In vitro Comparison of the Mechanical and Optical Characteristics of 5 Disposable Flexible Ureteroscopes.

INTRODUCTION: Disposable (single-use) flexible ureteroscopes are alternatives to reusable ureteroscopes. With their superior surgical efficacy and safety in the presence of upper urinary calculi, disposable ureteroscopes aim to overcome the main limitations of conventional reusable ureteroscopes. However, studies on the performance of the most recently developed models of single-use flexible ureteroscopes are scarce. This study aimed to compare the in vitro performance of several recently introduced, single-use, flexible ureteroscopes. METHODS: Five disposable flexible ureteroscopes were tested in vitro to evaluate their mechanical and optical characteristics. To this end, their degrees of deflection, irrigation flow rates, and image qualities were investigated. The models examined were Innovex US31-B12, OTU-100RR, Redpine RP-U-C12, Sciavita SUV-2A-B, and Seplou URS3016E. Their performance was also compared with that of a reusable flexible ureteroscope, Olympus URV-F. RESULTS: The OTU device had the highest degrees of deflection and the smallest loop diameter of the disposable ureteroscopes. The single-use ureteroscopes had identical image resolutions at a distance of 1 cm. The Innovex and Redpine devices had the best color representation. CONCLUSIONS: Of the tested disposable ureteroscopes, the OTU device had the best mechanical attributes, given its small loop diameter, high deflection angles, and low irrigation flow loss. As to their optical properties, the resolutions of all 5 single-use models were identical at an image distance of 1 cm.

Single-Use Flexible Ureteroscopes: How Difficult Is It Today to Stay Up to Date? A Pictorial Review of Instruments Available in Europe in 2023.

The invention of the flexible ureteroscope (fURS) and its subsequent spread have revolutionized the surgical management of urolithiasis and upper tract urothelial carcinoma (UTUC). During the last few years, single-use flexible ureteroscopes (su-fURSs) have been developed to improve the limitations of reusable fURSs, namely their cost, durability and risk of device contamination. Since the introduction of the first fully disposable digital fURS, several su-fURSs have been developed by various manufacturers. In this pictorial review, we combined the different physical and technical features of su-fURSs currently available on the market with Food and Drug Administration (FDA) and European Conformity (CE) approval, in order to help surgeons choose the appropriate device according to each case requirement and personal preferences. To the best of our knowledge, 17 su-fURSs with CE and FDA approval have been developed to date.

Single-use flexible ureteroscopes: Comparative in vitro analysis of four scopes.

Objective: Single-use flexible ureteroscopes (fURSs) have recently been introduced by different companies. Goal of this in-vitro study was to compare four fURSs. Methods: We performed in vitro analysis of Uscope 7.5 Fr and Uscope 9.5 Fr (Pusen Ltd., Zhuhai, China), LithoVue 9.5 Fr (LithoVue™, Boston Scientific, MA, USA), and Indoscope 9.5 Fr (Bioradmedisys™, Pune, India). Optical characteristics (image resolution, color representation, and luminosity) were compared at various distances of 10 mm, 20 mm, and 50 mm. Deflection and irrigation were evaluated with and without accessories. Results: Color perception was comparable for all scopes at 10 mm (p<0.05), while Lithovue 9.5 Fr was comparable with Indoscope 9.5 Fr at the distances of 20 mm and 50 mm. Both scopes were statistically better than both Uscopes at the distances of 20 mm and 50 mm. Image resolution powers were comparable amongst all fURSs at the distances of 10 mm and 20 mm (3.56 line pairs per millimeter [lp/mm]). However, Indoscope (3.56 lp/mm) was superior to LithoVue and Uscope scopes (3.17 lp/mm) at the distance of 50 mm. Luminosity at the distance of 10 mm was comparable for LithoVue and Uscope 9.5 Fr. However, at the distances of 20 mm and 50 mm, LithoVue had the highest luminosity while Uscope 7.5 Fr had the lowest one. Indoscope had lower luminosity than other 9.5 Fr scopes at all distances. With empty working channel and 200 µm laser fiber, Indoscope had the maximum deflection (285°). With basket, Uscope 7.5 Fr had the maximum loss of deflection (30°) while Indoscope had no deflection loss. With empty working channel, all scopes had comparable irrigation flow rates in both deflected and undeflected state. Similarly, with 200 µm laser or basket, irrigation flow rates were comparable in all scopes. Conclusion: Color representation was equivalent for Indoscope and LithoVue, while being better than Uscope 7.5 Fr and Uscope 9.5 Fr. Image resolution was comparable in all scopes at the distances of 10 mm and 20 mm. Beyond the distance of 10 mm, luminosity of LithoVue was the highest and that of Uscope 7.5 Fr was the lowest. Deflection loss was the minimum with Indoscope and the maximum with 7.5 Fr Uscope. Under all scenarios, irrigation flow rates were comparable in all scopes.

Comparison of Flexible Ureteroscope Performance between Reusable and Single-Use Models.

BACKGROUND: Single-use flexible ureteroscopes for urinary retention have been developed in recent years as an alternative to reusable ureteroscopes in order to eliminate the risk of cross-infections and to solve the primary limitations of traditional reusable flexible ureteroscopes for urinary retention. METHODS: In this study, we evaluated and contrasted three of the most recent types of flexible ureteroscopes, including two digital reusable versions (Olympus URF-V and Olympus URF-V2) and one single-use model (Pusen Medi-calUscope UE3022), in both ex vivo and in vivo scenarios. The influence of a variety of instruments on the flow of irrigation and its deflection was investigated ex vivo. In the in vivo investigation, a total of 40 patients were treated with retrograde fURS utilizing URF-V, 20 patients were treated with URF-V2, and 20 patients were treated with single-use fURS. The visibility and maneuverability of each fURS were evaluated by the same urologist during the procedures, and the results were compared. RESULTS: Intraoperatively, we compared the image quality of reusable (URF-V and URF-V2) and single-use fURS USCOPE UE3022 cameras and found that there was no statistically significant difference between the two types of camera. The score for maneuverability was the same (4.2) regardless of whether we used the UscopeUE3022 or the URF-V2, but it was significantly lower (3.8, p = 0.03) when we utilized the URF-V. Irrigation was about the same when utilizing reused scopes, whereas employing a single-use scope was more than fifty percent more effective. CONCLUSIONS: The findings of our research indicate that reusable and single-use fURs have visibility and maneuverability characteristics that are at least comparable to one another. The possibilities of the single-use type in terms of irrigation flow and deflection are superior.

Comparison of Surgical Outcomes between Single-Use and Reusable Flexible Ureteroscopes for Renal Stone Management: A Systematic Review and Meta-Analysis.

Background and Objectives: Disposable flexible ureteroscopes have been widely used because of their cost-effectiveness and higher sterility potential compared with reusable flexible ureteroscopes. This study aimed to compare the surgical outcomes and complication rates in patients who undergo reusable or disposable flexible ureteroscopic stone surgeries (fURS) for urinary stone disease. Materials and Methods: A systematic review and meta-analysis were conducted under the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. This systematic review was registered with PROSPERO (CRD42022331291). Clinical trials comparing reusable and disposable fURS for stone disease were found from PubMed, EMBASE, Cochrane Library, and the Web of Science up to March 2022. Participants were patients with upper urinary tract stones; the interventions were reusable or disposable fURS. Outcomes, including stone-free rate, operation time, length of hospital stay, and complication rate, were compared for analysis. Results: Overall, 111 studies were identified, but after removing duplicate studies, 75 studies remained. Thirty-two of these studies were excluded. Of the 43 screened studies, 11 met the eligibility criteria. There was no difference in the stone-free rate (SFR) between disposable and reusable fURS (p = 0.14; OR = 1.36; 95% CI, 0.9 to 2.04). For operation time, no difference was identified between reusable and disposable fURS groups (p = 0.12; MD = -5.31; 95% CI, -12.08 to 1.46). For hospital stay, there was also no difference between the two groups (p = 0.61; MD = -0.03; 95% CI, -0.17 to 0.10). There was no significant difference in complication rate between the two groups (p = 0.85; OR = 0.95; 95% CI, 0.56 to 1.61). Conclusions: There were no differences in the SFR, operation time, length of hospital stay, and complication rate between reusable and disposable fURS. Disposable fURS may be a comparable alternative to reusable fURS.

Pattern Analysis of Laser Fiber Degradation According to the Laser Setting: In Vitro Study of the Double-Firing Phenomenon.

BACKGROUND: It is essential to understand the mechanism of the various causes of laser fiber damage and an ideal method of reducing endoscope damage induced by laser emission in multiple sites. This study classified the different patterns of laser fiber degradation according to laser settings and analyzed the role of cavitation bubbles to find a desirable way of minimizing endoscope damage. METHODS: A total of 118 laser fibers were analyzed after 1-,3-, and 5-min laser emission to artificial stones under the settings of 1 J-10 Hz, 1 J-20 Hz, 1 J-30 Hz, and 2 J-10 Hz. Every 3 cm from the fiber tip was marked and examined with a digital microscope and a high-speed camera. The images of the fibers and the movement of cavitation bubbles were taken with a distance of 1 to 5 mm from the gel. RESULTS: Seven types of fiber damage (charring, limited and extensive peeled-off, bumpy, whitish plaque, crack, and break-off) coincided during laser emission. Damages rapidly increased with emission time > 3 minutes regardless of the laser settings. The damaged lengths covered 5 mm on average, and the fibers at 5-min emission were significantly shorter than others. The fiber durability of 1J-10Hz setting was better than other settings after 3-min laser emission. Backward movement of the cavitation bubbles was found at the 1-mm distance from the gel, and the damaged lengths were longer than the diameters of the cavitation bubbles because of their proximal movement. CONCLUSION: The damage patterns of the laser fiber tips were classified into seven types. The heat damage around the surface of the laser fiber can be increased according to the high-energy or high-frequency laser setting, a short distance to the stone, a short distance from the tips of flexible ureteroscopes, no cutting laser fiber procedures, and the inappropriate use of irrigation fluid or laser fiber jacket.

An outbreak of postoperative rapidly developing and multidrug-resistant Klebsiella pneumoniae urosepsis due to a contaminated ureteroscope.

INTRODUCTION: Outbreaks caused by microorganisms contaminating the inside of rigid ureteroscopes are extremely rare. Some of these outbreaks, especially those caused by multidrug-resistant (MDR) infections, can cause serious problems, even death. Among these serious infections, we have no data about Klebsiellapneumoniae outbreaks caused by rigid ureteroscopes and their management and consequences.

Single-use flexible ureteroscopes: update and perspective in developing countries. A narrative review

ABSTRACT Flexible ureteroscopy is a well-established method for treatment of urinary stones but flexible ureteroscopes are expensive and fragile devices with a very limited lifetime. Since 2006 with the advent of digital flexible ureteroscopes a great evolution has occurred. The first single-use flexible ureteroscope was launched in 2011 and new models are coming to the market. The aim of this article is to review the characteristics of these devices, compare their results with the reusable devices and evaluate the cost-benefits of adopting single-use flexible ureteroscopes in developing countries. Materials and Methods: an extensive review of articles listed at PubMed and published between 2000 and 2021 was performed. Results: Single-use flexible ureteroscopes have a shaft with 65 to 68cm length and weight between 119 and 277g. Their deflection goes up to 300 degrees. Their stone-free rates vary between 60 and 95% which is comparable to reusable scopes and operative times ranges from 54 to 86 minutes which are lower when compared to reusable flexible scopes. Their costs vary between 800 and 3180 US dollars. Conclusion: single-use flexible ureteroscopes are lighter and have superior quality of image when compared to fiberoptic ones. There are no definite data showing a higher stone-free rate or less complications with the use of single-use flexible ureteroscopes. Each institution must perform a cost-benefit analysis before making the decision of adopting or not such devices depending on the local circumstances.

Prospective, Randomized Comparison of Dual-Lumen vs Single-Lumen Flexible Ureteroscopes in Proximal Ureteral and Renal Stone Management.

Introduction: We sought to compare the safety, efficacy, efficiency, and surgeon experience during upper urinary tract stone management with single-lumen (SLFU) vs dual-lumen flexible ureteroscopes (DLFU). Materials and Methods: Seventy-nine patients with proximal ureteral or renal stone burden <2 cm were randomized to a SLFU or DLFU. We recorded times for ureteroscopy (URS), laser lithotripsy, stone basketing, as well as intraoperative and postoperative complications. The rate of stone clearance and stone free status were calculated using CT imaging. Surgeons completed a survey after each procedure rating various metrics regarding ureteroscope performance. Results: Thirty-five patients from the single-lumen group and 44 patients from the dual-lumen group had comparable median URS time (37 vs 35 minutes, p = 0.984) and basketing time (12 vs 19 minutes; p = 0.584). Median lithotripsy time was decreased in the dual-lumen group (single: 6 vs dual: 2 minutes, p = 0.017). The stone clearance rate was superior in the dual-lumen group (single: 3.7 vs dual: 7.1 mm3/min, p = 0.025). The absolute stone-free rate (SFR) was superior for the dual-lumen group (single: 26% vs dual: 48%, p = 0.045). No differences in intraoperative (single: 0% vs dual: 2%; p = 0.375) and postoperative complications (single: 7% vs dual: 11%, p = 0.474) were observed. Surgeons' ratings of the dual-lumen ureteroscope was superior for visibility, comfort, ease of use, and overall performance. Conclusions: The use of the dual-lumen ureteroscope in patients with renal and proximal ureteral stones <2 cm provided shorter lithotripsy time, higher stone clearance rates, improved SFR, and superior surgeon ratings when compared with SLFUs.

Repair Rate and Associated Costs of Reusable Flexible Ureteroscopes: A Systematic Review and Meta-analysis.

CONTEXT: The refined mechanics of a flexible ureteroscope (fURS) are vulnerable to damage. Sending the fURS for repair is costly and has driven interest toward estimating the resources used for fURS repairs. OBJECTIVE: To systematically review available literature and to estimate the total weighted repair rate of an fURS and the average repair cost per ureteroscopy. EVIDENCE ACQUISITION: A systematic review was conducted by searching the MEDLINE, Embase, Web of Science, and Cochrane Library databases. The average costs of all repairs identified in the included studies were extracted. A random-effect model was used to calculate the pooled total fURS repair rate. The total weighted repair rate and average cost per repair were multiplied to provide an average cost of repair per ureteroscopy procedure. EVIDENCE SYNTHESIS: We identified 18 studies that fulfilled the inclusion criteria, which included 411 repairs from 5900 investigated ureteroscopy procedures. The calculated weighted repair rate was 6.5% ± 0.745% (95% confidence interval: 5.0-7.9%; I2 = 75.3%), equivalent to 15 ureteroscopy procedures before repair. The average cost per repair was 6808 USD; according to the weighted repair rate of 6.5%, this corresponds to an average repair cost of 441 USD per procedure. Egger's regression test did not reveal a significant publication bias (p = 0.07). CONCLUSIONS: This is the first meta-analysis to estimate the repair rate of the fURS used for ureteroscopy. Our analysis demonstrates a repair rate of 6.5%, equivalent to 15 ureteroscopy procedures between fURS repairs and a repair cost of 441 USD per procedure. Ureteroscopy practices should consider fURS breakage rates and repair costs to optimize the use of reusable versus disposable devices. PATIENT SUMMARY: We reviewed available literature investigating the repair rate of a flexible ureteroscope (fURS). We found that fURSs are sent for repair after every 15 ureteroscopy procedures, corresponding to 441 USD per procedure in repair cost.

Single-use flexible ureteroscopes: update and perspective in developing countries. A narrative review.

Flexible ureteroscopy is a well-established method for treatment of urinary stones but flexible ureteroscopes are expensive and fragile devices with a very limited lifetime. Since 2006 with the advent of digital flexible ureteroscopes a great evolution has occurred. The first single-use flexible ureteroscope was launched in 2011 and new models are coming to the market. The aim of this article is to review the characteristics of these devices, compare their results with the reusable devices and evaluate the cost-benefits of adopting single-use flexible ureteroscopes in developing countries. MATERIALS AND METHODS: an extensive review of articles listed at PubMed and published between 2000 and 2021 was performed. RESULTS: Single-use flexible ureteroscopes have a shaft with 65 to 68cm length and weight between 119 and 277g. Their deflection goes up to 300 degrees. Their stone-free rates vary between 60 and 95% which is comparable to reusable scopes and operative times ranges from 54 to 86 minutes which are lower when compared to reusable flexible scopes. Their costs vary between 800 and 3180 US dollars. CONCLUSION: single-use flexible ureteroscopes are lighter and have superior quality of image when compared to fiberoptic ones. There are no definite data showing a higher stone-free rate or less complications with the use of single-use flexible ureteroscopes. Each institution must perform a cost-benefit analysis before making the decision of adopting or not such devices depending on the local circumstances.

Comparison of pre- and post-surgical images of reusable and single use flexible ureteroscopes: a qualitative analysis.

INTRODUCTION: Given the fragility of reusable ureterorenoscopes, many single use instruments have appeared on the market. Unfortunately, reuse of these scopes occurs in undeveloped countries in order to cut costs. This raises safety concerns for the patient.The aim of this article was to macroscopically evaluate the changes that single use flexible ureterorenoscopes (su-fURS) suffer after a retrograde intrarenal surgery (RIRS), and to compare them to reusable fURS. MATERIAL AND METHODS: Pre and post-operative images of the instruments used in 23 RIRS were obtained. All the cases had renal calculi of the inferior calix between 10-15 mm, and all of them were treated with Holmium laser. The ureterorenoscopes used were: Storz® Flex X2, Storz® Flex XC, Pusen® 3022, OTU® Wiscope, AnQIng® Innovex and Boston Scientific® LithoVue. Qualitative comparisons of these were made. RESULTS: After su-fURS usage, significant damage was observed, especially on the distal tip. Deflection was not compromised. Reusable fURS did not sustain any damage after their use. CONCLUSIONS: fURS are delicate equipment, especially if they are of single use. The considerable damage sustained by single use scopes could mean that reuse of these instruments is dangerous and should be avoided.

Relevance of Adopting a Hybrid Strategy Mixing Single-Use and Reusable Ureteroscopes for Stones Management: An Economic Study to Support the Best Strategy.

Endoscopic procedures such as ureteroscopy (URS) have seen a recent increase in single-use devices. Despite all the advantages provided by disposable ureteroscopes (sURSs), their cost effectiveness remains questionable, leading most teams to use a hybrid strategy combining reusable (rURS) and disposable devices. Our study aimed to create an economic model that estimated the cut-off value of rURS procedures needed to support the profitability of a hybrid strategy (HS) for ureteroscopy. We used a budget impact analysis (BIA) model that estimated the financial impact of an HS compared to 100% sURS use. The model included hospital volume, sterilization costs and the private or public status of the institution. Although the hybrid strategy generally remains the best economic and clinical option, a predictive BIA model is recommended for the decision-making. We found that the minimal optimal proportion of rURS procedures in an HS was mainly impacted by the activity volume and overall number of sterilization procedures. Private and public institutions must consider these variables and models in order to adapt their HS and remain profitable.

Current Disposable Ureteroscopes: Performance and Limitations in a Standardized Kidney Model.

Objectives: Due to the increasing fragility of the instruments and rising concerns about the sterility of reprocessable scopes, several single-use devices for flexible ureteroscopy have been introduced. In this study, we compare currently available disposable digital and fiberoptic flexible ureteroscopes with a contemporary reusable fiberoptic device. Materials and Methods: LithoVue™, Pusen Uscope® (UE3011, UE3022), Flexor®Vue™, and a reusable fiber optic flexible ureteroscope (BOA vision®) were tested in kidney models. The setup included (1) visualization of all calices (correct assignment of colored pearls) and (2) the extraction of human calculi with a standard disposable extraction device (NGage®). We documented the effective visualization, stone extraction, and times to completion. In addition, the surgeons' workload and performance were determined using the National Aeronautics and Space Administration-Task Load Index. Results: In visualizing and identifying calices, the LithoVue and both generations of the Uscope performed similarly, but time to completion was significantly longer for all single-use devices in comparison with the Boa Vision. LithoVue retracted stones almost as well as the reusable scope (97% vs 95%/82%/96% stone clearance), while accessibility was impeded using Uscope UE3011, as reflected by the retrieval time per stone (73 vs 102 seconds/stone). This disadvantage has, however, been overcome with the new Uscope Generation UE3022, showing a retrieval time of only 65 seconds per stone, excelling over the reusable scope in this category. The Uscope UE3022 image quality was also rated best, but showed no significant difference. Conclusions: In comparison with disposable ureteroscopes available, LithoVue offers performance and characteristics similar to a reusable device, while the FlexorVu's performance does not yet yield satisfactory results for clinical use. The first generation of Uscope exhibits potential, but requires further technical improvements to match the performance of a reusable device. With the new-generation UE3022, Pusen has made significant improvement and offers a quality comparable with the LithoVue's.

Does working channel position influence the effectiveness of flexible ureteroscopy? Results from an in vitro study.

OBJECTIVE: To evaluate whether the position of the working channel affects the effectiveness of flexible ureteroscopy. MATERIALS AND METHODS: We compared the ureteroscopes Flex-X2S and Flex-XC (working channel at the 9 and 3 o'clock positions, respectively) in eight cavities of a K-Box model, simulating the distribution of the right and left intrarenal calyces. In the first and second settings, each cavity contained a 1-cm stone, lying on the bottom and fixed on the anterior sheet covering the box, respectively. In the third setting, the posterior and lateral surface of each cavity was draped with graph paper. Once the flexible ureteroscope entered each cavity, we measured and compared (i) the proportion of stone surface targeted by the laser (STL) and (ii) the proportion of graph paper burned by the laser (PBL) obtained with the two instruments. RESULTS: Higher STLs and PBLs were obtained with the 3 o'clock position than the 9 o'clock position in the right posterior and left anterior cavities (mean ± sd STL 87% ± 15% vs 46% ± 38% and 78% ± 35% vs 43% ± 24%, respectively; P < 0.05), and on the right posterior surfaces of the middle-lower/lower cavities (PBL 72% vs 31% and 77% vs 35%, respectively; P < 0.01) and on the left lateral surface of the lower cavities (PBL 45% vs 25%; P = 0048), respectively. Conversely, the 9 o'clock position provided higher STLs and PBLs than the 3 o'clock position in the left posterior and right anterior cavities (mean ± sd STL 84% ± 20% vs 65% ± 28% and 79% ± 30% vs 44% ± 35%, respectively; P ≤ 0.02), and on the left posterior and right lateral surfaces of the lower cavities (PBL 59% vs 34% and 50% vs 21%, respectively; P ≤ 0.04). CONCLUSIONS: The position of the working channel of the flexible ureteroscope should be considered when planning flexible ureteroscopy, especially when dealing with the lower pole.

Characteristics of current digital single-use flexible ureteroscopes versus their reusable counterparts: an in-vitro comparative analysis.

BACKGROUND: Single-use flexible ureterorenoscopes (fURSs) have been recently introduced aiming to offer solutions to the sterilization, fragility and cost issues of the reusable fURSs. In order to be a viable alternative, the single-use scopes must prove similar capabilities when compared to their reusable counterparts. The goal of our in-vitro study was to compare the current reusable and single-use digital fURSs regarding their deflection, irrigation and vision characteristics. METHODS: We compared in-vitro 4 single-use fURSs-LithoVue™ (Boston Scientific, Marlborough, Massachusetts, USA), Uscope™ (Zhuhai Pusen Medical Technology Co. Ltd., Zhuhai, Guangdong Province, China), NeoFlex™ (NeoScope Inc, San Jose, California, USA) and ShaoGang™ (YouCare Technology Co. Ltd., Wuhan, China) versus 4 reusable fURSs-FLEX-Xc (Karl Storz SE & Co KG, Tuttlingen, Germany), URF-V2 (Olympus, Shinjuku, Tokyo, Japan), COBRA vision and BOA vision (Richard Wolf GmbH, Knittlingen, Germany). Deflection and irrigation abilities were evaluated with different instruments inserted through the working channel: laser fibres (200/273/365 µm), retrieval baskets (1.5/1.9/2.2 Fr), guide wires [polytetrafluoroethylene (PTFE) 0.038 inch, nitinol 0.035 inch] and a biopsy forceps. A scoring system was designed to compare the deflection impairment. Saline at different heights (40/80 cm) was used for irrigation. The flow was measured with the tip of the fURS initially straight and then fully deflected. The vision characteristics were evaluated (field of view, depth of field, image resolution, distortion and colour representation) using specific target models. RESULTS: Overall, the single-use fURSs had superior in-vitro deflection abilities than the reusable fURSs, in most settings. The highest score was achieved by NeoFlex™ and the lowest by ShaoGang™. PTFE guide wire had most impact on deflection for all fURSs. The 200 µm laser fibre had the lowest impact on deflection for the single-use fURSs. The 1.5 Fr basket caused the least deflection impairment on reusable fURSs. At the end of the tests, deflection loss was noted in most of the single-use fURSs, while none of the reusable fURSs presented deflection impairment. ShaoGang™ had the highest irrigation flow. Increasing the size of the instruments occupying the working channel led to decrease of irrigation flow in all fURSs. The impact of maximal deflection on irrigation flow was very low for all fURSs. When instruments were occupying the working channel, the single-use fURSs had slightly better in-vitro irrigation flow than the reusable fURSs. The field of view was comparable for all fURSs, with LithoVue™ showing a slight advantage. Depth of field and colour reproducibility were almost similar for all fURSs. ShaoGang™ and Uscope™ had the lowest resolution. FLEX Xc had the highest image distortion while LithoVue™ had the lowest. Partial field of view impairment was not for Uscope™ and ShaoGang™. CONCLUSIONS: In-vitro, there are differences in technical characteristics of fURSs. It appears that single-use fURSs deflect better than their reusable counterparts. Irrespective of deflection, the irrigation flow of the single-use fURSs was slightly superior to the flow of the reusable fURSs. Overall, reusable fURSs had better vision characteristics than single-use fURSs. Further in-vivo studies might be necessary to confirm these findings.

[Risk factors associated with systemic inflammatory response syndrome after flexible ueteroscopic lithotripsy based on enhanced recovery after surgery].

Objective: To investigate the risk factors of systemic inflammatory response syndrome (SIRS) in patients undergoing flexible ureteroscopic lithotripsy based on enhanced recovery after surgery (ERAS). Methods: The clinical data of 243 kidney stone cases who underwent flexible ureteroscopic lithotripsy based on ERAS in the First Affiliated Hospital of Wannan Medical College from January 2016 to December 2017 were analyzed retrospectively. The cases were divided into two groups according to whether they had SIRS after surgery: SIRS group (26 cases) and non-SIRS group (217 cases). The age, gender, laterality of kidney stone, history of previous kidney stone surgery, degree of hydronephrosis, multiple kidney stones, length of operation time, white blood cell count of preoperative urine routine, result of preoperative urine culture, use of preoperative antibiotics, diabetes and other chronic diseases in the groups were collected and analyzed. Results: SIRS occurred in 26 cases in this study, which accounted for 10.7% (26/243). Multivariate analysis found that, moderate and severe hydronephrosis (OR=6.711, P=0.008), stone burden ≥2 cm (OR=10.353, P<0.001), length of operation time ≥ 60 min (OR=5.583, P=0.011), white blood cell count of preoperative urine routine ≥25×10(6)/L (OR=6.195, P=0.005), positive preoperative urine culture (OR=4.216, P=0.011), diabetes and other chronic diseases (OR=4.532, P=0.006) were the independent risk factors for postoperative SIRS (P<0.05). Conclusions: The occurrence of SIRS after flexible ureteroscopic lithotripsy based on ERAS is closely correlated with hydronephrosis, stone burden, length of operation time, white blood cell count of preoperative urine routine, positive preoperative urine culture, diabetes and other chronic diseases.

Pre-Use Ureteroscope Contamination after High Level Disinfection: Reprocessing Effectiveness and the Relation with Cumulative Ureteroscope Use.

PURPOSE: We assessed the frequency of preoperative and persistent microbial contamination of flexible ureteroscopes after reprocessing and the relation of contamination to cumulative ureteroscope use. MATERIALS AND METHODS: We evaluated the effectiveness of high level disinfection with peracetic acid as well as data on ureteroscope use for 20 new flexible ureteroscopes from December 2015 to December 2017 at a single center. In the operating room pre-use and postuse microbial samples of the ureteroscope shaft and working channel were collected to evaluate microbial contamination after reprocessing. Positive cultures were defined as 30 cfu/ml or greater of skin flora, or 10 cfu/ml or greater of uropathogenic microorganisms. A generalized estimating equation model was used to analyze whether cumulative ureteroscope use was associated with positive pre-use cultures. RESULTS: Microbial samples were collected during 389 procedures. Pre-use ureteroscope cultures were positive in 47 of 389 procedures (12.1%), of which uropathogens were found in 9 of 389 (2.3%) and skin flora in 38 of 389 (9.8%). Urinary tract infection symptoms did not develop in any of the patients who underwent surgery with a uropathogen contaminated ureteroscope. In 1 case the pre-use culture contained the same bacteria type as the prior postuse culture. Cumulative ureteroscope use was not associated with a higher probability of positive cultures. CONCLUSIONS: Microbial contamination of reprocessed ureteroscopes was found in an eighth of all procedures. Notably uropathogenic microorganisms were discovered in a small proportion of all procedures. Persistent ureteroscope contamination with uropathogens was only rarely encountered. Cumulative ureteroscope use was not associated with a higher probability of microbial contamination.

Single-Use Flexible Ureteroscopes: How Do They Compare with Reusable Ureteroscopes?

Flexible ureteroscopy has become an important tool in the urologist's armamentarium. Until recently, reusable ureteroscopes were the only tools available to perform ureteroscopy. However, in recent years, single-use flexible and semirigid ureteroscopes have been developed as an alternative to reusable ureteroscopes. These disposable ureteroscopes were designed to mitigate problems associated with the use of reusable ureteroscopes, including the high costs related to ureteroscope acquisition, maintenance, processing, sterilization, and repairs. In this review, we provide an overview of currently available single-use flexible ureteroscopes, which include LithoVue, Uscope, NeoFlex, and Shaogang, as well as the Neoscope semirigid ureteroscope. The functional capabilities (deflection, irrigation, and optical properties) of each ureteroscope are also discussed.

Fiberoptic versus Digital: A Comparison of Durability and Cost Effectiveness of the Two Flexible Ureteroscopes.

AIMS: We aimed to evaluate the durability and cost effectiveness of the latest digital flexible ureterescope by comparing it with the conventional fiberoptic one. MATERIALS AND METHODS: Data of patients who underwent retrograde intrarenal surgery between January 2013 and December 2014 were collected. Fiberoptic Flex-X2 or digital Cobra vision flexible ureteroscopes were used for the procedures. The comparison of both ureteroscopes was performed in terms of patient and stone characteristics, operative outcomes, durability, and cost effectiveness. RESULTS: A total of 105 patients were evaluated for the study. The patient and stone characteristics and operative outcomes were similar between the groups. Overall, 54 and 51 procedures were performed using Flex-X2 and Cobra vision, respectively, before they were sent for renovation. The purchase prices were USD 29,500 for Flex-X2 and USD 58,000 for Cobra vision. Costs of per case were determined as USD 549.29 for Flex-X2 and as USD 1,137.25 for Cobra vision. Per minute working time costs were USD 772.04 and 1,471.33 for Flex-X2 and Cobra vision respectively. CONCLUSIONS: The digital Cobra vision has high costs without any difference in durability as compared to Flex-X2. Moreover, it has no benefit over Flex-X2 in terms of surgical outcomes.