Clinical effectiveness of the PolyScope™ endoscope system combined with holmium laser lithotripsy in the treatment of upper urinary calculi with a diameter of less than 2 cm

Application of virtual endoscopic imaging to parapelvic cyst incision by flexible ureteroscopy: a multicenter retrospective cohort study

BACKGROUND

A three-dimensional (3D) reconstruction of the kidney, parapelvic cyst and the collecting system was conducted using the 3D Slicer software. The reconstructed image was used to form a virtual endoscope to assist flexible ureteroscopic incision and drainage was performed with a holmium laser for treating parapelvic cysts. The effectiveness of this assistive technique was assessed.

METHODS

This was a retrospective cohort study. The clinical information of 59 patients undergoing flexible ureteroscopic incision and drainage for parapelvic cysts in two medical centers was collected. 3D Slicer software reconstruction and virtual endoscopic imaging were performed for 28 cases. Before the operation, the best point for incision on the collecting system's mucosa was assessed by virtual endoscope imaging. Propensity score matching was adopted for the reconstructive and non-reconstructive groups.

RESULTS

After matching, the reconstructive group and non-reconstructive group both had 21 cases each. The operation time in the reconstructive and non-reconstructive groups was 38.81±5.01 and 51.00±18 minutes, respectively. Statistically significant differences existed between the two groups (t=7.024, P<0.001). No statistical significance was found in postoperative fever, immediate postoperative C reactive protein (CRP), length of postoperative hospital stay and cyst diameter three months after the operation.

CONCLUSIONS

The operator was provided with a more direct and real vision when 3D Slicer software reconstruction was adopted via virtual endoscopic imaging to assist flexible ureteroscopic parapelvic cyst incision. This helped reduce the operation time. Further follow-ups and observations are required to assess the long-term efficacy of flexible ureteroscopic parapelvic cyst incision.

WiScope® single use digital flexible ureteroscope versus reusable flexible ureteroscope for management of renal stones: a prospective randomized study

OBJECTIVES

To compare the clinical performance and surgical outcomes of the new digital single use flexible ureteroscope (WiScope^®) with a reusable digital flexible ureteroscope.

PATIENT AND METHODS

Our prospective study includes patients with renal stones less than 2 cm who underwent retrograde flexible ureteroscopy and laser lithotripsy. Patients were randomized into two groups: group A included patients who underwent laser lithotripsy using WiScope^® Single use digital flexible ureteroscope and group B included patients who underwent laser lithotripsy using reusable flexible ureteroscope. Image quality, deflection, ease of insertion, maneuverability, and overall performance were assessed using either a visual analog or Likert scale. Operative outcomes and complications were collected and analyzed in both groups.

RESULTS

A total of 242 patients were included in our study. There were 121 patients in the WiScope^® group and 121 patients in reusable ureteroscope group. The WiScope^® had higher maneuverability (9.3 ± 0.7 vs. 7.2 ± 0.8, P < 0.001) and less limb fatigue but had lower image quality when compared to reusable digital flexible ureteroscope (7.6 ± 0.9 vs. 9.2 ± 0.6, P < 0.001). There were no differences in operative time, complication rates and rates of relook ureteroscopy.

CONCLUSIONS

The WiScope^® single use flexible ureteroscope has comparable outcomes to the reusable flexible ureteroscope with regard to maneuverability, limb fatigue, and deflection. However, it has a lower image quality.

One-stage efficacy of single tract minimally invasive ECIRS in the improved prone frog split-leg position for staghorn stones

OBJECTIVE

To explore the feasibility, safety, and effectiveness of single tract minimally invasive endoscopic combined intrarenal surgery (stmECIRS) in the improved prone frog split-leg position for staghorn stones.

METHOD

A total of 83 patients with staghorn stones were retrospectively reviewed between January 2018 and June 2021. According to surgical procedure and position, patients were divided into a group of single tract minimally invasive percutaneous nephroscopy (stmPNL) in the prone position and a group of stmECIRS in the improved prone frog split-leg position (turned to the prone position after preset the flexible ureteroscope sheath in lithotomy position, meanwhile, bend both hips and knees to be frog abduction). Demographic characteristics, laboratory tests, stone characters, surgical information, stone-free rate (SFR), and perioperative complications were observed and analyzed.

RESULTS

There were no significant differences in demographic characteristics, changes level of Scr and Hb, stone size, radiation density, length of hospital stay, and operation time between the two groups. One-stage SFR in the stmECIRS group was significantly higher than that in the stmPNL group (84.4% vs. 57.9%) (P = 0.007), only 2 patients required blood transfusion after surgery (P = 0.862), and other postoperative complications were not statistically significant (P = 0.345).

CONCLUSIONS

StmECIRS in improved prone frog split-leg position has a higher one-stage SFR than stmPNL for staghorn renal stones, and without complications increased, which is a safe, efficient and feasible treatment.

Disposable Ureteroscopes in Urology: Current State and Future Prospects

Ureteroscopy is the most common surgical modality for stone treatment. Reusable flexible ureteroscopes are delicate instruments that require expensive maintenance and repairs. Multiple single use ureteroscopes have been developed recently to combat the expensive and time-intensive sterilization and repair of ureteroscopes. Although multiple studies have looked at different aspects of reusable and single use ureteroscopes, there is significant heterogeneity in performance measures and cost between the 2 categories, and neither has a clear advantage. Both can be used successfully, and individual and institution level factors should be considered when deciding which ureteroscope to use.

The effect of ideal urine culture time on urinary infections after flexible ureteroscopy: A match-pair case-control study

AIMS

To investigate the effect of the ideal period (Δ-day), which is a period between the sterile urine culture and initiation of flexible ureteroscopy (f-URS), on postoperative urinary tract infections (UTI) in our tertiary referral centre.

METHODS

After obtaining the approval of the local ethics committee, retrospective data were collected for all f-URS procedures performed between January 2017 and March 2019. Patients that developed UTI were matched in 1:1 proportion with patients that did not develop UTI based on their demographic and stone characteristics. The group of patients with postoperative UTI was compared with the control group.

RESULTS

A total of 916 f-URS cases that had all required data were analysed. Sixty-eight patients with postoperative UTI were determined and a total of 136 patients were included in the study after match-pair. We found that if the Δ-day is longer than 2 weeks, the possibility of postoperative urinary infection rates increases with statistical significance (P = .006). According to our subgroup analysis, postoperative UTI was more common if the Δ-day >14 days. ROC curve analysis provided a 14.5-day period as a cut-off value of Δ-day for postoperative UTI.

CONCLUSIONS

The present study is the first to examine the impact of the Δ-day for f-URS on postoperative UTIs. In brief, prolonging the Δ-day, especially if Δ-day >14 days, leads to an increase in the rates of postoperative UTI. We conclude that it is preferred to either perform the f-URS in the early period after the urine culture analysis or doing the urine culture analysis shortly before the surgery.

Precision Stone Surgery: Current Status of Miniaturized Percutaneous Nephrolithotomy

PURPOSE OF REVIEW

Innovations in lasers and surgical technology have led to a renewed interest in the miniaturization of percutaneous nephrolithotomy (PCNL). We review the different approaches and evidence on the efficacy of mini-PCNL.

RECENT FINDINGS

Mini-PCNL encompasses a range of techniques using tract sizes from 4.8 to 22 F to treat renal stones. The most common device uses irrigation to passively extract stones out of the sheath. Super-mini-PCNL incorporates active suction. Ultra- and micro-techniques reduce the tract to smaller diameters. Laser fragmentation is the main lithotripsy modality. Studies demonstrate an association with reduced complications, hospital stay, and increased tubeless rate. Drawbacks include longer operative times while stone-free rates for larger stones may be sub-optimal. Mini-PCNL has advantages of less trauma and the avoidance of nephrostomy tubes. Ambulatory surgery is feasible in select patients. Advances in laser lithotripsy and active suction have the potential to improve stone clearance and treat larger stones.

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.

Flexible ureteroscopy: reuse? Or is single use the new direction?

PURPOSE OF REVIEW

Single-use flexible ureteroscopes (su-fURS) aim at overcoming the main limitations of conventional reusable ureteroscopes in terms of acquisition and maintenance costs, breakages, and reprocessing. However, little data exist to date regarding the superiority of su-fURS at this regard. We aimed to perform a systematic literature review on available su-fURS performance with a focus on clinical data for all articles in the last 10 years.

RECENT FINDINGS

To date, more than 10 different su-fURS are available on the market, with different characteristics and performance. Some of these devices have top-level features, almost catching up with those observed in reusable flexible ureteroscopes. Clinical evidence is mainly available only for two models, LithoVue and Uscope PU3022, and to date it is not strong enough to support routine adoption and use of su-fURS, with a consequent lack of consensus of specific clinical indications. Cost-effectiveness analyses seem to indicate an economic disadvantage in the routine adoption of su-fURS. Environmental issues related to the use of su-fURS also remain to be inquired and addressed.

SUMMARY

Since their introduction, su-fURS have gained widespread popularity. Despite their ability at addressing reusable ureteroscope limitations, high-cost and a substantial lack of evidence are still limiting their routine adoption.

Cost comparison of single-use versus reusable flexible ureteroscope: A systematic review

Single-use flexible ureteroscopes (su-fURS) aim at overcoming the main limitations of conventional reusable flexible ureteroscopes (re-fURS) in terms of acquisition and maintenance costs, breakages, and reprocessing. We aimed to perform a literature review on available re-fURS and su-fURS performances with a focus on costs. A search of Medline, EMBASE, CINAHL, and Scopus databases was performed to identify articles published in English within the last 10 years addressing refURS and su-fURS characteristics, clinical, and cost data. Relevant studies were then screened, and the data were extracted, analyzed, and summarized. The Preferred Reporting Items for Systematic Reviews and Meta-analysis criteria were applied. A narrative synthesis was performed. To date, few studies have properly investigated the issue of costs in ureteroscopy. An important local and international variation in costs exists for both re-fURS and su-fURS in terms of acquisition, maintenance, and repair costs. Reusable scopes have high acquisition and ancillary (e.g. repair, involved personnel) costs, which are not considered in a pure su-fURS activity. However, only recently su-fURS were shown to have a similar efficacy as compared with reusable devices. In high-volume centers, with proper training for reusable ureteroscopes management, the cost per case of reusable and single-use scopes are overlapping ($1,212-$1,743 versus $1,300-$3,180 per procedure). There is a partial overlap in the ranges of costs for single-use and reusable scopes, which makes it important to precisely know the caseload, repair bills, and added expenses when negotiating purchase prices, repair prices, and warranty conditions for scopes.

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.

A comprehensive literature-based equation to compare cost-effectiveness of a flexible ureteroscopy program with single-use versus reusable devices

PURPOSE

To critically review all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes.

MATERIALS AND METHODS

A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. All factors potentially affecting surgical costs or clinical outcomes were considered. Prospective assessments, case control and case series studies were included.

RESULTS

741 studies were found. Of those, 18 were duplicated and 77 were not related to urology procedures. Of the remaining 646 studies, 59 were considered of relevance and selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. Operative time was in average 20% shorter with digital scopes, single-use or not. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Longer scope longevity is achieved with Cidex and if a dedicated nurse takes care of the sterilization process. The main surgical factors that negatively impact device longevity are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. We have built a comprehensive fi nancial costeffective decision model to fl exible ureteroscope acquisition.

CONCLUSIONS

The cost-effectiveness of a fl exible ureteroscopy program is dependent of several aspects. We have developed a equation to allow a literature-based and adaptable decision model to every interested stakeholder. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls.

A clinical evaluation of the new digital single-use flexible ureteroscope (UscopePU3022): an international prospective multicentered study

Introduction

We assessed the clinical performance of a new digital single-use flexible ureteroscope (UscopePU3022).

Material and methods

A prospective cohort study was carried out across 11 centers (July-Oct. 2017). The UscopePU3022 was assessed regarding ease of insertion; deflection, image quality, maneuverability and overall performance using either a visual analog* or Likert scale.

Results

A total of 56 procedures were performed in 11 centers (16 surgeons) with the indication being renal stones in 83%. The median score for ease of scope insertion was 10 (3-10). Intraoperative maneuverability was rated as 'good' in 38% and 'very good' in 52%. Visual quality was rated as 'poor or bad' in 18%, 'fair' in 37% and 'good or very good' in 43%. Two scopes failed intraoperatively (4%). Preoperative and postoperative median upward and downward deflection was 270 degrees. Compared to standard flexible ureteroscopy (f-URS) maneuverability was rated as 'equivalent' in 30% and 'better' in 60%; visual quality was 'worse' in 38% and 'equivalent or better' in 62%; limb fatigue scores were 'better' in 86%; and overall performance was 'worse' in 55% and 'equivalent or better' in 45%.

Conclusions

UscopeTM3022 performed well with regards to maneuverability, deflection and limb fatigue and appears to be at least non-inferior to standard f-URS with regards to these parameters. Poor image quality is a concern for UscopePU3022 with it receiving a low overall performance rating when compared to standard f-URS. Despite this it scored highly when investigators were asked if they would use it in their practice if it was cost-effective to do so.

Flexible ureteroscopic holmium laser lithotripsy with PolyScope for senile patients with renal calculi

The present study reported the clinical experience of using a PolyScope with holmium laser lithotripter in managing renal calculi in senile patients. Between December 2013 and December 2016, 157 senile patients (69.1±6.1 years old) were treated with PolyScope holmium laser lithotripsy for renal calculi at Xin Hua Hospital (Shanghai, China). The mean stone digitized surface area was 154.2±57.7 mm² (range, 55.8–478.3 mm²). A thorough medical history investigation, and laboratory and radiological examination were followed by proper preoperative management. The PolyScope was then passed into the renal cavities following the position of the ureteral access sheath, with laser energy maintained at 1.0–2.0 J, frequency 10–15 Hz. The demographical and operative information of senile patients were compared with that of the 332 non-senile patients operated at the same period time. The average operative time was 54.6±13.2 min (range, 37–124 min). No major complications, including ureteral perforation or sepsis were encountered. The single session stone-free rate (SFR) was 81.5% and the overall SFR was 89.2%, similar to that of the non-senile group. PolyScope combined with holmium laser lithotripter is safe and effective in managing renal calculi in senile patients compared with non-senile patients, with considerately high SFRs and low complication rates.

Single use and disposable flexible ureteroscopes

PURPOSE OF REVIEW

Flexible ureteroscopy has been widely developed in the last decade been nowadays one of the first line treatment options for urolithiasis and conservative management for upper tract urothelial tumors. Even though some unfavorable features of the reusable flexible scopes can limit the surgical procedure such as their availability, lack of sterilization or costly repairs. Disposable scopes have been developed with the intention of improving such problems.

RECENT FINDINGS

To our knowledge, seven devices have been developed. Of the scopes features, size, deflection, image quality and ergonomic handling have to be at least as good as reusable ones as they are expected to be noninferior. Three devices match all the features of reusable scopes, although only one has been properly studied.

SUMMARY

Not all the available disposable devices have been properly studied or compared with standard scopes. Although some devices are promising more studies are needed to proof their benefits.

Retrograde intrarenal surgery using the single - use flexible ureteroscope Uscope 3022 (Pusen™): evaluation of clinical results

Introduction

Reusable endoscopes have some limitations regarding their continued use. To sort out these problems, several disposable devices have appeared on the market. Our objective is to show our clinical results with a new digital flexible single-use ureteroscope.

Materials and methods

This study presents a prospective series of patients who underwent endoscopic surgery as treatment for renal stones using the digital disposable endoscope Uscope 3022™. Demographic, procedure and stone information were registered including surgery time, stone-free rate, need of ureteral catheterization and complications, among others. The behavior of the ureteroscope in terms of image quality and problems associated with flexibility and the working channel were also registered.

Results

A total of 71 procedures were included in the analysis. The mean age was 49.9 years old, with 70.4% of male patients. Mean stone size was 11.4 mm (4 to 40 mm). The most frequent stone location was in the lower calyces (28.2%). The stone burden was high (>2 cm) in 8.4% of patients. The mean surgical time was 56.6 minutes (15–180 min). In 94.4% of the cases, a laser was used with dusting parameters. The global stone-free rate (SFR) was 95.2%, but in the subgroups analysis SFR were significantly superior in stones less than 10 mm (97.9%) versus stones between 10 and 20 mm (94.5%) and greater than 20 mm (78.3%) (p <0.01). The postoperative placement of double-J stents was required in 66.2% of patients. Two minor complications were recorded and they were related to the ureteral access sheath used. There were no problems regarding the performance of the ureteroscope.

Conclusions

The clinical data observed in this series does not differ from the results traditionally obtained with other reusable devices. To our knowledge, this series is the first worldwide report evaluating the clinical behavior and results in humans of the Uscope 3022.

Single-use flexible ureteropyeloscopy: a systematic review

PURPOSE

Data assessing the effectiveness of single-use flexible ureteropyeloscopy (FURS) are limited. This study evaluates and compares single-use FURS with conventional reusable FURS.

METHODS

A systematic search using electronic databases (Pubmed and Embase) was performed for studies evaluating single-use FURS in the setting of urinary tract stone disease. Outcome measures included a comparative evaluation of their mechanical, optical and clinical outcomes.

RESULTS

Eleven studies on 466 patients met inclusion criteria. In vitro comparative data were available on three single-use flexible ureteropyeloscopes (LithoVue™, Polyscope™ and SemiFlex™) and clinical data were available on two (LithoVue™ and Polyscope™). The overall stone-free rate and complication rate associated with single-use FURS was 87 ± 15% and 9.3 ± 9%, respectively. There were no significant differences in procedure duration, stone size, stone clearance and complication rates when single-use FURS and reusable FURS were compared (duration: 73 ± 27 versus 74 ± 13 min, p = 0.99; stone size: 1.36 ± 0.2 versus 1.34 ± 0.18 cm, p = 0.93; stone-free rate: 77.8 ± 18 versus 68.5 ± 33%, p = 0.76; complication rate 15.3 ± 10.6 versus 15 ± 1.6%, p = 0.3).

CONCLUSIONS

Single-use FURS demonstrates comparable efficacy with reusable FURS in treating renal calculi. Further studies on clinical efficacy and cost are needed to determine whether single-use FURS will reliably replace its reusable counterpart.

Contract Costs Associated with Maintaining Flexible Ureteroscopes: A Single Center Experience

INTRODUCTION

We compared the cost of flexible ureteroscope processing and maintenance contracts offered by a scope manufacturer and a third-party company.

METHODS

Use and repairs of the Storz 11278AU1 Flex X2 Flexible Ureteroscope are prospectively recorded at our large, 371-bed, acute care hospital. A retrospective analysis of the processing of ureteroscopic instruments during a 3-year period (2011 to 2013) was completed. We compared the handling of ureteroscopes between 1 year under a third-party contractor (Integrated Medical Systems International, Inc. [IMS]) and 2 prior years under the manufacturer (KARL STORZ) contract.

RESULTS

From January 1, 2011 through October 1, 2012 our institution used the manufacturer for the processing of ureteroscopic instruments. From January 1, 2013 through December 9, 2013 our institution used the third-party contractor IMS for repairs. The number of procedures performed per repair/exchange during the manufacturer contract was 19.9 and the number of procedures performed per repair/exchange during the third-party contract was 11. The third-party contract resulted in a reduction of procedures performed per repair/exchange by 52%. Adjusted for inflation, the yearly cost of ureteroscope repairs was $125,715 during the manufacturer contract and $158,040 during the third-party contract. By analyzing the costs incurred in 2013, if our institution had maintained the manufacturer contract for all 3 years, the estimated repair cost would have resulted in a savings of $32,325.

CONCLUSIONS

Using the manufacturer repair contract is more cost-effective than using that of third-party companies.

Retrograde intrarenal surgery for renal stones - Part 1

The main aim in the treatment of renal stones is to clearance of the stones completely with the least morbidity. Parallel to the improvements in technology during recent years, new flexible ureterorenoscopes and effective lithotripters such as holmium laser have been developed, thus retrograde intrarenal surgery (RIRS) has become an efficient and safe option in the management of urinary system stone disease with a gradually increasing popularity. Therewithal, innovations in auxiliary equipment such as guide-wires, ureteral access sheath and stone baskets have made this procedure more effective. With this modality, nowadays, the vast majority of renal stones can be treated successfully without need of open surgery or percutaneous nephrolithotomy. RIRS can be used as a primary treatment in patients with renal stones smaller than 2 cm, in cases with prior unsuccessful shock wave lithotripsy (SWL), infundibular stenosis, renoureteral malformation, musculoskeletal deformity, bleeding diathesis as well as obese patients. The efficiency of this procedure has been also proved in pediatric patients. In the first part of this detailed review for RIRS, history, indications and contraindications, preoperative preparation, antibiotic prophylaxis, anesthesia, surgical technique related to flexible ureteroscopes and auxiliary equipment being used, postoperative care and complications of this operation are discussed with up-to-date literature.

Evaluation of a Novel Single-Use Flexible Ureteroscope

Introduction: A novel single-use flexible ureteroscope promises the optical characteristics and maneuverability of a reusable fourth-generation flexible ureteroscope. In this study, the LithoVue Single-Use Digital flexible ureteroscope was directly compared with contemporary reusable flexible ureteroscopes, with regard to optics, deflection, and irrigation flow. Methods: Three flexible ureteroscopes such as the LithoVue (Single Use; Boston Scientific), Flex-Xc (Karl Storz, Germany), and Cobra (Richard Wolf, Germany) were assessed in vitro for image resolution, distortion, color representation, grayscale imaging, field of view, and depth of field. Ureteroscope deflection was tested with an empty channel followed by placement of a 200 μm laser fiber and a 1.9F wire basket, a 2.0F nanoelectric pulse lithotripsy (NPL) probe, and a 2.4F NPL probe. Ureteroscope irrigation flow was measured using normal saline at 100 cm, with an empty channel followed by a 200 μm laser fiber, a 1.9F wire basket and a 2.0F NPL probe. Results: The LithoVue showed the largest field of view, with excellent resolution, image distortion, and depth of field. No substantial difference was demonstrated in color reproducibility or in the discernment of grayscales between ureteroscopes. The LithoVue maintained full deflection ability with all instruments in the working channel, although the Flex-Xc and Cobra ureteroscopes showed loss of deflection ranging from 2° to 27°, depending on the instrument placed. With an empty channel, the LithoVue showed an absolute flow rate similar to the Flex-Xc ureteroscope (p = 0.003). It maintained better flow with instruments in the channel than the Flex-Xc ureteroscope. The Cobra ureteroscope has a separate 3.3F instrument channel, keeping flow rates the same with instrument insertion. Conclusion: The LithoVue Single-Use Digital ureteroscope has comparable optical capabilities, deflection, and flow, making it a viable alternative to standard reusable fourth-generation flexible digital and fiberoptic ureteroscopes.

Comparison of New Single-Use Digital Flexible Ureteroscope Versus Nondisposable Fiber Optic and Digital Ureteroscope in a Cadaveric Model

Purpose: To evaluate LithoVue, the new single-use digital flexible ureteroscope, in a human cadaveric model and compare it with a nondisposable fiber optic and digital flexible ureteroscopes.

Materials and Methods: LithoVue, a conventional fiber optic, and digital flexible ureteroscopes were each tested in four renal units of recently deceased female cadavers by three surgeons. The following parameters were analyzed: accessibility to the kidney and navigation of the entire collecting system with and without ureteral access sheath (UAS), lower pole access measuring the deflection of the ureteroscope with the working channel empty, and with inside two different baskets and laser fibers. A subjective evaluation of maneuverability and visibility was assessed by each surgeon at the end of every procedure.

Results: Kidney access into the Renal unit 1 was not possible without UAS for all ureteroscopes because of noncompliant ureter at the level of sacroiliac joint. The reusable digital ureteroscope was unable to reach one calix of the lower pole and one calix of the upper pole (Renal units 2 and 3) without UAS placement. Lower pole access with baskets and laser fibers was possible for each ureteroscope after UAS placement. No statistically significant differences were detected in angle deflection between ureteroscopes. The digital ureteroscope was preferred for visibility in all procedures: LithoVue for maneuverability in six procedures, fiber optic in five procedures, and the digital ureteroscope in one procedure.

Conclusions: LithoVue seems to be comparable with conventional ureteroscopes in terms of visibility and manipulation into the collecting system in fresh human cadavers. Further studies in humans are needed to determine the clinical value of this new instrument.

Modular flexible ureteroscopy and holmium laser lithotripsy for the treatment of renal and proximal ureteral calculi: A single-surgeon experience of 382 cases

To determine the safety and efficacy of modular flexible ureteroscopy and holmium laser lithotripsy for the treatment of renal and proximal ureteral calculi, a retrospective chart review of a single surgeon's 3-year modular flexible ureteroscopy experience was performed. All of the patients were treated with modular flexible ureteroscopy and holmium laser lithotripsy by a single surgeon. Stone-free status was defined as no fragments or a single fragment ≤4 mm in diameter at the 3-month follow-up. The procedure number, operative time, stone-free rates, repeat usage of the multilumen catheter, and perioperative complications were documented. The present study included 215 male patients and 167 female patients, with an average age of 48.5±13.7 years (range, 17-84 years). The mean stone size was 11.5±4.1 mm (range, 4-28 mm), and the mean total stone burden was 17.5±5.7 mm (range 15-46 mm). A total of 305 patients (79.8%) had a stone burden ≤20 mm, and 77 patients (20.2%) had a stone burden >20 mm. The mean number of primary procedures was 1.3±0.2 (range, 1-3). The stone-free rate following the first and the second procedure was 73.4 and 86.9%, respectively. The mean postoperative hospital stay was 3.1±1.2 days (range, 2-6 days). The highest clearance rates were observed for proximal ureteral stones (100%) and renal pelvic stones (88.7%), whereas the lowest clearance rates were observed for lower calyx stones (76.7%) and multiple calyx stones (77.8%). The higher the initial stone burden, the lower the postoperative stone-free rate (≤20 vs. >20 mm; 89.8 vs. 75.3%). The overall complication rate was 8.1%. The results of the present study suggest that modular flexible ureteroscopy with holmium laser lithotripsy may be considered the primary method for the treatment of renal and proximal ureteral calculi in select patients, due to its acceptable efficacy, low morbidity, and relatively low maintenance costs.

Risk factors of infectious complications following flexible ureteroscope with a holmium laser: a retrospective study

PURPOSE

We aimed to evaluate the effectiveness of flexible ureteroscope for treating kidney stones and the risk factors for infectious complications following flexible ureteroscope (FURS) with a holmium laser.

METHODS

We retrospectively reviewed the data of 227 patients with kidney stones who underwent flexible ureteroscope with a holmium laser at our hospital from January 2012 to September 2014, including gender, age, comorbidity, urine analysis results, urine culture results, blood test results, stone size, operative duration, and residual stones. Patients with and without infectious complications were assigned to groups A and B, respectively. The dependent variables were postoperative infectious complications, and the risk factors for infectious complications following FURS were assessed using Chi-square tests and multivariate logistic regression analyses.

RESULTS

All the surgeries were successfully completed. The total stone-free rate was 81.9% (n = 186), and the incidence of infectious complications after FURS was 8.37% (n = 19). Fifteen patients (6.61%) developed fever postoperatively, 10 patients (4.41%) developed systemic inflammatory response syndrome (SIRS), 6 patients with fever were considered to have SIRS (2.64%), and 2 patients had sepsis (0.88%). Univariate analyses of groups A and B indicated that pyuria, stone size, operative duration, and infectious stones were risk factors for infectious complications after FURS (P < 0.05). Multivariate logistic regression analyses indicated that pyuria (P = 0.017), operative duration (P = 0.026), and infectious stones (P = 0.030) were independently related to infectious complications.

CONCLUSION

Pyuria, operative duration, and infectious stones were risk factors for infectious complications following FURS. Hence, routine urinalysis findings should be carefully considered, particularly the finding of pyuria.

Disposable devices for RIRS: where do we stand in 2013? What do we need in the future?

PURPOSE

Disposable devices for retrograde intrarenal surgery (RIRS) form a significant part of the urologist's armamentarium for the endoscopic management of urologic diseases. Herein, we provide an overview of the literature regarding the advances and controversies of these devices.

METHODS

A PubMed search was used to identify the literature discussing the subject of disposable devices for RIRS. Articles published between 2012 and 2013 were considered.

RESULTS

Ureteral access implements including access sheaths, wires, and dilators are an area of both improvement and controversy regarding their proper use. The safety, effectiveness, and limitations of lithotrites continue to be refined. Stone retrieval devices are undergoing persistent miniaturization, and their use may prove to be cost effective. The debate over perioperative stenting remains, while symptom management is explored. A cost-effective option for disposable flexible ureteroscopy shows promise.

CONCLUSIONS

While rapid advances in technology and knowledge continue, continual improvements are necessary. Disposable equipment needs persistent refinement and possible miniaturization. More efficient fragment retrieval devices are needed. Durability of laser fibers and safety within ureteroscopes needs to be improved. Reducing stent morbidity remains an ongoing challenge. Lastly, costs need to be reduced by the further development of disposable flexible ureteroscopes and in the recyclability of disposable devices to improve availability worldwide.

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.