First prospective clinical assessment of the ILY® robotic flexible ureteroscopy platform.

PURPOSE: To present the initial prospective clinical assessment of the ILY® robotic ureteroscopy manipulator platform, focusing on its safety and effectiveness. METHODS AND MATERIALS: Data gathered from 31 kidney units which underwent elective robotic flexible ureteroscopy (FURS) for renal stone management utilizing the ILY® robotic system. Patient demographics, stone characteristics, surgical durations, perioperative and post-operative complications, and follow-up parameters were collected. Our primary outcome was evaluating the efficacy and safety of the ILY® robotic ureteroscopy for treating kidney stones. Therefore, we analyzed complication rates, surgical durations, and the stone-free rate during follow-up. RESULTS: Our cohort consisted of 29 patients, presenting with 45 stones with a median volume of 736.22 mm3. The median operation time was 85 min, accompanied by 3 min for robot draping, 3.5 min for robot docking, 48 min of console operation, and lasing time of 36.75 min. Post operative stay for all patients was 1 day, while complications were observed in 9.68% of cases. Notably, all complications were classified as CVD (Clavien-Dindo) class 1 due to pain requiring emergency department visit. The stone-free rate achieved was 93.55%, and none of the patient required reoperation for the treated stone. CONCLUSION: In the first prospective clinical experience of the ILY® robotic FURS, we demonstrated its efficacy and safety. To further investigate its clinical practical value, additional investigations are warranted, including direct comparative analyses with manual flexible ureteroscopy techniques.

Single use flexible ureteroscopes: a review of current technologies and cost effectiveness analysis.

PURPOSE OF REVIEW: Flexible ureteroscopy (fURS) has evolved into both diagnostic and therapeutic modalities. Our review discusses the cost-effectiveness of single use flexible ureteroscopes (su-fURS) and the use of these instruments in routine urological practice. RECENT FINDINGS: There are studies which support the use of su-fURS with an argument of both cost and clinical utility over reusable flexible ureteroscopes (ru-fURS). However, the cost may vary across countries, hence is difficult to compare the results based on the current literature. Perhaps therefore there is a role for hybrid strategy incorporating ru- and su-fURS, where su-fURS are employed in complex endourological cases with a high risk of scope damage or fracture to preserve ru-fURS, with the ability to maintain clinical activity in such an event. SUMMARY: While there seems to be some cost advantages with su-fURS with reduced sterilization and maintenance costs, the data supporting it is sparse and limited. This choice of scope would depend on the durability of ru-fURS, procedural volumes, limited availability of sterilization units in some centers and potential risk of infectious complications. It is time that cost-benefit analysis is conducted with defined outcomes for a given healthcare set-up to help with the decision making on the type of scope that best serves their needs.

In Pursuit of the Optimal Dusting Settings with the Thulium Fiber Laser: An In Vitro Assessment.

Objective: Low energy and high frequency settings are used in stone dusting for holmium lasers. Such settings may not be optimal for thulium fiber laser (TFL). With the seemingly endless combination of settings, we aim to provide guidance to the practicing urologists and assess the efficiency of the TFL platform in an automated in vitro "dusting model." Materials/Methods: Three experimental setups were designed to investigate stone dusting produced by an IPG Photonics TLR-50 W TFL system using 200 µm fiber and soft BegoStone phantoms. The most popular 10 and 20 W dusting settings among endourologist familiar with TFL were evaluated. We directly compared short pulse (SP) vs long pulse (LP) mode using various combinations of pulse energy (Ep) and pulse frequency (F). Thereafter, we tested the 10 and 20 W settings and compared them among each other to elucidate the most efficient settings at each power. Treatments were performed under the same total laser energy delivered to the stone at four different standoff distances (SDs) with a clinically relevant scanning speed of either 1 or 2 mm/sec. Ablation volumes were quantified by optical coherence tomography to assess stone dusting efficiency. Fragment size after ablation at different pulse energies was evaluated by sieving and evaluating under a microscope after treatment. Results: Overall, SP provided greater ablation volume when compared with LP. Our dusting efficiency model demonstrated that the maximum stone ablation was achieved at the combination of high energy/low frequency settings (p < 0.005) and at a SD of 0.2 mm. At all tested pulse energies, no stone phantoms were broken into fragments >1 mm. Conclusions: During stone dusting with TFL, SP offers superior ablation to LP settings. Optimal dusting at clinically relevant scanning speeds of 1 and 2 mm/sec occurs at high energy/low frequency settings. Thulium lithotripsy with high Ep does not result in increased fragment size.

The Financial Burden of Nephrolithiasis and Predictors of Disease-specific Financial Toxicity.

OBJECTIVE: To characterize stone-related financial toxicity among US adults with kidney stones through validated questionnaires for financial toxicity and disease-specific health-related quality of life. MATERIALS AND METHODS: We performed a cross-sectional survey of adults with kidney stone disease from the general population ascertained through a national registry of volunteers (ResearchMatch). A computer-based survey queried stone event history and related costs for medical care, disease-specific quality of life (WISQOL), and an 11-item measure of stone-related financial toxicity (COST-11 score). Multivariable logistic regression was performed to evaluate predictors of financial toxicity, defined as having a COST-11 score ≤20. RESULTS: Of 942 responses, median COST-11 score was 29 (IQR 21-38), and 24.7% (N = 233) met criteria for disease-specific financial toxicity. Stone-formers with financial toxicity spent more out of pocket on stone-treatment in the previous year than patients with lower financial burden (P <.001) and were more likely to defer or delay recommended treatment due to anticipated cost (27% vs 3%; P <.001). Stone-specific financial toxicity was associated with poorer disease-specific health-related quality of life across all WISQOL domains (each P <.001). Multivariable logistic regression showed that female gender (OR 1.81; 95% CI 1.24-2.67), Medicaid compared to private insurance (OR 3.91; 95% CI 2.34-6.94), and stone passage in the previous year (OR 2.00; 95% CI 1.41-2.86) were independently associated with financial toxicity. CONCLUSION: Approximately 1 in 4 individuals with kidney stone disease report disease-specific financial toxicity. These data suggest the financial burden of the condition may influence decision-making and associates with poorer disease-specific quality of life.

Improving Access and Quality of Care for Kidney Stone Patients in an Underserved Community.

There is a call to improve Medicaid patient access to health care, enhance quality and outcomes of care, and reduce overall financial burden. We sought to build a comprehensive kidney stone program to help patients navigate through the acute and preventive aspects of stone disease by increasing multidisciplinary referrals and compliance with recommendations and decreasing no-show rates at first follow-up and repeat stone encounters after initial evaluation. A collaborative multidisciplinary program was established at our single institution consisting of urology, nephrology, and dietary specialists to be piloted over a 3-year period. Medicaid-designated patients were evaluated during new patient encounters by urology specialists and then followed for outpatient follow-up, including specialty referrals to nephrology specialists and dietitians, for targeted preventive measures. Subjective compliance reports by patients following interventions and no-show rates at subsequent follow-ups were documented. We also followed patients 6 months beyond the initial encounter to assess repeat Emergency Department (ED) visits for acute stone episodes. One hundred eighty-three Medicaid-designated stone patients were evaluated from 2018 to 2021. Sixty-eight percent of patients identified as White, 18% identified as Black/African American, and 14% identified as "Other." Patients underwent specialty referrals to nephrology or a dietician in 47% and 42% of cases, respectively. Since the program's implementation, reported patient compliance and referrals to multidisciplinary specialists increased from 72.9% to 81.30% and 21.2% to 56.20%, respectively. Repeat ED visits for stone-related encounters within 6 months of initial presentation remained relatively stable (from 17.60% to 18.9%), while no-show rates at first follow-up decreased from 20.0% to 6.30% by study conclusion. There is continued supporting evidence for the importance of a comprehensive kidney stone program specifically for patients of lower socioeconomic status following a 3-year implementation at our institution. Encouraging results indicate increased access to multidisciplinary specialty referrals, with improvement in follow-up and reported compliance related to stone prevention strategies.

Financial Toxicity of Nephrolithiasis: The First Assessment of the Economic Stresses of Kidney Stone Treatment.

OBJECTIVE: To investigate the financial toxicity (FT) related to kidney stone treatment. METHODS: We performed a cross-sectional cohort study with multi-institutional in-person and online cohorts of stone formers.  Participants were surveyed using the validated COST tool (COmprehensive Score for financial Toxicity). The maximum score is 44 and lower scores indicate increased FT. "Moderate FT" was defined by COST scores between 25 and 14 points and "severe FT" for scores <14. Descriptive statistics, X2 tests, T tests, Spearman correlation, and logistic regression were performed using SPSS v28. RESULTS: Two hundred and forty-one participants were surveyed, including 126 in-person participants and 115 online. A total of 60% of participants reported at least moderate FT (COST score <26) and 26% reported severe FT (COST score <14). Patients who reported moderate to severe FT were younger than those with low FT by a median difference of 8 years (95%CI = 4, 12). There was a significant correlation between out-of-pocket expense and COST scores, such that as out-of-pocket expenses increased, COST scores decreased, (Spearman's rho =-0.406, P = <.001). Participants with moderate to severe FT tended to miss more workdays (P = .002), and their caretakers tended to miss more workdays (P = .007) due to their stone disease. CONCLUSION: Most participants reported moderate to severe FT. As prior studies have shown that patients with "moderate FT" employ cost-coping strategies (i.e., medication rationing) and those with "severe FT" have worse health outcomes, urologists need to be sensitive to the financial burdens of treatment experienced by such patients undergoing kidney stone treatment.

The impact of heat on kidney stone presentations in South Carolina under two climate change scenarios.

The risk of kidney stone presentations increases after hot days, likely due to greater insensible water losses resulting in more concentrated urine and altered urinary flow. It is thus expected that higher temperatures from climate change will increase the global prevalence of kidney stones if no adaptation measures are put in place. This study aims to quantify the impact of heat on kidney stone presentations through 2089, using South Carolina as a model state. We used a time series analysis of historical kidney stone presentations (1997-2014) and distributed lag non-linear models to estimate the temperature dependence of kidney stone presentations, and then quantified the projected impact of climate change on future heat-related kidney stone presentations using daily projections of wet-bulb temperatures to 2089, assuming no adaptation or demographic changes. Two climate change models were considered-one assuming aggressive reduction in greenhouse gas emissions (RCP 4.5) and one representing uninibited greenhouse gas emissions (RCP 8.5). The estimated total statewide kidney stone presentations attributable to heat are projected to increase by 2.2% in RCP 4.5 and 3.9% in RCP 8.5 by 2085-89 (vs. 2010-2014), with an associated total excess cost of ~ $57 million and ~ $99 million, respectively.

Outcomes and costs of ureteroscopy, extracorporeal shockwave lithotripsy, and percutaneous nephrolithotomy for the treatment of urolithiasis: an analysis based on health insurance claims data in Germany.

PURPOSE: Comparisons of ureteroscopy (URS), extracorporeal shockwave lithotripsy (SWL), and percutaneous nephrolithotomy (PCNL) for urolithiasis considering long-term health and economic outcomes based on claims data are rare. Our aim was to analyze URS, SWL, and PCNL regarding complications within 30 days, re-intervention, healthcare costs, and sick leave days within 12 months, and to investigate inpatient and outpatient SWL treatment as the latter was introduced in Germany in 2011. METHODS: This retrospective cohort study based on German health insurance claims data included 164,203 urolithiasis cases in 2008-2016. We investigated the number of complications within 30 days, as well as time to re-intervention, number of sick leave days and hospital and ambulatory health care costs within a 12-month follow-up period. We applied negative binomial, Cox proportional hazard, gamma and two-part models and adjusted for patient variables. RESULTS: Compared to URS cases, SWL and PCNL had fewer 30-day complications, time to re-intervention within 12 months was decreased for SWL and PCNL, SWL and PCNL were correlated with a higher number of sick leave days, and SWL and particularly PCNL were associated with higher costs. SWL outpatients had fewer complications, re-interventions and lower costs than inpatients. This study was limited by the available information in claims data. CONCLUSION: URS cases showed benefits in terms of fewer re-interventions, fewer sick leave days, and lower healthcare costs. Only regarding complications, SWL was superior. This emphasizes URS as the most frequent treatment choice. Furthermore, SWL outpatients showed less costs, fewer complications, and re-interventions than inpatients.

LITHOSCREEN: a comprehensive screening program and database for the assessment and treatment management of patients with kidney stones.

The aim of the LITHOSCREEN project was to construct a comprehensive screening program and database for recording and assessing the various risk factors for stone-formation in patients with urolithiasis. It is intended for use in Stone Clinics and is now being made available free of charge to researchers in the field who wish to maintain a comprehensive record of their patients' medical histories, demographic backgrounds, lifestyle activities, metabolic abnormalities, biochemical risk of forming stones of various types, diet histories, stone analysis and long-term treatment records. From the recorded data for each patient, the program automatically calculates numerous functions important in the understanding of the clinical and chemical risk factors for stone-formation, including the renal handling of the ions involved, various metabolic functions, the biochemical risk of forming kidney stones (PSF), the Tiselius Indices of the supersaturation of urine with respect to calcium oxalate and calcium phosphate, the projected effects of changing the composition of each patient's urinary composition on the risk of stone recurrence, and a program for analysing the diet of patients. It automatically produces one-page Summaries of each patient's biochemical and dietary records with abnormal values highlighted according to a "traffic-light" colour-coding system and generates charts designed to improve patient compliance with treatment in the form of colour-coded "Target Diagrams" showing (a) the patient's 24-h urine composition, (b) the patient's biochemical risk of forming stones of different types and (c) the composition of the patient's diet. The Summary pages and "Target Diagrams" are suitable for inclusion in the patient's Case Notes. LITHOSCREEN also produces charts projecting the effect of changing the composition of urine on the patient's biochemical risk of forming further stones. These graphs provide clues as to which urinary risk factors to target to reduce the patient's risk of stone recurrence.

[Assessment of radiopaque kidney stone treatment: Combination of extracorporeal shock wave lithotripsy and Fagolitos Plus®. Preliminary case control description.] / Evaluación del tratamiento de litiasis renal radiopaca mediante la combinación de litotricia extracorpórea por ondas de choque y Fagolitos Plus®. Estudio preliminar de casos y controles.

INTRODUCTION: The nutritional supplement called Fagolitos plus® contains hydroxycitric acid as main component, in addition to zinc, magnesium, vitamin A and vitamin B6. It is necessary to study new molecules as chemolytic treatment in calcium lithiasis or that facilitate its fragmentation with the help of other instrumental treatments. OBJECTIVE: The objective of this study is to evaluate the effectiveness of the combined treatment of Fagolitos plus® and extracorporeal lithotripsy in the fragmentation of the lithiasis. MATERIAL AND METHODS: Retrospective case-control study includes 88 patients with lithiasis. Group 1: Treated with 1 session of extracorporeal lithotripsy and Fagoliths plus®. Group 2: Treated with 1 session of extracorporeal lithotripsy. The variables analyzed were: Age, sex, body mass index, maximum diameter of the stone, area of the stone, hounsfield units of the stone measured by axial tomography, location of the stone, result after 1 session of extracorporeal wave lithotripsy shock [complete fragmentation, partial fragmentation (presence of a fragment greater than 5 mm) and absence of fragmentation (same size of the lithiasis)], adverse effects that occurred after taking Fagolitos plus®, days of treatment with Fagolitos plus® and energy shock wave applied to lithiasis. Results were analyzed with SPSS 20.0, p≤0.05. RESULTS: The mean age of the patients included in the study is 53.81 ± 12.62 years in group 1 compared to 56.53 ± 12.37 years in group 2, p=0.31. According to the distribution by sex, there were no statistically significant differences (p=0.5), including 24 men and 24 women in group 1 and 23 men and 17 women in group 2. The mean of body mass index of the patients in group 1 was 28.39 ± 2.27 kg/m2 in group 1 versus 28.39 ± 3.03 kg/m2 in group 2, p=0.9. The maximum diameter of the stone was 11.5 ± 3.91 mm in group 1 compared to 13.15 ± 5.49 mm in group 2, p=0.1. The area of the lithiasis measured by tomography was 104.74 ± 70.56 mm2 in group 1 compared to 141.91 ± 80.95 mm2 in group 2, p=0.3. The Hounsfield units measured by tomography of the lithiasis in group 1 was 1061.98 ± 213.68 compared to 1143.15 ± 172.24 in group 2, p=0.06. Relation to fragmentation, complete fragmentation was observed in 66.7% of group 1 patients, compared to 41% of group 2 patients (p=0.02), between 20-30 days after the first session of Extracorporeal Lithotripsy evaluated by means of a simple X-ray of the Abdomen. CONCLUSIONS: The administration of Fagolitos plus® concomitant to extracorporeal lithotripsy could increase its effectiveness in lithiasis fragmentation, requiring clinical trials and prospective studies to confirm these findings.

INTRODUCCIÓN: El complemento nutricional denominado Fagolitos plus® contiene como principal componente ácido hidroxicítrico, además de zinc, magnesio, vitamina A y vitamina B6. Es necesario estudiar nuevas moléculas como tratamiento quimiolítico en litiasis cálcica o que faciliten su fragmentación con la ayuda de otros tratamientos instrumentales. OBJETIVO: El objetivo de este estudio es evaluar la efectividad del tratamiento combinado de Fagolitos plus® y Litotricia extracorpórea en la fragmentación de la litiasis.MATERIAL Y MÉTODOS: Estudio retrospectivo de casos y controles, incluye 88 pacientes con litiasis. Grupo 1: Tratados con 1 sesión de litotricia extracorpórea y Fagolitos plus®. Grupo 2: Tratados con 1 sesión de litotricia extracorpórea. Las variables analizadas fueron: Edad, sexo, índice de masa corporal, diámetro máximo de la litiasis, área de la litiasis, unidades hounsfield de la litiasis medida por Tomografía axial, localización de la litiasis, resultado tras 1 sesión de Litotricia extracorpórea por ondas de choque [fragmentación completa, fragmentación parcial (presencia de un fragmento mayor a 5 mm) y ausencia de fragmentación (mismo tamaño de la litiasis)], efectos adversos acontecidos tras la toma de Fagolitos plus®, días de tratamiento con Fagolitos plus® y energía de ondas de choque aplicada a la litiasis. Se analizaron resultados con SPSS 20.0, p≤0,05. RESULTADOS: La edad media de los pacientes incluidos en el estudio es de 53,81 ± 12,62 años en el grupo 1 frente a 56,53 ± 12,37 años en el grupo 2, p=0,31. Según la distribución por sexos, tampoco existen diferencias estadísticamente significativas (p=0,5), incluyendo 24 hombres y 24 mujeres en el grupo 1 y 23 hombres y 17 mujeres en el grupo 2. El índice de masa corporal medio de los pacientes del grupo 1 fue de 28,39 ± 2,27 kg/m2 en el grupo 1 frente a 28,39 ± 3,03 kg/m2 en el grupo 2, p=0,9. El diámetro máximo de la litiasis fue de 11,5 ± 3,91 mm en el grupo 1 frente a 13,15 ± 5,49 mm en el grupo 2, p=0,1. El área de la litiasis medida por tomografía computarizada fue de 104,74 ± 70,56 mm2 en el grupo 1 frente a 141,91 ± 80,95 mm2 en el grupo 2, p=0,3. Las unidades Hounsfield medidas por tomografía de la litiasis en el grupo 1 fue de 1061,98 ± 213,68 frente a 1143,15 ± 172,24 en el grupo 2, p=0,06. En relación con la fragmentación, se observó fragmentación completa en el 66,7% de los pacientes del grupo 1, frente al 41% de los pacientes del grupo 2 (p=0,02) entre 20-30 días tras la primera sesión de Litotricia Extracorpórea evaluado mediante Radiografía simple de Abdomen. CONCLUSIONES: La administración de Fagolitos plus® concomitante a la Litotricia extracorpórea podría aumentar su efectividad en la fragmentación de la litiasis, siendo necesarios ensayos clínicos y estudios prospectivos que confirmen estos hallazgos.

Comparing extracorporeal shock wave lithotripsy and ureteroscopy laser lithotripsy for treatment of urinary stones smaller than 2 cm: a cost-utility analysis in the Spanish clinical setting.

PURPOSE: To analyze the efficiency and cost-utility profile of ureteroscopy versus shock wave lithotripsy for treatment of reno-ureteral stones smaller than 2 cm. METHODS: Patients treated for urinary stones smaller than 2 cm were included in this study (n = 750) and divided into two groups based on technique of treatment. To assess the cost-utility profile a sample of 48 patients (50% of each group) was evaluated. Quality of life survey (Euroqol 5QD-3L) before-after treatment was applied, Markov model was designed to calculate quality of life in each status of the patients (stone or stone-free with and without double-J stent) and to estimate the incremental cost-utility. Monte carlo simulation was conducted for a probabilistic sensitivity analysis. Chi-square was used for comparing qualitative variables and T student's for continuous variables. RESULTS: Shock wave lithotripsy group had 408 (54.4%) and ureteroscopy group had 342 (45.6%) patients. Of them, 56.3% were treated for renal stones and 43.7% for ureteral stones. Ureteroscopy produced slightly higher overall quality of patients' life, but produced a significant higher overall cost per quality-adjusted life year (QALY) than shock wave lithotripsy, exceeding the cost-utility threshold (20,000€/QALY). Sensitivity analysis confirmed results in 93.65% of cases. Difference was maintained in subgroup analysis (ureteral vs renal stones). CONCLUSIONS: Results suggest that in our clinical setting shock wave lithotripsy has better cost-utility profile than ureteroscopy for treatment of reno-ureteral stones less than 2 cm, but excluding waiting times, in ideal clinical setting, ureteroscopy would have better cost-utility profile than shock wave lithotripsy.

Lessons Learnt (Clinical Outcomes and Cost Savings) from Virtual Stone Clinic and Their Application in the Era Post-COVID-19: Prospective Outcomes over a 6-Year Period from a University Teaching Hospital.

Introduction: We introduced a nurse-led telephone-based virtual stone clinic (VSC) follow-up for the surveillance of patients with asymptomatic renal calculi or those at a high risk of recurrent kidney stone disease (KSD). The aim of this study was to look at the outcomes of VSC and its role in the post-COVID era. Methods: Prospective outcomes audit was done for all patients referred to the VSC for a 6-year period (March 2014-April 2020). VSC is led by specialist stone nurses for on-going surveillance of KSD patients. Results: A total of 290 patients were seen (468 individual appointments; 1.6 ± 1.0 per patient), with a mean age of 57.0 ± 15.8 years (range: 17-92) and a men-women ratio of 3:2. The referral was for surveillance of asymptomatic small renal stones (230, 79.3%); history of recurrent stone disease (45, 15.5%); solitary kidneys (5, 1.7%); cystine stones; young age; and other conditions (10, 3.4%). The mean stone size was 5.0 ± 2.7 mm, followed up with kidney, ureter, and bladder radiograph (225, 77.6%) and ultrasound scan (USS) (65, 22.4%), for median duration of 12 months (range: 3-24 months). At the end, 132 patients (45.6%) remained in VSC, 106 (36.6%) were discharged, 47 (16.2%) returned to face-to-face clinic or treatment, and 5 (1.7%) had emergency admissions. Of 47 patients who returned, 23 (48.9%) developed new symptoms, 21 (44.6%) had stone growth, and 3 defaulted to face-to-face appointment. Thirty-five patients needed surgical intervention (URS-21, SWL-13, and PCNL-1) and 10 were managed conservatively. VSC reduced the cost per clinic appointment from £27.9 to £2 per patient (93% reduction), equating to a total saving of £12,006 for the study period. Conclusion: Nurse-led VSC not only provided a safe follow-up but also allowed to substantially reduce the cost of treatment by allowing patients to be either discharged or return to a face-to-face clinic or surgical intervention if needed. Post-COVID, this model using telemedicine will have a much wider uptake and further help to optimize health care resources.

Systematic Evaluation of Smartphone Applications for the Medical Management of Nephrolithiasis.

Objective: The aim of this study was to comprehensively evaluate the quality of patient-oriented, mobile health applications (apps) available for medical management of kidney stone disease (KSD). Materials and Methods: A systematic search was performed to identify apps from the Apple and Google Play app stores. Eligible apps were divided into two categories: (1) fluid apps and (2) dietary apps. Descriptive characteristics were summarized and app quality was independently evaluated on the basis of technical quality, usability, clinical value, and privacy/security. The validated Mobile App Rating Scale (MARS) was the backbone for the evaluation framework. Results: In total, 31 apps (18 fluid apps and 13 dietary apps) were included. Fluid apps outscore dietary apps in all dimensions of MARS quality. All but one fluid app exceeded the minimum acceptable MARS score of 3.0 vs 46% of dietary management apps. Dietary apps feature less functionality and most are limited to noninteractive informational content. While most data-capturing apps provide a privacy policy and ensure that security measures are taken to protect user identity, only 36% offer users choice or consent for secondary use of their data after data have already been collected. Overall, only one app has undergone any form of real-world clinical investigation. Conclusions: Fluid management apps outperform dietary apps in technical quality, usability, and clinical value at the cost of greater privacy/security risks. Despite not being targeted to patients with KSD, they are higher in most quality measures and offer greater functionality to support long-term disease management compared with dietary apps.

Novel prediction scoring system for simple assessment of stone-free status after flexible ureteroscopy lithotripsy: T.O.HO. score.

OBJECTIVES: To develop a novel simple quantitative scoring model for predicting stone-free status after a flexible ureteroscopy lithotripsy procedure by standardizing the complexity of ureteral stone characteristics. METHODS: We retrospectively reviewed 586 patients with renal or ureteral stones who underwent flexible ureteroscopy lithotripsy at Abiko Toho Hospital, Chiba, Japan, from 2015 to 2018. Multivariate regression was applied to examine the relationship between preoperative descriptors and stone-free status, and a nomogram was developed using significant predictors. Next, the individual components of the nomogram were assigned points to form a simple scoring system. The predictive performance of this new scoring system was compared with the STONE score at optimal cut-off values using receiver operating characteristic curve and area under the curve analyses. RESULTS: Multivariate logistic regression findings showed that factors associated with stone-free status were length, Hounsfield unit and stone location. A nomogram prediction model was developed with an area under the curve value of 0.845, then consequently used to develop a new simple score system termed the T.O.HO. score consisting of three stone characteristics: (T)allness (1-5 points), (O)ccupied lesion (1-3 points) and (HO)unsfield units evaluation (1-3 points). The T.O.HO. score was significantly higher in stone remaining (7.66) than stone-free (5.27; P < 0.001) cases. The area under the curve for the T.O.HO. score was 0.833 at an optimal cut-off value of 7, whereas that for the STONE score was 0.683 at an optimal cut-off value of 9, showing the superiority of this new scoring system. CONCLUSION: The T.O.HO. score is a useful tool for predicting stone-free status in patients who have undergone a flexible ureteroscopy lithotripsy procedure.

Racial Differences in Risk Factors for Kidney Stone Formation.

BACKGROUND AND OBJECTIVES: Incidence of kidney stone disease is rising. It is not known whether mechanisms of stone formation differ across racial groups. Our objective was to identify differing lithogenic risk factors across racial groups in idiopathic nephrolithiasis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a retrospective cohort study evaluating metabolic risk factors in black and age-matched white idiopathic stone formers at our tertiary referral center. We compared serum and urine metabolic risk factors pre- and post-treatment across racial groups using analysis of covariance. Generalized linear modeling was used to build regression models for risk of stone formation in both groups. RESULTS: Among 117 black and 172 white stone formers, urine volume was lower in black stone formers (1.4±0.8 versus 2.0±0.8 L/d, P<0.001). Urine calcium was lower in black stone formers (116±70 versus 217±115 mg/d, P<0.001). Supersaturations for calcium oxalate were similar among the groups, whereas calcium phosphate supersaturation was higher in white stone formers, and uric acid supersaturation was higher in black stone formers. Electrolyte free water clearance was significantly lower in black stone formers (207±780 versus 435±759 ml/d, P=0.02). In the subgroup of 77 black patients and 107 white patients with post-treatment evaluations, urine volume rose significantly and similarly in both groups. Urine sodium was unchanged in whites but increased in blacks by 40 mmol/d (95% confidence interval, 32 to 48 mmol/d). Electrolyte free water clearance remained lower in black stone formers (385±891 versus 706±893 ml/d, P=0.02). Post-treatment supersaturations were similar across the groups except for calcium phosphate, which improved with treatment in whites. CONCLUSIONS: Black stone formers have lower 24-hour urine calcium excretion and urine volume. Increases in urine volume with treatment were associated with increased solute, but not free water, excretion in black stone formers.

The Association Between 24-Hour Urine and Stone Recurrence Among High Risk Kidney Stone Formers: A Population Level Assessment.

OBJECTIVE: To determine if obtaining a 24-hour urine collection (24HU) in stone formers is associated with decreased recurrent stone episodes. METHODS: Using the MarketScan database, adults 17-62 years old with nephrolithiasis were identified between 2007 and 2017 with a minimum of 3-year follow up. High-risk stone formers, those undergoing stone surgery, and those with history of recurrent stones were identified. The exposure was a 24HU within 6 months of primary diagnosis. The outcome was recurrent stone episodes-defined by stone-related emergency room visits, hospitalizations, or stone surgery 90 days to 3 years after diagnosis. Logistic regression was used to estimate recurrence risk by 24HU exposure for the overall cohort and sub-cohorts limited to known recurrent stone formers, high-risk subjects, and those having stone surgery. RESULTS: Of 434,055 subjects analyzed, 30,153 (6.9%) had a 24HU. An annual decline in 24HU utilization was seen (7.5%-5.8%). Regional variation in usage rate was also observed. On multivariate analysis, completing a 24HU was not associated with risk of recurrence in any of the following cohorts: recurrent stone formers (OR 0.98, 95% CI 0.9-1.07), both high risk and recurrent stone formers (OR 0.95 [0.8-1.13]), those undergoing surgery (OR 1.02 [0.97-1.07]); a positive association with 24HU and recurrence was seen in those labeled high-risk (OR 1.08 [1.01-1.16]) and in all-comers (OR 1.15 [1.12-1.19]). CONCLUSION: The 24HU was not associated with decreased recurrence rates in the overall population nor in higher risk sub-cohorts.

The clinical and cost effectiveness of surgical interventions for stones in the lower pole of the kidney: the percutaneous nephrolithotomy, flexible ureterorenoscopy and extracorporeal shockwave lithotripsy for lower pole kidney stones randomised controlled trial (PUrE RCT) protocol.

INTRODUCTION: Renal stones are common, with a lifetime prevalence of 10% in adults. Global incidence is increasing due to increases in obesity and diabetes, with these patient populations being more likely to suffer renal stone disease. Flank pain from stones (renal colic) is the most common cause of emergency admission to UK urology departments. Stones most commonly develop in the lower pole of the kidney (in ~35% of cases) and here are least likely to pass without intervention. Currently there are three technologies available within the UK National Health Service to remove lower pole kidney stones: extracorporeal shockwave lithotripsy (ESWL), percutaneous nephrolithotomy (PCNL) and flexible ureterorenoscopy (FURS) with laser lithotripsy. Current evidence indicates there is uncertainty regarding the management of lower pole stones, and each treatment has advantages and disadvantages. The aim of this trial is to determine the clinical and cost effectiveness of FURS compared with ESWL or PCNL in the treatment of lower pole kidney stones. METHODS: The PUrE (PCNL, FURS and ESWL for lower pole kidney stones) trial is a multi-centre, randomised controlled trial (RCT) evaluating FURS versus ESWL or PCNL for lower pole kidney stones. Patients aged ≥16 years with a stone(s) in the lower pole of either kidney confirmed by non-contrast computed tomography of the kidney, ureter and bladder (CTKUB) and requiring treatment for a stone ≤10 mm will be randomised to receive FURS or ESWL (RCT1), and those requiring treatment for a stone >10 mm to ≤25 mm will be randomised to receive FURS or PCNL (RCT2). Participants will undergo follow-up by questionnaires every week up to 12 weeks post-intervention and at 12 months post-randomisation. The primary clinical outcome is health status measured by the area under the curve calculated from multiple measurements of the EuroQol five dimensions five-level version (EQ-5D-5L) questionnaire up to 12 weeks post-intervention. The primary economic outcome is the incremental cost per quality-adjusted life year gained at 12 months post-randomisation. DISCUSSION: The PUrE trial aims to provide robust evidence on health status, quality of life, clinical outcomes and resource use to directly inform choice and National Health Service provision of the three treatment options. TRIAL REGISTRATION: ISRCTN: ISRCTN98970319. Registered on 11 November 2015.

Regional Variation in Shock Wave Lithotripsy Utilization Among Medicare Patients with Nephrolithiasis.

OBJECTIVE: To characterize shock wave lithotripsy (SWL) utilization and assess for regional variation in the use of this procedure across the United States. MATERIALS AND METHODS: We examined SWL and URS utilization among Medicare Beneficiaries with a diagnosis of nephrolithiasis for the years 2006, 2009, and 2014. Adjusted utilization rates were calculated per 1000 beneficiaries accounting for age, sex, and race. Utilization rates were examined nationally and by hospital referral region (HRR). RESULTS: A total of 511,495, 604,493, and 806,652 Medicare beneficiaries had a diagnosis of nephrolithiasis in 2006, 2009, and 2014, respectively. The adjusted rate of SWL per 1000 beneficiaries with nephrolithiasis decreased from 59.4/1000 in 2006 to 52.2/1000 and 45.5/1000 in 2009 and 2014 (13.9% decrease, P < .001). Variation was observed in SWL utilization; up to a 12-fold difference between HRRs (9.2/1000 in Winchester, VA to 105.8/1000 in Lincoln, NE). The adjusted rate of URS per 1000 beneficiaries increased by 10.2% (P < .001) between 2006 and 2014. However, the percent decrease in SWL utilization did not correlate with the percent increase in URS utilization when examined by HRR (P = .66). CONCLUSION: Variation exists in the utilization of SWL among Medicare beneficiaries (12-fold difference). This variation is likely secondary to a series of supply, urologist, and patient-specific factors. SWL utilization decreased between 2006 and 2014, while URS increased. Stone procedure type is likely highly dependent on where patients receive their urologic care.

Quantitative Assessment of Effectiveness of Ultrasonic Propulsion of Kidney Stones.

Purpose: Ultrasonic propulsion is an investigative modality to noninvasively image and reposition urinary stones. Our goals were to test safety and effectiveness of new acoustic exposure conditions from a new transducer, and to use simultaneous ureteroscopic and ultrasonic observation to quantify stone repositioning. Materials and Methods: During operation, ultrasonic propulsion was applied transcutaneously, whereas stone targets were visualized ureteroscopically. Exposures were 350 kHz frequency, ≤200 W/cm2 focal intensity, and ≤3-second bursts per push. Ureteroscope and ultrasound (US) videos were recorded. Video clips with and without stone motion were randomized and scored for motion ≥3 mm by independent reviewers blinded to the exposures. Subjects were followed with telephone calls, imaging, and chart review for adverse events. Results: The investigative treatment was used in 18 subjects and 19 kidneys. A total of 62 stone targets were treated ranging in size from a collection of "dust" to 15 mm. Subjects received an average of 17 ± 14 propulsion bursts (per kidney) for a total average exposure time of 40 ± 40 seconds. Independent reviewers scored at least one stone movement ≥3 mm in 18 of 19 kidneys (95%) from the ureteroscope videos and in 15 of 19 kidneys (79%) from the US videos. This difference was probably because of motion out of the US imaging plane. Treatment repositioned stones in two cases that would have otherwise required basket repositioning. No serious adverse events were observed with the device or procedure. Conclusions: Ultrasonic propulsion was shown to be safe, and it effectively repositioned stones in 95% of kidneys despite positioning and access restrictions caused by working in an operating room on anesthetized subjects.