INTRODUCTION:Conduitoscopy is a technically demanding procedure with limited opportunities for structured training. We evaluated the educational impact of a 3D-printed ileal conduit simulator on knowledge acquisition and perceived learning among urology trainees and fully qualified urologists (FQU). METHODS:We conducted a prospective, single-group study during a national urology training course in 2024. Participants included U.K.-based resident doctors in year 3 and year 7, as well as FQU; participation was voluntary. Knowledge acquisition was assessed with a five-item multiple-choice questionnaire (MCQ) administered before and after training, while educational experience was evaluated post-training using the Michigan Standard Simulation Experience Scale (MiSSES), covering key educational sections. Comparisons of MCQ scores were analyzed using Welch's t-test, and group differences in survey responses were assessed using Fisher's exact test. Free-text comments were also collected and thematically analyzed to capture participants' perceptions and suggestions. RESULTS:Fifty-three participants completed the study (36 resident doctors in year 3 [RDY3], 9 in year 7 [RDY7], and 8 FQU). Agreement rates were high across all MiSSES sections, with 100% endorsing teaching quality and overall ratings. MCQ scores improved significantly after training (mean 2.55 vs 3.23, p < 0.001; Cohen's d = 0.71). Comparison between RDY3 and the combined RDY7 + FQU group showed a significant difference in self-efficacy (p = 0.003), while no statistically significant differences were observed in fidelity, educational value, or teaching quality. CONCLUSION:The 3D-printed ileal conduit simulator is an effective tool for conduitoscopy training, improving theoretical knowledge and receiving strong endorsement across key educational sections. Participant feedback highlighted its realism and educational value, alongside suggestions for minor refinements. These findings support its integration into structured endourology urology training programs.

OBJECTIVES:To predict spontaneous stone passage (SSP) in uncomplicated acute ureteric colic (AC) using non-contrast computed tomography (NCCT)-based radiomics and machine learning (ML). PATIENTS AND METHODS:This retrospective single-centre study included consecutive patients presenting with stone-related uncomplicated AC between January 2022 and March 2024, confirmed by NCCT. Initial and 4-week follow-up clinical and imaging data were collected, including SSP status. After anonymisation, a semi-automated density-based stone segmentation was performed using 3DSlicer. Radiomic features were extracted (PyRadiomics_v3.1.1). Significant features were selected using the Least Absolute Shrinkage and Selection Operator (LASSO) method. After data splitting (training [80%]-validation [20%]), nine ML models were trained with hyperparameter fine-tuning to predict SSP on the validation set. The primary performance metric was the area under the curve (AUC). RESULTS:A total of 428 patients were included, with a median (interquartile range [IQR]) age of 45 (32-56) years. Most ureteric stones were solitary, with a median (IQR) maximum stone diameter (MSD) of 5.3 (4.1-6) mm and stone volume of 68.8 (22-78.1) mm3. The majority of the stones were proximal rather than distal: 59.6%, were located in the upper ureter, 9.1%, in the middle, and 30.8% in the lower ureter. A pelvic phlebolith was present in 50.9% of cases. The overall SSP rate was 47.9%. Following LASSO selection, seven radiomic features were used for model training and validation: image-original_mean (mean value of all voxels), image-original_maximum (maximum voxel value), original_glrlm_RunEntropy (heterogeneity in grey level run lengths), original_gldm_DependenceVariance (structure irregularity), original_gldm_LargeDependenceEmphasis (voxel homogeneity), original_gldm_LargeDependenceHighGreyLevelEmphasis (homogenous regions with high voxel intensity), original_gldm_LargeDependenceLowGreyLevelEmphasis (homogenous regions with low voxel intensity), along with SSP status. The random forest algorithm achieved the best performance of all tested models with an AUC of 0.79 (95% confidence interval 0.68-0.88) on the validation set (accuracy = 0.72, F1-score = 0.72, sensitivity = 0.69, specificity = 0.76). CONCLUSION:Predicting SSP in uncomplicated AC is feasible using radiomics features extracted from NCCT. Hybrid models, including the stone location could improve their performance. External validation is required, and developing an automated ureteric stone detection algorithm would be necessary to create a fully stand-alone clinical tool.

PURPOSE OF REVIEW:This scoping review synthesizes contemporary evidence on the role of simulation, uro-technology and structured training curricula in shaping the next generation of endourologists, both inside and outside of the operating theatre. RECENT FINDINGS:A broad range of simulation platforms - spanning low-fidelity benchtop models, virtual reality systems and high-fidelity hybrid simulators - have demonstrated validity in endourological training across ureteroscopy, percutaneous nephrolithotomy, transurethral surgery and laparoscopy, with several also showing skill transfer to the clinical environment. Proficiency-based progression curricula such as the Endoscopic Stone Treatment Steps 1 and 2, and the ENTRY project for transurethral bladder tumour resection, represent the current standard of structured competency-based training. Artificial intelligence is rapidly evolving and shaping simulation training by facilitating automated performance assessment and personalized, adaptive feedback. Simulation in paediatric endourology unfortunately remains a considerable gap. SUMMARY:Endourological training is at a turning point in history where simulation and uro-technology are shifting the learning phase away from the operating theatre. Structured, PBP-based curricula with objective performance metrics offer the most robust framework for competency development and new technologies will help individualize the learning pathway, assuring proficiency is reached prior to clinical exposure. Several hurdles still need to be taken before this can be made widely available for all urological trainees.

Objective:To compare in vitro the ablation rates of p-Tm:YAG, TFL and Ho:YAG against synthetic and human stones. Material and Methods:p-Tm:YAG, TFL and Low-Power (LP) Ho:YAG were compared using 270 μm core-diameter laser fibres (CDF); experiments with 200 μm(p-Tm:YAG) and 150 μm-CDF (TFL) were also included. A continuous laser emission was applied through a spiral trajectory for 20 seconds with the laser fibre tip in contact with synthetic hard (HSP) and soft stone phantoms (SSP) submerged in saline. "Dusting" settings for p-Tm:YAG(0,6 J-20 Hz-Flex Long Pulse), TFL(0,5 J-30 Hz-Short Pulse) and Ho:YAG(0,5 J-30 Hz-Long Pulse) and "Fragmentation" settings for p-Tm:YAG(1 J-15 Hz-Captive), TFL(1 J-15 Hz-Short Pulse) and Ho:YAG(1 J-15 Hz-Long Pulse) were analysed. Then, experiments for human calcium oxalate monohydrate (COM), uric acid (UA) and cystine (CYS) stones were performed with single laser pulses at 0.6 J, 0.8 J and 1.0 J for p-Tm:YAG (Captive Fragmenting mode), TFL (Short Pulse) and Ho:YAG (Long Pulse). Synthetic and human stone samples were dried before three-dimensional scanning to measure ablation rates (ARs) and ablation volume per pulse (AVP). Results:For synthetic stones with 270 μm-CDF, the p-Tm:YAG and TFL presented similar ARs, except in Fragmentation against HSP (95,1 ± 13,6vs67 ± 14 p = 0,02, respectively). Both p-Tm:YAG and TFL achieved higher ARs than Ho:YAG in all settings. p-Tm:YAG-200 μm-CDF and TFL-150 μm-CDF presented similar ARs, except in Fragmentation against HSP(78,4 ± 8vs42,5 ± 2,6 mm3/min,p = 0,0002). Both p-Tm:YAG-200 μm-CDF and TFL-150 μm-CDF presented at least 50% higher ARs than 270 μm-Ho:YAG. For human stones with COM, TFL exhibited higher AVP compared to p-Tm:YAG and Ho:YAG across all pulse energies (258,2 ± 213vs81,7 ± 31,9vs41,5 ± 25,4 μm3 p = 0,01, respectively). Against UA, Ho:YAG demonstrated higher AVP compared to TFL and p-Tm:YAG (355,2 ± 161vs99,8 ± 76,7vs292,9 ± 203,1 μm3 p = 0,0005, respectively). For CYS, Ho:YAG presented higher AVP but without significance (99,8 ± 76,7 vs 49,3 ± 36,3 vs 38,8 ± 12,2 μm3, p = 0,09). Conclusion:p-Tm:YAG and TFL achieved higher ARs than LP-Ho:YAG against synthetic stones in vitro. For human stones, TFL achieved the highest AVP against COM while LP-Ho:YAG delivered higher AVPs against UA and CYS, for which TFL performed worst.

This study aimed to assess ureteroscopy’s impact on renal function in patients with a solitary kidney (SK), where nephron preservation is paramount. With the rising prevalence of SKs due to congenital anomalies or acquired conditions, understanding the safety profile of ureteroscopy, particularly its effects on renal function, seems essential. A literature search following PRISMA guidelines was conducted to identify reports published until May 2024. Eligible studies were included if they focused on ureteroscopy in SK patients and reported renal function outcomes. Data extraction and bias assessment were performed using standardized protocols as Joanna Briggs Institute’s checklist for non-randomized studies. Renal function changes (eGFR or serum creatinine), complications, and follow-up data were analyzed. Outcomes included acute kidney injury (AKI) and persistent renal function deterioration, as defined by the Collège-Français-des-Enseignants-d’Urologie (CFEU) criteria. 15 studies were included, involving 615 patients. The renal function remained stable in ten (67

Flexible Ureteroscopy (FURS) in patients with a solitary kidney (SK) has been sparsely studied, especially its safety. Available literature suggests that the renal function remains stable after FURS with low evidence. We aimed to assess and predict the postoperative renal function after FURS in patients with SK, using Machine Learning (ML) models. A dualcenter retrospective study was conducted between 2013 and 2023, including patients undergoing FURS in solitary kidneys. Demographic, peri-operative data, pre- and postoperative serum creatinine and estimated Glomerular Filtration Rate(eGFR) were collected. Multivariate analysis intended to identify risk factors for renal function decline. After data splitting, 12 ML models were trained and tested to predict the 3 months postoperative serum creatinine. A total of 87 patients were included. 84

OBJECTIVES:To evaluate Urologists' perception regarding stone volume (SV) to assess the stone burden in current practice. Whilst SV might be considered as the most accurate measure of stone burden, international guidelines are to date based on maximum stone diameter (MSD). SUBJECTS AND METHODS:An on-line survey (four parts, 22 multiple choice questions) designed by international Endourology experts was submitted to the urological community between December 2023 and January 2024. In addition to questions on clinical practice, stone burden reporting and lithotripsy methods, participants were asked to intuitively estimate the spherical SV equivalent of several stone sizes and situations. Interest in SV overall, including knowledge about SV measurement tools were also investigated. RESULTS:A total of 218 participants completed the survey, of whom 83% were male and 43% were aged 30-40 years. Approximately two thirds were European (63%), consultant Urologists (66%) and worked in a university hospital (66%). In all, 79% had specialist Endourology training and 44% declared more than half of their surgical activity was dedicated to Endourology. Although MSD was preferred to SV (67% vs 3%) for preoperative stone burden estimation, 64% of respondents were 'very keen' to have a tool to provide SV in future. The rate of correct intuitive SV estimations decreased with case complexity (from 40% to 20%). Endourology experts and academic Urologists were keener to adopt SV in practice but their ability to estimate SV was similar to those who were not Endourology trained or in non-academic posts. CONCLUSIONS:Urologists agree that SV provides a better estimation for stone burden than MSD. However, intuitive SV estimation based on stone diameters seems insufficient, hence readily accessible SV estimation tools are warranted for using SV in routine practice.

“Kidney Stone Calculator” (KSC) helps to plan flexible ureteroscopy, providing the stone volume (SV) and an estimated duration of laser lithotripsy (eLD). eLD is calculated from in vitro ablation rates and SV. KSC’s accuracy has been demonstrated with a mean difference between eLD and effective LD (EfLD) of 18.8

Lower pole stones (LPSs) frequently cause significant morbidity, necessitating effective intervention strategies. We systematically reviewed the evidence for treatment of LPSs with extracorporeal shock wave lithotripsy (ESWL), flexible ureterorenoscopy (FURS), and percutaneous nephrolithotomy (PCNL) previously in 2015. In this update, we have included 16 new randomised controlled trials plus eight from our original review (24 in total). Despite the increase in available trials, the certainty of evidence remains moderate for stone-free rates (SFRs), underscoring the on-going need for more robust trials in this domain. FURS demonstrated superior efficacy in achieving SFRs to ESWL (risk ratio [RR] 1.19, 95% confidence interval [CI] 1.05, 1.35), although the absolute difference remains modest. ESWL may lead to fewer complications, and FURS could result in more unplanned procedures and retreatments. It remains unclear whether there are differences in quality of life and cost estimates vary depending on the country. PCNL offers a marginal yet statistically significant advantage over FURS in terms of SFRs (RR 1.07, 95% CI 1.01, 1.12), but it is unclear whether there are differences in unplanned procedures, retreatments, or complications, and there was conflicting evidence about health status and return to normal activities. SFRs were superior with PCNL to those with ESWL (RR 1.42 95% CI 1.28, 1.58). Unplanned procedures and retreatments were generally fewer for PCNL, and complications were fewer for ESWL. The cost effectiveness of each modality is highly dependent on the health care system and country-specific economic factors. The overall certainty of the evidence remains unchanged, with only moderate improvements in certain domains.

Suction devices such as flexible and navigable suction ureteral access sheath (FANS) are promising tools to reach the zero-fragment rate (ZFR) after flexible ureteroscopy (FURS) and laser lithotripsy. FANS could especially be useful for lower pole stones (LPS), avoiding postoperative retained stone dust. Using Machine Learning (ML) models, we aimed to predict the ZFR after FURS with FANS and secondarily the possible access to the lower pole (LP). Data from patients who underwent FURS in 25 centers worldwide were prospectively collected (Aug 2023–Jan 2024). Exclusion criteria were abnormal renal anatomy and ureteral stones. ZFR and LP access were respectively defined as the total absence of residual fragments on computed tomography at 1-month follow-up and the ability to place the FANS into a LP calyx. After data normalization and splitting (training-test (80–20

Background:Renal tract stone disease is common. The three intervention options are shockwave lithotripsy, flexible ureteroscopic stone treatment and keyhole surgery. Objectives:To determine which of shockwave lithotripsy, flexible ureteroscopic stone treatment and keyhole surgery offer the best outcomes in terms of health and quality of life, clinical effectiveness and cost-effectiveness for people with lower pole kidney stones. Design:The PUrE study comprised two pragmatic multicentre, open-label, superiority randomised controlled trials: RCT1 for lower pole stones ≤ 10 mm and RCT2 for lower pole stones > 10 and ≤ 25 mm. Setting:National Health Service Urology departments. Participants:Adults presenting with lower pole renal stones, able to undergo any of the treatments and complete trial procedures. Intervention:Eligible participants were randomised in RCT1 to flexible ureteroscopic stone treatment or shockwave lithotripsy; and in RCT2 to flexible ureteroscopic stone treatment or keyhole surgery. Main outcome measures:The primary outcome measure was health status 'area under the curve', measured weekly to 12 weeks post intervention with the EuroQol-5 Dimensions, five-level version. The primary economic outcome was the incremental cost per quality-adjusted life-year gained at 12 months from randomisation. Results:RCT1: A total of 461 participants were randomised: 231 to flexible ureteroscopic stone treatment; and 230 to shockwave lithotripsy. RCT2: A total of 159 participants were randomised: 73 to flexible ureteroscopic stone treatment; and 86 to keyhole surgery. Primary outcome:RCT1: The mean health status area under the curve was 0.807 (standard deviation 0.205) in the flexible ureteroscopic stone treatment group (n = 164) and 0.826 (standard deviation 0.207) in the shockwave lithotripsy group (n = 188). The between-group difference, 0.024 (95% confidence interval -0.004 to 0.053), was a small difference in favour of flexible ureteroscopic stone treatment after correcting for a baseline imbalance. Complete stone clearance was higher with flexible ureteroscopic stone treatment (72%) than shockwave lithotripsy (36%). RCT2: The mean health status area under the curve was 0.794 (standard deviation 0.198) in the flexible ureteroscopic stone treatment group (n = 57) and 0.818 (standard deviation 0.217) in the keyhole surgery group (n = 63). The between-group difference, -0.07 (95% confidence interval -0.11 to -0.02), was a borderline meaningful difference favouring keyhole surgery. Complete stone clearance was higher with keyhole surgery (71%) than flexible ureteroscopic stone treatment (48%). Economic evaluation:RCT1: Flexible ureteroscopic stone treatment is more costly (£1138; 95% confidence interval £646 to £1631) and produces 0.017 (95% confidence interval -0.008 to 0.043) additional quality-adjusted life-years; with an incremental cost-effectiveness ratio of £65,163 per quality-adjusted life-year gained. Shockwave lithotripsy has a 99.9% chance of being cost-effective at a £20,000 threshold value. RCT2: Flexible ureteroscopic stone treatment is more costly (£733; 95% confidence interval -£508 to £1973) and produces fewer quality-adjusted life-years (-0.001; 95% confidence interval -0.044 to 0.042). Keyhole surgery has an 87% chance of being cost-effective at a £20,000 threshold value. Limitations:Blinding of participants and healthcare providers was not possible. There were differential waiting times between interventions in RCT1; however, adjusting for this gave similar treatment effect estimates. Conclusions:The PUrE study found in RCT1 that shockwave lithotripsy was more cost-effective than flexible ureteroscopic stone treatment, with no meaningful difference in patient health status even though complete stone-free rates were higher with flexible ureteroscopic stone treatment. In RCT2, keyhole surgery was more cost-effective than flexible ureteroscopic stone treatment on a micro-costing basis, which better reflects treatment cost differences to the NHS. Keyhole surgery was marginally beneficial for health status with higher complete stone-free rates. Future work:What effect will suction devices, improvements in laser technology, and intraoperative pressure monitoring have on postoperative pain, quality of life, stone-free rates, complications, and costs of flexible ureteroscopic stone treatment? What effect does miniaturisation of keyhole surgery have on postoperative pain, length of stay, complications, stone-free rates and costs? Trial registration:This trial is registered as ISRCTN98970319. Funding:This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 13/152/02) and is published in full in Health Technology Assessment; Vol. 29, No. 40. See the NIHR Funding and Awards website for further award information.

Abstract Background Lymphatic leaks are associated with significant mortality and morbidity. Intranodal lymphangiography (ILAG) involves the direct injection of ethiodised lipid into the hilum of lymph nodes. It is diagnostic procedure that can have therapeutic effects secondary to a local sclerosant effect. The aim of the study is to describe the technical and clinical success of ILAG and adjunctive lymphatic interventions performed as first line interventional techniques for lymphatic leaks refractory to conservative and medical management in a multicentre cohort of patients with symptomatic large volume lymphatic leaks. Methods Multicentre retrospective study of all lymphatic interventions performed between 2017–2023 in patients with large volume lymphatic leaks (> 500 ml a day). Intranodal lymphangiography was performed initially with technical success defined as opacification of the lymphatics at the aortic bifurcation and demonstration of lymphatic leak on the index ILAG procedure or immediate post procedural CT was recorded. Lymphatic embolisation was performed with a combination of direct puncture or transvenous cannulation with glue and or coil embolisation of the thoracic duct or leak point and in cases with refractory leak. Clinical success was defined as reduction in drain output to less than 20 mL per 24 h, or no further insensible lymph leak. Time to clinical success after ILAG and adjunctive embolisation was recorded. Results ILAG alone lead to clinical success in 14 of 32 (44%) patients after a median of 14 days. Subsequent embolisation was performed in 12 refractory cases; this was successful in 8 (67%) at median of 8 days. Overall clinical success of all lymphatic interventions was 69% (22 of 32 patients) at a median of 11 days (IQR 5–34). No statistically significant correlation between the site of leakage, aetiology or embolisation technique correlated with clinical success. Decision to proceed to repeat ILAG or an adjunct procedure was made on a clinical basis, following multidisciplinary discussion. Conclusions ILAG can be employed a first line interventional therapeutic technique to treat clinically significant lymphatic leaks that are refractory to conservative and medical management. Adjunctive procedures, including embolisation, can be considered as part of clinical decision making after a period of 1–2 weeks’ watchful waiting in continuingly refractory cases.

BACKGROUND AND OBJECTIVE:The European Association of Urology guidelines for lower-pole stones (LPS) recommend percutaneous nephrolithotomy (PCNL) for stones >20 mm, flexible ureterorenoscopy (FURS) or PCNL for stones of 10-20 mm if there are unfavourable factors for extracorporeal shockwave lithotripsy (ESWL), or any of these options for stones of 10-20 mm if there are no unfavourable factors for ESWL. PUrE RCT 2 was a pragmatic multicentre, open-label, superiority, randomised controlled trial comparing FURS versus PCNL in terms of quality of life, clinical effectiveness, and cost effectiveness for patients with LPS of 10-25 mm. METHODS:A total of 159 adults with LPS of 10-25 mm were randomised, 73 to FURS and 86 to PCNL. The primary outcome was health status area under the curve (AUC) measured weekly using the EQ-5D-5L questionnaire up to 12 wk after intervention. The primary economic outcome was the incremental cost per quality-adjusted life year (QALY) gained at 12 mo from randomisation. KEY FINDING AND LIMITATIONS:Mean health status AUC slightly favoured PCNL (difference -0.07, 95% confidence interval [CI] -0.11 to -0.02) when adjusted for baseline status. The complete stone clearance rate was higher with PCNL (71%) than with FURS (48%). PCNL was less costly (adjusted mean difference £733, 95% CI -£508 to £1973) and resulted in greater QALYs (adjusted mean difference -0.001, 95% CI -0.044 to 0.042). At a threshold value of £20 000 per QALY, PCNL has an 87% chance of being cost-effective. CONCLUSIONS AND CLINICAL IMPLICATIONS:Results from PUrE RCT 2 show that PCNL resulted in marginally better health status and a higher stone-free rate and was more cost-effective than FURS among patients with LPS of 10-25 mm. These outcomes are important for patient counselling and joint decision-making on LPS treatment.

Background The stone burden based management strategy reported in the guidelines published by different associations is well known for a long time. Staghorn calculi, representing the largest burden and most complex stones, is one of the most challenging cases to practicing urologists in clinical practice. The International Alliance of Urolithiasis (IAU) has released a series of guidelines on the management of urolithiasis. Purpose To develop a series of recommendations for the contemporary management management of staghorn calculi and to provide a clinical framework for urologists treating patients with these complex stones. Methods A comprehensive literature search for articles published in English between 01/01/1976 and 31/12/2022 in the PubMed, OVID, Embase and Medline database is performed. A series of recommendations are developed and individually graded following the review of literature and panel discussion. Results The definition, pathogenesis, pathophysiology, preoperative evaluation, intraoperative treatment strategies and procedural advice, early postoperative management, follow up and prevention of stone recurrence are summarized in the present document. Conclusion A series of recommendations regarding the management of staghorn calculi, along with related commentary and supporting documentation offered in the present guideline is intended to provide a clinical framework for the practicing urologists in the management of staghorn calculi.