Experts' recommendations in laser use for the treatment of urolithiasis: a comprehensive guide by the European Section of Uro-Technology (ESUT) and Training-Research in Urological Surgery and Technology (T.R.U.S.T.)-Group.

PURPOSE: To identify laser lithotripsy settings used by experts for specific clinical scenarios and to identify preventive measures to reduce complications. METHODS: After literature research to identify relevant questions, a survey was conducted and sent to laser experts. Participants were asked for preferred laser settings during specific clinical lithotripsy scenarios. Different settings were compared for the reported laser types, and common settings and preventive measures were identified. RESULTS: Twenty-six laser experts fully returned the survey. Holmium-yttrium-aluminum-garnet (Ho:YAG) was the primary laser used (88%), followed by thulium fiber laser (TFL) (42%) and pulsed thulium-yttrium-aluminum-garnet (Tm:YAG) (23%). For most scenarios, we could not identify relevant differences among laser settings. However, the laser power was significantly different for middle-ureteral (p = 0.027), pelvic (p = 0.047), and lower pole stone (p = 0.018) lithotripsy. Fragmentation or a combined fragmentation with dusting was more common for Ho:YAG and pulsed Tm:YAG lasers, whereas dusting or a combination of dusting and fragmentation was more common for TFL lasers. Experts prefer long pulse modes for Ho:YAG lasers to short pulse modes for TFL lasers. Thermal injury due to temperature development during lithotripsy is seriously considered by experts, with preventive measures applied routinely. CONCLUSIONS: Laser settings do not vary significantly between commonly used lasers for lithotripsy. Lithotripsy techniques and settings mainly depend on the generated laser pulse's and generator settings' physical characteristics. Preventive measures such as maximum power limits, intermittent laser activation, and ureteral access sheaths are commonly used by experts to decrease thermal injury-caused complications.

Longer is Better for Endoscopic Follow-up of Upper Tract Urothelial Carcinoma After Ureteroscopic Treatment: An Evaluation Spanning 10 Years of Data.

BACKGROUND: Tumour recurrences are frequent among patients with upper tract urothelial carcinoma (UTUC) treated with ureteroscopy (URS). Therefore, guidelines recommend a strict follow-up regimen, but there is little evidence on how to do this. OBJECTIVE: To analyse outcomes during our follow-up regimen and the impact on treatment in terms of ipsilateral UTUC recurrence, treatment conversion, and tumour upgrading, and to evaluate potential prognostic factors, including second-look URS outcomes. A secondary objective was to evaluate survival outcomes. DESIGN, SETTING, AND PARTICIPANTS: The single-centre cohort included all adult patients with nonmetastatic UTUC treated with URS from January 2010 to December 2020. Follow-up involved endoscopy at 3-mo intervals in the first year, then at 6-mo intervals up to year 3, and yearly thereafter. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Descriptive analyses were performed for the follow-up outcomes. The Andersen-Gill model for recurrent event analysis was used to analyse tumour recurrences, and multivariable Cox regression to analyse for predictors for treatment conversion in low-grade tumours. RESULTS AND LIMITATIONS: We analysed 71 patients with median follow-up of 49.5 mo. The overall 2-yr recurrence-free survival (RFS) rate was 22%. In low-grade disease, the 1-yr RFS rate was 50% and the 2-yr RFS rate was 29%. Treatment was converted to radical nephroureterectomy for 23 patients, at a median time to conversion of 9.9 mo. Upgrading was seen in 13 patients, at a median time to upgrading of 21.9 mo. No factors were prognostic for either tumour recurrence or treatment conversion. The 5-yr OS, CSS, and MFS rates were 82%, 86%, and 84%, respectively. CONCLUSIONS: Our data show that it is rational to extend endoscopic follow-up for UTUC treated with URS, as clinically relevant events (treatment conversion and tumour upgrading) occur beyond the current 6-mo guideline recommendation. Second-look URS outcomes were not prognostic for tumour recurrence or treatment conversion during follow-up. PATIENT SUMMARY: Our study results show that for patients with cancer of the upper urinary tract treated with kidney-sparing surgery through a small telescope called a ureteroscope (URS), most of the clinically relevant events (treatment conversion and tumour upgrading) occur outside the current recommended follow-up of 6 months. Therefore, URS follow-up should be extended for these patients.

Positioning the role of urine cytology within the diagnostic pathway for UTUC: supportive but inconclusive.

PURPOSE: With the introduction of kidney-sparing surgery (KSS) for low-risk Upper Tract Urothelial Carcinoma (UTUC), correct risk-stratification has become crucial. High-grade cytology is one of the decisive variables to stratify a tumor as high-risk. To position the role of urine cytology in the diagnostic pathway of UTUC patients, we evaluated the accuracy of urine cytology by comparing the outcomes with histopathology. METHOD: Patients with UTUC evaluated between 2010 and 2020, and diagnosed by imaging, cytology and histopathology were selected. Descriptive statistics were used to compare cytology with histopathological outcomes using crosstabs. Clinical performance characteristics of cytology were determined for the presence of a malignancy. RESULTS: This study included 176 patients with confirmed histopathological UTUC. Concordance between cytology and biopsy results was found in 14.8% of low-grade tumors and 16.8% of high-grade tumors. Comparing cytology with radical nephroureterectomy (RNU) specimens revealed concordance rates of 1.6% for low-grade tumors and 22.9% for high-grade tumors. Notably, 51.1% of urine cytology results were false negative. Sensitivity for detecting high-grade and low-grade tumors with a positive urine cytology was 56.6% and 52.6%, respectively, with specificities of 54.8% and 37.2%. CONCLUSION: In the current study, cytology appears to exhibit limited reliability when used as a sole diagnostic tool for assessing tumor grade and consequently risk stratification. It is imperative to recognize these limitations, optimize urine sampling techniques, and leverage a combination of diverse diagnostic methods for the most effective and individualized treatment decision-making.

Experts' recommendations in laser use for the treatment of upper tract urothelial carcinoma: a comprehensive guide by the European Section of Uro-Technology (ESUT) and Training Research in Urological Surgery and Technology (T.R.U.S.T.) group.

PURPOSE: To highlight and compare experts' laser settings during endoscopic laser treatment of upper tract urothelial carcinoma (UTUC), to identify measures to reduce complications, and to propose guidance for endourologists. METHODS: Following a focused literature search to identify relevant questions, a survey was sent to laser experts. We asked participants for typical settings during specific scenarios (ureteroscopy (URS), retrograde intrarenal surgery (RIRS), and percutaneous treatment). These settings were compared among the reported laser types to find common settings and limits. Additionally, we identified preventive measures commonly applied during surgery. RESULTS: Twenty experts completed the survey, needing a mean time of 12.7 min. Overall, most common laser type was Holmium-Yttrium-Aluminum-Garnet (Ho:YAG) (70%, 14/20) followed by Thulium fiber laser (TFL) (45%, 9/20), pulsed Thulium-Yttrium-Aluminum-Garnet (Tm:YAG) (3/20, 15%), and continuous wave (cw)Tm:YAG (1/20, 5%). Pulse energy for the treatment of distal ureteral tumors was significantly different with median settings of 0.9 J, 1 J and 0.45 J for Ho:YAG, TFL and pulsed Tm:YAG, respectively (p = 0.048). During URS and RIRS, pulse shapes were significantly different, with Ho:YAG being used in long pulse and TFL in short pulse mode (all p < 0.05). We did not find further disparities. CONCLUSION: Ho:YAG is used by most experts, while TFL is the most promising alternative. Laser settings largely do not vary significantly. However, further research with novel lasers is necessary to define the optimal approach. With the recent introduction of small caliber and more flexible scopes, minimal-invasive UTUC treatment is further undergoing an extension of applicability in appropriately selected patients.

Is It the Load That Breaks You or the Way You Carry It: How Demanding Is Endourology?

Objective: Surgical outcomes are dependent on multiple factors. Besides patient-related or procedure-related factors, several surgeon-related factors contribute to surgical outcomes. The Surgery Task Load Index (SURG-TLX) questionnaire helps to assess the impact of several stressors on the perceived demands of surgeons during surgery. In this study, we evaluate the applicability of the SURG-TLX questionnaire for endourologic procedures and set a first point of reference. Materials and Methods: Between March and August 2022, 15 urologists and urology residents at a tertiary referral center for endourology completed the SURG-TLX questionnaire after endourologic procedures. After data acquisition, all participants were asked to evaluate the applicability of the questionnaire for endourologic procedures. Results: A total of 130 procedures were included between March and August 2022. Situational stress had the lowest median score (3.0/20; interquartile range [IQR] 2.0-7.0) and task complexity the highest (5.0/20; IQR 3.0-8.0). After weighing, the dimensions showed different proportions when compared with the nonweighted scores. Distractions received the highest score (15.0/100; IQR 7.5-32.8), temporal demands (6.0/100; IQR 3.0-12.5), and situational stress the lowest (6.0/100; IQR 2.0-21.0). This was caused by the higher weight that was attributed to distractions (3.4/5), as opposed to task complexity (2.6/5). In the questionnaire regarding applicability of the SURG-TLX, the overall satisfaction (6.0/10; IQR 5.0-7.0) and clarity (6.5/10; IQR 5.0-7.5) were moderate. The user-friendliness and applicability of the questionnaire were rated high (7.0/10; IQR 5.5-8.0 and 7.0/10; IQR 6.0-8.0, respectively) and task load (3.0/10; IQR 2.0-5.0) and time load (2.0/10; IQR 2.0-3.5) low. Conclusion: The SURG-TLX questionnaire is appropriate to assess the different dimensions of workload during endourologic procedures. Furthermore, the perceived workload during endourologic procedures is relatively low.

Donor kidney lithiasis and back-table endoscopy: a successful combination.

INTRODUCTION: Urolithiasis in renal allografts is relatively rare with an incidence of 0.17-4.40%. It is nonetheless an important issue, as there is a risk of obstruction, sepsis and even loss of the renal allograft. The management of stones in renal allografts remains challenging because of the anatomy, the renal denervation and the use of immunosuppressive medication. CASE PRESENTATION: This report discusses the ex-vivo treatment of asymptomatic nephrolithiasis in a living donor kidney allograft. A CT abdomen revealed a lower pole stone (5.9 × 5.5 × 5.0 mm; 920 HU) in the right kidney of the potential donor. After multidisciplinary discussion, it was decided to procure the right kidney despite the presence of a documented nephrolithiasis. After discussion with both donor and recipient, an ex-vivo flexible ureterorenoscopy for stone removal on the back table just before implantation of the allograft was planned. The stone was found in the lower pole covered by a thin film of the urothelium. The thin film of urothelium was opened with a laser and the stone fragments were retrieved with a basket. CT after one month showed no residual stones in the transplanted kidney. CONCLUSION: Back-table endoscopy in a renal allograft is a feasible technique and should be discussed as an option in case of urolithiasis in a kidney that is considered for transplantation. Furthermore, the appropriate treatment of donor kidney lithiasis is another, although rare, method to expand the living donor renal allograft pool.

How Reliable Is Endoscopic Stone Recognition? A Comparison Between Visual Stone Identification and Formal Stone Analysis.

Objective: To assess the diagnostic accuracy and intra-observer agreement of endoscopic stone recognition (ESR) compared with formal stone analysis. Introduction: Stone analysis is a corner stone in the prevention of stone recurrence. Although X-ray diffraction (XRD) and infrared spectroscopy are the recommended techniques for reliable formal stone analysis, this is not always possible, and the process takes time and is costly. ESR could be an alternative, as it would give immediate information on stone composition. Materials and Methods: Fifteen endourologists predicted stone composition based on 100 videos from ureterorenoscopy. Diagnostic accuracy was evaluated by comparing the prediction from visual assessment with stone analysis by XRD. After 30 days, the videos were reviewed again in a random order to assess intra-observer agreement. Results: The median diagnostic accuracy for calcium oxalate monohydrate was 54% in questionnaire 1 (Q1) and 59% in questionnaire 2 (Q2), whereas calcium oxalate dihydrate had a median diagnostic accuracy of 75% in Q1 and 50% in Q2. The diagnostic accuracy for calcium hydroxyphosphate was 10% in Q1 and 13% in Q2. The median diagnostic accuracy for calcium hydrogen phosphate dihydrate and calcium magnesium phosphate was 0% in both questionnaires. The median diagnostic accuracy for magnesium ammonium phosphate was 20% in Q1 and 40% in Q2. The median diagnostic accuracy for uric acid was 22% in both questionnaires. Finally, there was a diagnostic accuracy of 60% in Q1 and 80% in Q2 for cystine. The intra-observer agreement ranged between 45% and 72%. Conclusion: Diagnostic accuracy of ESR is limited and intra-observer agreement is below the threshold of acceptable agreement.

Survival and Long-term Effects of Kidney-sparing Surgery Versus Radical Nephroureterectomy on Kidney Function in Patients with Upper Urinary Tract Urothelial Carcinoma.

Background: Current European Association of Urology (EAU) guidelines discriminate between high- and low-risk upper urinary tract urothelial carcinoma (UTUC) to determine treatment by means of radical nephroureterectomy (RNU) or kidney-sparing surgery (KSS). Objective: To compare long-term oncological outcomes and renal function for patients with UTUC treated by RNU versus KSS. Design setting and participants: A retrospective cohort study, including 186 renal units with nonmetastatic UTUC treated in a tertiary referral centre between 2010 and 2021, was conducted. Intervention: RNU, ureterorenoscopy, percutaneous tumour resection, and segmental ureteral resection. Outcome measurements and statistical analysis: Recurrence-free survival, metastasis-free survival (MFS), overall survival (OS), cancer-specific survival (CSS), and renal function were analysed by means of the log-rank test and the independent-sample t test. Results and limitations: OS was 71.1% for the RNU group and 81.9% for the KSS group. In a cohort matched for propensity weight based on EAU risk stratification progression-free survival (PFS; RNU 96.0%; KSS 86.0%), MFS (RNU 72.0%; KSS 84.0%), CSS (RNU 84.0%; KSS 86.0%), and OS (RNU 76.0%; KSS 76.0%) were all similar between both groups. No significant differences in renal function were seen at 2 and 5 yr after the intervention. Although this series represents the largest cohort of (high-risk) UTUC patients treated by means of KSS to date, it is not suitable for performing a multivariate analysis. Conclusions: PFS, MFS, CSS, and OS were all comparable when analysing the RNU and KSS groups. Similar results for groups with evenly distributed risk factors and a large percentage of high-risk disease suggest that current risk stratification might not be accurate in discriminating low-risk from high-risk disease. Patient summary: In this report, we looked at outcomes for upper urinary tract urothelial carcinoma in a specialised hospital. We conclude that kidney-sparing surgery and radical nephroureterectomy have comparable outcomes and that risk factors for worse outcome might not be identified correctly.

European Association of Urology Section of Urolithiasis and International Alliance of Urolithiasis Joint Consensus on Retrograde Intrarenal Surgery for the Management of Renal Stones.

BACKGROUND: Retrograde intrarenal surgery (RIRS) has become the preferred treatment modality for nephrolithiasis. However, because of ongoing uncertainties regarding the optimal perioperative management, operative technique, and postoperative follow-up, as well as a lack of standardization for outcome reporting, consensus is needed to achieve more uniform clinical practice worldwide. OBJECTIVE: To develop recommendations for RIRS on the basis of existing data and expert consensus. DESIGN, SETTING, AND PARTICIPANTS: A protocol-driven, three-phase study was conducted by the European Association of Urology Section of Urolithiasis (EULIS) and the International Alliance of Urolithiasis (IAU). The process included: (1) a nonsystematic review of the literature to define domains for discussion; (2) a two-round modified Delphi survey involving experts in this field; and (3) an additional group meeting and third-round survey involving 64 senior representative members to formulate the final conclusions. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The results from each previous round were returned to the participants for re-evaluation of their decisions during the next round. The agreement threshold was set at 70%. RESULTS AND LIMITATIONS: The panel included 209 participants who developed 29 consensus statements on the following topics of interest: (1) perioperative infection management; (2) perioperative antithrombotic therapy; (3) fundamentals of the operative technique; and (4) standardized outcome reporting. Although this consensus can be considered as a useful reference for more clinically oriented daily practice, we also acknowledge that a higher level of evidence from further clinical trials is needed. CONCLUSIONS: The consensus statements aim to guide and standardize clinical practice and research on RIRS and to recommend standardized outcome reporting. PATIENT SUMMARY: An international consensus on the best practice for minimally invasive surgery for kidney stones was organized and developed by two international societies. It is anticipated that this consensus will provide further guidance to urologists and may help to improve clinical outcomes for patients.

How to evaluate a flexible ureterorenoscope? Systematic mapping of existing evaluation methods.

OBJECTIVES: The objective of this study was to identify, map and review scope-related and user-related parameters used to evaluate the quality of flexible ureterorenoscopes. Thereby identifying key items and variability in grading systems. METHODS: A literature search of four databases (MEDLINE [Ovid], EMBASE [Ovid], Web of Science, Google scholar and the Cochrane Library) was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines encompassing articles published up to August 2020. A total of 2386 articles were screened. RESULTS: A total of 48 articles were included in this systematic scoping review. All studies had a prospective design. Five key items in the assessment of flexible ureterorenoscopy were distinguished: 'Manoeuvrability' (87.5%), 'Optics' (64.6%), 'Irrigation' (56.3%), 'Handling' (39.6%) and 'Durability' (35.4%). After regrouping, every key item could be divided into specific subcategories. However, the quality assessment showed a wide variation in denomination, method of measurement, circumstances of measurement, tools used during measurements, number of measurements performed, number of observers, and units of outcomes. CONCLUSION: The research field regarding quality assessment of ureterorenoscopes is heterogeneous. In this systematic scoping review we identified five key parameters: Manoeuvrability, Optics, Irrigation, Handling and Durability, used to grade flexible ureterorenoscopes. However, within these categories we found a wide variety in terms of method of measurements. A standardised, uniform grading tool is required to assess and compare the quality of flexible ureterorenoscopes in the future.

Fluoroscopy-use during ureterorenoscopy: are urologists concerned about radiation exposure? A nationwide survey in Belgium and The Netherlands.

INTRODUCTION: To evaluate the use and awareness of radiation during URS among Belgian and Dutch urologists. MATERIAL AND METHODS: An online questionnaire was send to all members of the Belgian and Dutch Association of Urology. RESULTS: 170 urologists finished the complete questionnaire. 10% of the respondents are not familiar with the ALARA-principle. 29% starts with a KUB and 48% makes an XRPG at the beginning of the procedure. 85% uses fluoroscopy to place a wire or ureteral access sheet, 18% during stone treatment, 59% to screen for missed stones or calyces, 90% to place a JJ-stent or ureter-catheter and 23% to check for extravasation. 82% do not document radiation data. 51% does not wear a dosimeter during fluoroscopy. Almost all wear a lead apron during fluoroscopy, 47% uses additional thyroid shields and only 4% uses lead glasses. 88% intentionally reduces fluoroscopy time, 75% reduces the exposed area with a diaphragm, 72% brings the radiation source close to the patient and 44% uses pulsed fluoroscopy. CONCLUSION: There is a wide variety in the use and awareness of radiation during URS. To further reduce radiation and its negative effect for patients and medical staff, awareness about radiation safety should increase among urologists.

The effect of additional drug therapy as metaphylaxis in patients with cystinuria: a systematic review.

INTRODUCTION: To systematically review the effect of additional drug therapy as metaphylaxis in patients with cystinuria. EVIDENCE ACQUISITION: A literature search of three databases (MEDLINE, Embase and the Cochrane Library) was performed according to the PRISMA-guidelines enclosing articles published up to May 2019. A total of 1117 articles were screened. Thirty-four publications met the inclusion criteria for this review. EVIDENCE SYNTHESIS: Male-female ratio in the studied cohorts was 49.9% - 50.1%. The majority of studies showed a positive effect in reducing stone events and/or urinary cystine excretion. D-Penicillamine showed success in 13/14 (92%) studies, whereas Tiopronin-treatment showed a reduction in all (8/8; 100%) studies. All studies on Captopril (4/4) showed a decrease, however not all significant. The same is true for studies on Thiols in combination with Captopril (2/2). Furthermore, Tiopronin showed less side effects compared to D-penicillamine, respectively 30% and 37%. Captopril showed the least adverse events, with one event in nine patients. CONCLUSIONS: The evidence on benefit of additional drug therapy in patients with cystinuria is scarce. All studied medications showed an effect on stone event and urinary cystine excretion, when used in addition to hyperhydration, alkalization and a diet low on methionine. Based on this systematic review, no drug can be preferred over another. An important aspect in the choice of drug is the risk of side effects. Therefore, the choice of additional drug should be personalized for every patient where the risk of side effects should be taken into consideration.

Validation of Confocal Laser Endomicroscopy Features of Bladder Cancer: The Next Step Towards Real-time Histologic Grading.

BACKGROUND: Cystoscopy enables the visualisation of suspicious bladder lesions but lacks the ability to provide real-time histopathologic information. Confocal laser endomicroscopy (CLE) is a probe-based optical technique that can provide real-time microscopic images. This high-resolution optical imaging technique may enable real-time tumour grading during cystoscopy. OBJECTIVE: To validate and adapt CLE criteria for bladder cancer diagnosis and grading. DESIGN, SETTING, AND PARTICIPANTS: Prospectively, 73 patients scheduled for transurethral resection of bladder tumour(s) were included. CLE imaging was performed intraoperatively prior to en bloc resection. Histopathology was the reference standard for comparison. INTERVENTION: Cystoscopic CLE imaging. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Three independent observers evaluated the CLE images to classify tumours as low- or high-grade urothelial carcinoma (UC), or benign lesions. Interobserver agreement was calculated with Fleiss kappa analysis and diagnostic accuracy with 2×2 tables. RESULTS AND LIMITATIONS: Histopathology of 66 lesions (53 patients) revealed 25 low-grade UCs, 27 high-grade UCs, and 14 benign lesions. For low-grade UC, most common features were papillary configuration (100%), distinct cell borders (81%), presence of fibrovascular stalks (79%), cohesiveness of cells (77%), organised cell pattern (76%), and monomorphic cells (67%). A concordance between CLE-based classification and histopathology was found in 19 cases (76%). For high-grade UC, pleomorphic cells (77%), indistinct cell borders (77%), papillary configuration (67%), and disorganised cell pattern (60%) were the most common features. A concordance with histopathology was found in 19 cases (70%). In benign lesions, the most prevalent features were disorganised cell pattern (57%) and pleomorphic cells (52%), and a concordance with histopathology was found in four cases (29%). CONCLUSIONS: The CLE criteria enable identification of UC. CLE features correlate to histopathologic features that may enable real-time tumour grading. However, flat lesions remain difficult to classify. PATIENT SUMMARY: Confocal laser endomicroscopy may enable real-time cancer differentiation during cystoscopy, which is important for prognosis and disease management.

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.

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.

Upper Tract Urothelial Carcinoma Grade Prediction Based on the Ureteroscopic Appearance: Caution Should be Taken.

OBJECTIVES: To investigate the diagnostic accuracy, inter-rater and intrarater agreement of grade predictions based on the visual appearance of papillary upper tract urothelial carcinoma (UTUC) during digital ureteroscopy. METHODS: Nine urologists predicted the histopathologic grade of 64 papillary UTUC (low-grade vs high-grade) by assessing the visual appearance of the tumors in videos from digital ureteroscopy. The diagnostic accuracy was estimated by comparing the grade predictions with the histopathology from colocalized biopsies. Inter-rater agreement was assessed by pairwise inter-rater percentage agreement and Fleiss Kappa analysis. The videos were rated in a random order again 30 days after the first assessment to evaluate the intrarater percentage agreement. RESULTS: Low-grade tumors were predicted correctly in 37%-85% of the cases with a median concordance of 59% for questionnaire 1 and 66% for questionnaire 2. High-grade tumors were predicted correctly in 26%-91% of the cases with a median concordance of 52% and 61% for each questionnaire. The median pairwise inter-rater percentage agreement was 66% for both questionnaires with a Fleiss Kappa of 0.29 and 0.38, respectively. The median intrarater percentage agreement was 81%. CONCLUSION: The histopathologic grade of UTUC is essential to the risk-stratification for treatment selection. Predictions of the histopathologic grade based on the visual appearance of papillary UTUC with digital ureteroscopy are often incorrect in comparison with biopsy results and yield low inter-rater agreement. Urologists must be aware of these limitations in the assessment of the tumor grade during digital ureteroscopy to warrant good clinical practice.

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.

Durability of Flexible Ureteroscopes: A Prospective Evaluation of Longevity, the Factors that Affect it, and Damage Mechanisms.

BACKGROUND: Flexible ureteroscopy is an established treatment modality for evaluating and treating abnormalities in the upper urinary tract. Reusable ureteroscope (USC) durability is a significant concern. OBJECTIVE: To evaluate the durability of the latest generation of digital and fiber optic reusable flexible USCs and the factors affecting it. DESIGN, SETTING, PARTICIPANTS: Six new flexible USCs from Olympus and Karl Storz were included. The primary endpoint for each USC was its first repair. Data on patient and treatment characteristics, accessory device use, ureteroscopy time, image quality, USC handling, disinfection cycles, type of damage, and deflection loss were collected prospectively. INTERVENTION: Ureteroscopy. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: USC durability was measured as the total number of uses and ureteroscopy time before repair. USC handling and image quality were scored. After every procedure, maximal ventral and dorsal USC deflection were documented on digital images. RESULTS AND LIMITATIONS: A total of 198 procedures were performed. The median number of procedures was 27 (IQR 16-48; 14h) for the six USCs overall, 27 (IQR 20-56; 14h) for the digital USCs, and 24 (range 10-37; 14h) for the fiber optic USCs. Image quality remained high throughout the study for all six USCs. USC handling and the range of deflection remained good under incremental use. Damage to the distal part of the shaft and shaft coating was the most frequent reason for repair, and was related to intraoperative manual forcing. A limitation of this study is its single-center design. CONCLUSIONS: The durability of the latest reusable flexible USCs in the current study was limited to 27 uses (14h). Damage to the flexible shaft was the most important limitation to the durability of the USCs evaluated. Prevention of intraoperative manual forcing of flexible USCs maximizes their overall durability. PATIENT SUMMARY: Current flexible ureteroscopes proved to be durable. Shaft vulnerability was the most important limiting factor affecting durability.

Ex-vivo study in nephroureterectomy specimens defining the role of 3-D upper urinary tract visualization using optical coherence tomography and endoluminal ultrasound.

Minimal invasive endoscopic treatment for upper urinary tract urothelial carcinoma (UUT-UC) is advocated in patients with low-risk disease and limited tumor volume. Diagnostic ureterorenoscopy combined with biopsy is the diagnostic standard. This study aims to evaluate two alternative diagnostic techniques for UUT-UC: optical coherence tomography (OCT) and endoluminal ultrasound (ELUS). Following nephroureterectomy, OCT, ELUS, and computed tomography (CT) were performed of the complete nephroureterectomy specimen. Visualization software (AMIRA®) was used for reconstruction and coregistration of CT, OCT, and ELUS. Finally, CT was used to obtain exact probe localization. Coregistered OCT and ELUS datasets were compared with histology. Coregistration with three-dimensional CT makes exact data matching possible in this ex-vivo setting to compare histology with OCT and ELUS. In OCT images of normal-appearing renal pelvis and ureter, urothelium, lamina propria, and muscularis were visible. With ELUS, all anatomical layers of the ureter could be distinguished, besides the urothelial layer. ELUS identified suspect lesions, although exact staging and differentiation between noninvasive and invasive lesions were not possible. OCT provides high-resolution imaging of normal ureter and ureter lesions. ELUS, however, is of limited value as it cannot differentiate between noninvasive and invasive tumors.

Outcome from 5-year live surgical demonstrations in urinary stone treatment: are outcomes compromised?

PURPOSE: To compare intra- and post-operative outcomes of endourological live surgical demonstrations (LSDs) and routine surgical practice (RSP) for urinary stones. METHODS: Consecutive ureterorenoscopic (URS) and percutaneous (PNL) urinary stone procedures over a 5-year period were reviewed. Procedures were divided into LSDs and RSP. Differences between the groups were separately analysed for URS and PNL. Primary outcomes included intra- and post-operative complication rates and grades. Secondary outcomes were operation time, length of hospital stay, stone-free rate, and retreatment rate. Pearson's Chi-square analysis, Mann-Whitney U test, and logistic and linear regression were used to compare outcomes between LSDs and RSP. RESULTS: During the study period, we performed 666 URSs and 182 PNLs, and 151 of these procedures were LSDs. Among URSs, the overall intra-operative complication rate was 3.2% for LSDs and 2.5% for RSP (p = 0.72) and the overall post-operative complication rate was 13.7% for LSDs and 8.8% for RSP (p = 0.13). Among PNLs, the overall intra-operative complication rate was 8.9% for LSDs and 5.6% for RSP (p = 0.52) and the overall post-operative complication rate was 28.6% for LSDs and 34.9% for RSP (p = 0.40). For both URSs and PNLs, no statistically significant differences in complication grade scores were observed between LSDs and RSP. Operation time was significantly longer for LSD-URS group, but there was no difference between the PNL groups. There were no significant differences in length of hospital stay and stone-free rate. The retreatment rate was higher in the LSD-URS group compared with RSP-URS group but similar between the PNL groups. Multiple logistic regression analyses, adjusting for confounders, revealed no association between LSD and more or less favourable outcomes as compared to RSP. CONCLUSION: Live surgical demonstrations do not seem to compromise patients' safety and outcomes when performed by specialised endourologists.