, the single-use fURS was cost-effective compared with the reusable fURS until the 22nd procedure versus the 73rd procedure, respectively.

CONCLUSIONS

After years of exclusive reusable fURS, the rising incidence of breakage not only increased maintenance costs but also hampered daily activity owing to unavailability of the devices. The introduction of single-use with reusable fURS provided substantial help to maintain our activity.

Steep Infundibulopelvic Angle as a New Risk Factor for Flexible Ureteroscope Damage and Complicated Postoperative Course

OBJECTIVE

The increasing number of flexible ureterorenoscopy (fURS) procedures, the fragility of devices, and their growing repair costs represent a substantial burden for urological departments worldwide. No risk factors of flexible ureteroscope damage have been identified so far. The objective of this study was to investigate the impact of infundibulopelvic angle (IPA) on device damage and on other intraoperative and postoperative factors such as length of hospital stay, surgical complications, stone-free rate (SFR), operation, and fluoroscopy time.

MATERIALS AND METHODS

In a retrospective monocentric study, IPA was measured based on intraoperative retrograde pyelography images taken during fURS. All procedures were conducted with modern reusable flexible ureteroscopes: Karl Storz Flex-X2 or Olympus URF-V. Statistical analysis was performed in RStudio (version 1.0.136) with the unpaired t-test and Mann-Whitney U test. Pearson correlation coefficient (Pearson's r) was measured whenever applicable.

RESULTS

In total, 381 fURS performed between September 2013 and March 2017 were analyzed: 260 (68.24%) for kidney stone operation and 121 (31.76%) for diagnostic purposes; of these, 38 (9.97%) devices were postoperatively deemed defective. IPA values were significantly steeper in cases with flexible ureteroscope damage compared to cases without damage (median 42.5 degrees vs 56.0, p < 0.001). Steeper IPA was significantly associated with the occurrence of Clavien-Dindo ≥2 complications (median 51.0 degrees vs 55.0, p = 0.005) as well as prolonged hospital stay (median 51.0 degrees vs 55.0, p = 0.014). No influence on SFR was observed (p > 0.05). IPA did not correlate with operation or fluoroscopy time.

CONCLUSIONS

Steep IPA can be considered the first risk factor predicting both flexible ureteroscope damage and an unfavorable postoperative course. A better understanding of damage mechanisms is the key for the proper indications to use costly single-use devices.