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Introduction and Objective: In early 2020, as the SARS-Cov-2 (COVID-19) pandemic progressed, many institutions limited nonurgent surgical care. This coincided with a decade-long trend of increasing percutaneous nephrolithotomy (PCNL) and ureteroscopy (URS) and decreasing shock wave lithotripsy (SWL) for surgical management of urolithiasis. Herein, we evaluate temporal stone surgery rates and surgeon volumes in the Medicare population and suggest how COVID-19 contributed to them. Methods: Retrospective analysis was conducted using the "Medicare Physician & Other Practitioners" database containing data from January 2013 to December 2021. Adult patients who underwent stone surgery were included. We evaluated surgeon characteristics and changes in case volumes over time adjusted for population. Results: In 2013, urologists performed 68,910 stone surgeries: SWL 42,903 (62%); URS 25,321 (37%); PCNL 686 (1%). Over the next 8 years, there was an average annual increase in URS (+13%) and PCNL (+13%) and decrease in SWL (-2%). In 2020, there was a 14% reduction in all stone cases: SWL (-25%); URS (-6%); PCNL (-8%). By 2021, case volumes recovered to pre-2020 levels, though SWL remained low: SWL 33,974 (34%); URS 64,541 (64%); PCNL 1764 (2%). From 2013 to 2021, the number of urologists performing SWL decreased (1718 to 1361) while URS and PCNL providers doubled (1,347 to 2,914 and 28 to 76, respectively). Conclusions: From 2013 to 2021, there was an increase in URS and PCNL and a decrease in SWL in the US Medicare population. The COVID-19 pandemic was associated with a decline in stone surgeries, particularly SWL. By 2021, PCNL and URS case numbers increased significantly with a smaller increase in SWL.

Objective: To identify the need for repeat stone surgery in patients with and without bowel disease. Few studies have compared risks between different types of bowel disease and whether their need for repeat stone surgery differs., Methods: From our IRB-approved study, we identified patients with and without bowel disease. We categorized patients' bowel disease into 4 categories: inflammatory bowel disease (IBD), bypass procedures, bowel resection, and bowel disease not otherwise specified (eg, irritable bowel syndrome, celiac disease). Differences between patient demographics, stone disease, and recurrent stone events for patients with and without bowel disease were compared using univariate and multivariate survival analyses (SPSS 25)., Results: Of all surgical stone patients (2011), 484 (24%) had some type of bowel disease. Compared to patients without bowel disease, patients with bowel disease presented with stones at an older age (62.2 ± 14.5 vs 58.4 ± 15.3 years; P <.001) and were more likely to be female (56 vs 46%; P <.001). Patients with bowel disease required more repeat stone surgery than those without bowel disease (31% vs 23%, P <.001). In multivariate analysis, patients with bypass and bowel resection were associated with more repeat surgery than patients without bowel disease (P <.001, P = .002, respectively). Patients with IBD and bowel disease not otherwise specified did not have higher risk for repeat surgery than patients without bowel disease., Conclusion: Surgical stone patients with bowel disease, specifically those with prior bowel resection and bypass, had a higher risk of repeat stone surgery over time than stone formers without bowel disease., Data Availability: The data sets generated and analyzed during the current study are available from the corresponding author on reasonable request., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: To assess the impact of kidney stone disease (KSD) and its treatment on the health-related quality of life (HRQOL) of high-risk stone formers with hyperparathyroidism, renal tubular acidosis, malabsorptive disease, and medullary sponge kidney., Patients and Methods: The Wisconsin Stone Quality of Life questionnaire was used to evaluate HRQOL in 3301 patients with a history of KSD from 16 institutions in North America between 2014 and 2020. Baseline characteristics and medical history were collected from patients, while active KSD was confirmed through radiological imaging. The high-risk group was compared to the remaining patients (control group) using the Wilcoxon rank-sum test., Results: Of 1499 patients with active KSD included in the study, the high-risk group included 120 patients. The high-risk group had significantly lower HRQOL scores compared to the control group (P < 0.01). In the multivariable analyses, medullary sponge kidney disease and renal tubular acidosis were independent predictors of poorer HRQOL, while alkali therapy was an independent predictor of better HRQOL (all P < 0.01)., Conclusions: Among patients with active KSD, high-risk stone formers had impaired HRQOL with medullary sponge kidney disease and renal tubular acidosis being independent predictors of poorer HRQOL. Clinicians should seek to identify these patients earlier as they would benefit from prompt treatment and prevention., (© 2024 The Authors. BJU International published by John Wiley & Sons Ltd on behalf of BJU International.)

Introduction: We examined the history of the Endourological Society through the lens of its fellowship programs in the United States (U.S.). Methods: A review of the list of fellowship programs published annually in the Journal of Endourology from 1987 to 2015 allowed us to track the growth in fellowship programs over time. We reviewed the Endourological Society fellowship database and the websites for each of the fellowship programs for the names of graduates from each program. A survey was sent to each fellowship program director with a list of their graduates asking them to verify the names and to identify those graduates who had pursued a career in academic urology, and whether they had served as fellowship program director, residency program director or department chairperson. Seventeen of the 52 U.S. program directors (33%) responded to the survey. For those programs that did not respond to the survey each graduate's name was searched via Google, LinkedIn, and/or Doximity to determine if they had pursued a career in academic urology and served in a leadership position. Results: The number of U.S. Endourological Society fellowships has increased from 11 in 1987 to 52 in 2021. Five hundred and seventy-seven fellows have graduated from an Endourological Society Fellowship in the United States from 1987 to 2021. Two hundred and fifty fellows have pursued a career in academic urology (43.3%), 46 have served as fellowship program director (8.0%), 9 as residency program director (1.6%), and 13 have served as department chairperson (2.3%). Conclusions: The progress of the Endourological Society can be directly tied to the historical growth of its fellowship programs and the pursuit of an academic career by many of its graduates leading them to become the current and future educational leaders in the field.

Purpose: Patients with recurring kidney stone events can expect significant morbidity and functional impairment. Few studies have evaluated the effect of bilateral kidney stones on disease progression and quality of life. We wanted to determine the association of bilateral stone disease on age of onset, and the impact on number of stone events and individual kidney stone disease-specific health-related quality of life (HRQOL) by analyzing the validated and prospectively collected Wisconsin Stone Quality of Life (WISQOL) database. Materials and Methods: We studied 2906 stone patients from 16 centers in North America after having completed the WISQOL questionnaire from 2014 to 2019. Kidney stone formers were assessed if kidney stones were bilateral or unilateral on imaging. Analysis with a chi-square test compared categorical variables. Bilateral kidney stone disease and its impact on HRQOL were evaluated through a multivariable linear regression model. Results: Of 2906 kidney stone formers, 1340 had unilateral kidney stones and 1566 had bilateral kidney stones. We observed more frequently that patients with bilateral stones had an increased number of depression/anxiety symptoms, renal tubular acidosis, and rheumatoid arthritis (all p  < 0.05). Patients with bilateral stones had a younger mean (standard deviation [SD]) age of kidney stone disease onset (37.2 ± 15.8 vs 46.4 ± 15.9 years of age, p  < 0.001). Bilateral kidney stone formers had a higher mean (SD) number of stone events (11.3 ± 21.8) than unilateral kidney stone formers (3.0 ± 5.1) ( p  < 0.001). Within our multivariable analysis, we found that HRQOL was negatively affected by the presence of bilateral stones for kidney stone patients ( β  = -11.2 [confidence interval: -19.5 to -3.0] points, p  < 0.05). Conclusions: Bilateral kidney stone formers had a younger age of kidney stone disease onset and a higher number of stone events compared with unilateral kidney stone disease formers. The presence of bilateral kidney stone disease negatively impacted HRQOL.

Competing Interests: Declaration of Competing Interest The authors have no conflict of interest to declare.

Purpose: Use deep learning (DL) to automate the measurement and tracking of kidney stone burden over serial CT scans. Materials and Methods: This retrospective study included 259 scans from 113 symptomatic patients being treated for urolithiasis at a single medical center between 2006 and 2019. These patients underwent a standard low-dose noncontrast CT scan followed by ultra-low-dose CT scans limited to the level of the kidneys. A DL model was used to detect, segment, and measure the volume of all stones in both initial and follow-up scans. The stone burden was characterized by the total volume of all stones in a scan (SV) . The absolute and relative change of SV , ( SVA and SVR , respectively) over serial scans were computed. The automated assessments were compared with manual assessments using concordance correlation coefficient (CCC), and their agreement was visualized using Bland-Altman and scatter plots. Results: Two hundred twenty-eight out of 233 scans with stones were identified by the automated pipeline; per-scan sensitivity was 97.8% (95% confidence interval [CI]: 96.0-99.7). The per-scan positive predictive value was 96.6% (95% CI: 94.4-98.8). The median SV , SVA , and SVR were 476.5 mm 3 , -10 mm 3 , and 0.89, respectively. After removing outliers outside the 5th and 95th percentiles, the CCC measuring agreement on SV , SVA , and SVR were 0.995 (0.992-0.996), 0.980 (0.972-0.986), and 0.915 (0.881-0.939), respectively Conclusions: The automated DL-based measurements showed good agreement with the manual assessments of the stone burden and its interval change on serial CT scans.

Objective: To develop a short form of the Wisconsin Stone Quality of Life (WISQOL): 1) identify the smallest subset of items from WSIQOL that accurately predict patients' health-related quality of life (HRQOL), and 2) in a clinical patient population, test these items-grouped together to form the WISQOL-short form (SF) - and assess its convergent validity., Materials and Methods: The items for the WISQOL-SF were identified based on classic item analysis theory. Patients who previously completed the original 28-item WISQOL were randomly split into 2 groups of equal size. Scores for the WISQOL were calculated for one group while those for the WISQOL-SF were calculated for the other. Cronbach's alpha coefficients were calculated. Impacts of demographic and clinical factors as well as stone and symptom status at the time of WISQOL completion were examined., Results: Patients (n = 740) who completed the WISQOL between 6/2017 and 11/2021 were included. Patients were 48% male, 54.1 ± 14.6 years old, and had a BMI of 31.2 ± 8.1. After item analysis and reduction, the six items ultimately included in the WISQOL-SF represented 2 of the 4 domains (social and emotional) of the original WISQOL. The internal consistency of the WISQOL-SF was similar to the original (Cronbach's alpha 0.943 vs. 0.973). No differences for health-related quality of life were found between groups (P = .567)., Conclusion: The WISQOL-SF demonstrated the expected differences for gender and between patients with and without stone-related symptoms at the time of WISQOL completion. The WISQOL-SF showed good consistency and produced similar HRQOL scores to the full-form WISQOL., Competing Interests: Declaration of Competing Interest None Declared., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction and Objective: Both ureteroscopy (URS) and shock wave lithotripsy (SWL) are cornerstones in the surgical management of urolithiasis in the United States. We hypothesized that URS utilization outpaced SWL utilization in recent years and quantified the magnitude of change over time for caseloads of URS and SWL among urologists from a national Medicare database. Methods: Using the public "Medicare Physician & Other Practitioners" database (https://data.cms.gov), we determined case numbers of SWL (current procedural terminology [CPT] 50590) and URS (CPT 52356 or 52353) from 2012 to 2019. In a subanalysis, we identified "high-volume stone urologists" as those in the upper quartile of case numbers for both SWL and URS in baseline years of either 2012 or 2013 and trended their caseload from 2012 to 2019. Linear estimation models assessed annual rates of change and their statistical significance. Results: In 2012, urologists performed 41,135 SWL procedures vs 21,184 URS. URS overtook SWL in 2017 and by 2019 was the dominant modality (60,063 URS vs 43,635 SWL). Between 2012 and 2019, total URS cases annually increased by 5700 (15%/year, p  < 0.001), while the number of SWL cases peaked in 2015 and has since declined on average -1.6%/year ( p  = 0.020). The number of urologists performing URS steadily rose from 1147 in 2012 to 2809 in 2019, reflecting an additional 246 urologists (21%/year) performing URS annually. The caseload of high-volume stone urologists showed similar trends with average URS cases increasing by 2.9/year/urologist (9.8%/year, p  < 0.001) and average SWL cases declining by 0.9/year/urologist (-1.7%/year, p  = 0.023). Conclusions: URS utilization has increased dramatically and outpaced SWL utilization from 2012 to 2019 within the Medicare population. URS was increasingly used by both the general urologist population and high-volume stone urologists while SWL utilization has begun to decline.

Purpose: We sought to compare the clinical effectiveness of the pulse-modulated Ho:YAG (holmium:yttrium-aluminum-garnet) laser and the thulium laser fiber for ureteroscopic stone management in a randomized clinical trial. The primary outcome was the ureteroscope time required to adequately fragment stones to 1 mm or less. Secondary outcomes were stone-free rate, complications, subjective surgeon measurement of laser performance, patient related stone quality of life outcomes, and measurements of laser efficiency., Materials and Methods: An Institutional Review Board-approved randomized clinical trial was conducted to randomize patients to outpatient treatment with either the Moses 2.0 or thulium laser fiber in a 1:1 manner after stratification into groups based on the maximal diameter of treated stone (3-9.9 mm or 10-20 mm). Patient, stone, and operative parameters were compared using the appropriate categorical/continuous and parametric/nonparametric statistical tests (SPSS 25)., Results: From July 16, 2021 to March 11, 2022, 108 patients were randomized and had primary endpoint data available for analysis; 52 patients were randomized to Ho:YAG and 56 patients to thulium laser fiber. Groups were well balanced with no significant differences observed for patient or stone characteristics. Ureteroscope time was not significantly different between modalities (Ho:YAG mean 21.4 minutes vs thulium laser fiber mean 19.9 minutes, P = .60), or within subgroup analysis by stone size, median Hounsfield units, or stone location. There were no significant differences observed in the stone-free rate and complications rate between the 2 lasers., Conclusions: This randomized clinical trial suggests no significant clinical advantage of one laser technology over the other. Surgeon and institutional preference are the best approach when selecting one or the other.

Introduction: With a 5-year stone recurrence rate of 30% to 50%, kidney stone formers are subject to significant morbidity that negatively impacts their health-related quality of life (HRQOL). We sought to determine the impact of age at kidney stone onset, duration of stone disease, and kidney stone event (surgery or stone passage) on HRQOL of individual patients by querying the validated and prospectively collected Wisconsin Stone Quality of Life (WISQOL) database. Patients and Methods: Cross-sectional data were obtained from a total of 2438 kidney stone formers from 14 institutions in North America who completed the WISQOL questionnaire during the period from 2014 to 2019. The 28-question survey has a 1- to 5-point scale for each item (total score range 0-140). Multivariable linear regression models assessed the impact of age at kidney stone onset, duration of stone disease, and time since most recent surgery or stone passage on HRQOL. Results: Of 2438 patients, older age at kidney stone onset and longer duration of disease were both independent predictors of better WISQOL scores ( β  = 0.33 points/year; confidence interval [CI] 0.17-0.49; p  < 0.001; and β  = 0.50 points/year; CI 0.32-0.68; p  < 0.001, respectively). Of 1376 patients who underwent surgery between 2010 and 2019, longer time since most recent surgery was an independent predictor of better WISQOL scores ( β  = 2.28 points/year; CI: 1.47-3.10; p  = <0.001). Of 1027 patients with spontaneous stone passage occurring between 2010 and 2019, longer time since most recent stone passage was an independent predictor of better WISQOL scores ( β  = 1.59 points/year; CI: 0.59-2.59; p  = <0.05). Conclusions: Our study demonstrates that older age at onset, longer duration of disease, and longer time since most recent surgery or stone passage were independent predictors of better HRQOL in kidney stone formers. Results of future studies that focus on optimizing stone-related modifiable risk factors to decrease the number of recurrent stone episodes and thus the need for recurrent surgeries will be essential.

Purpose: The coronavirus disease 2019 (COVID-19) pandemic is an unprecedented global event that has caused significant fear and anxiety across all populations. To date, there have been no studies on how major health crises have affected the stone-related quality of life (QOL) of urolithiasis patients. In this multi-institutional study, we investigated the association between fear of COVID-19 and the QOL of urolithiasis patients during the COVID-19 pandemic using the Fear of COVID-19 Scale (FCV-19S) and the Wisconsin Stone Quality of Life (WISQOL) questionnaires. Materials and Methods: Patient-reported data collection occurred between April and October 2020 during the COVID-19 pandemic where many procedures (radiologic or surgical) and visits were either delayed or cancelled. The scores generated from patient-reported responses to questionnaires were correlated and then further subanalyzed dependent on categorical responses related to procedural delays or care and were analyzed via the Student's t -test. A single factor analysis of variance (ANOVA) was performed to analyze varying QOL scores across the FCV-19S quartiles. Results: Four hundred respondents participated in this study. Overall mean total standardized FCV-19S and WISQOL scores (both transformed to min-max 0-100) were 34.3 and 70.3, respectively. A significant inverse correlation ( r  = -0.265, p  < 0.0001) demonstrated that suggesting greater COVID-19 fear may result in lower stone-related QOL. A significant difference in fear and QOL scores was observed between the sexes, with women having more COVID-19 fear (35.8 vs 28.6, p  < 0.01) and lower stone-related QOL (64.2 vs 75.2, p  < 0.01). Quartile ANOVA analysis revealed significant mean difference in WISQOL scores across all FCV-19S score quartiles ( p  < 0.05). Conclusions: Using two validated questionnaires (FCV-19S and WISQOL) and correlating patient-reported responses, we found that greater fear for COVID-19 was associated with lower stone-related QOL in urolithiasis patients.

The objective is to explore the need for future surgery among patients treated for asymptomatic concurrent contralateral stones versus those that were not. Upon IRB approval, we retrospectively reviewed records of patients who underwent stone surgeries (SWL, URS, PCNL) from 2009 to 2018. Patients were included if they were greater than 18 years old, had a minimum follow-up of 2 years, and had pre-operative imaging. Patients were divided into three groups: bilateral surgery, ipsilateral surgery with, and without asymptomatic concurrent contralateral stones. Cox regression was used to analyze patients' need for future surgery while controlling demographic and comorbid characteristics. Of the 1666 patients included, 51.9% were men. They were 59.7 ± 15 years and had a BMI of 31.3 ± 8.2 kg/m 2 . During the follow-up of 5.2 ± 2.2 years (range 2-11 years), patients who had bilateral surgery and patients who had ipsilateral surgery without treatment of the asymptomatic concurrent contralateral stones had no difference in the need for future surgery (41.7% vs. 43%, p = 0.585). When stratified by stone size, patients with contralateral stones > 6 mm were more likely to require future surgical treatment than those treated bilaterally (p < 0.001). Our study demonstrates that treating asymptomatic concurrent contralateral stones does not lower the need for future surgical interventions. However, asymptomatic concurrent contralateral stones > 6 mm may portend earlier need for treatment. Therefore, bilateral treatment should be considered at presentation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: To evaluate the clinical benefits of Moses technology compared with the regular mode with the Lumenis ® Pulse™ P120H holmium laser during ureteroscopy for stone disease. Patients and Methods: An IRB-approved database of patients with urolithiasis was analyzed for ureteroscopies from January 2020 to December 2020 at an outpatient surgery center. Patients who underwent ureteroscopy with the Lumenis Pulse P120H holmium laser system with the Moses or regular mode were included. Patient characteristics and stone parameters were collected. Operative room parameters were compared, including procedural time, fragmentation/dusting time, lasing time, and total energy used. Complication rates and stone-free rates were also analyzed. Univariate analysis and multiple analysis of covariance controlling for cumulative stone size were performed. Patients with staged procedures were excluded. Results: Of 197 surgical cases, 176 met the inclusion criteria. Moses was utilized in 110 cases and regular mode in 66. There was no difference in cumulative stone size between Moses and regular modes (11.8 ± 7.9 vs 11.6 ± 9.2 mm, p  = 0.901). Procedural time (43.5 ± 32.1 vs 39.8 ± 24.6 minutes, p  = 0.436), fragmentation/dusting time (20.5 ± 25.3 vs 17.1 ± 16.1 minutes, p  = 0.430), lasing time (7.5 ± 11.1 vs 6.7 ± 7.9 minutes, p  = 0.570), and total energy used (5.1 ± 6.7 vs 3.8 ± 4.8 kJ, p  = 0.093) were also similar. Complications (6.4% vs 6.1%, p  = 0.936) and stone-free rates (52.3% vs 65.3%, p  = 0.143) did not differ. Conclusion: At our institution, Moses technology did not significantly change the procedural time, fragmentation/dusting time, lasing time, or total energy used. Moreover, there were no differences in complications or stone-free rates. There may be technical benefits to the Moses technology not captured in this analysis.

Our objective was to analyze and compare the associations between potential risk factors for nephrolithiasis and repeat stone surgery in male and female patients. We retrospectively analyzed 1970 patients who had stone surgery at our institution in the period from January 2009 to May 2017, were older than 18 years and had at least 12 months of postoperative follow-up. Our definition of surgical recurrence included repeat surgery on the same renal unit or on the opposite renal unit if the original imaging did not demonstrate significant stones on that side. Uni- and multivariate Cox regression models were built for each gender. We also explored the interactions between gender and other patient's characteristics in their effect on the risk of recurrence. Ureteroscopy was the most common treatment modality for both first (83%) and repeat (87%) procedures. Over a mean follow-up of 4.3 years (median 3.8, interquartile range 2.2-6.0), 413 (21.0%) patients had a surgical recurrence. In multivariate analyses, hypertension, diabetes, Caucasian race and younger age (less than 60 years) were significantly associated with the risk of surgical recurrence only in females. Interaction between these characteristics and gender was significant indicating a larger effect on the risk of surgical recurrence in females compared to males. Our study demonstrated a number of differences in the predictors of repeat surgery for nephrolithiasis between males and females. If confirmed by future studies these differences may be helpful for optimizing nephrolithiasis prevention efforts., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Objectives: To determine the safety and efficacy of flexible ureteroscopy in the treatment of transplant urolithiasis. Materials and Methods: We reviewed a single-center series of 2652 patients who underwent surgical treatment for nephrolithiasis at our institution from 2009 to the present day to identify all patients undergoing ureteroscopy for treatment of transplant lithiasis. Results: We identified 18 patients who underwent ureteroscopy for treatment of urolithiasis within the transplanted kidney or ureter. The majority of the procedures were performed using a retrograde approach with flexible ureteroscopy, with one patient undergoing antegrade ureteroscopy and two patients requiring semirigid ureteroscopy. Holmium:yttrium-aluminum-garnet laser lithotripsy was utilized in all but one case, which was performed using basket extraction. There were no intraoperative complications reported. Four patients had small stone fragments on postoperative imaging, three of which were observed. One patient required repeat ureteroscopy for persistent distal ureteral stone. Conclusion: Retrograde ureteroscopy is a feasible, safe, and effective intervention for the treatment of transplant lithiasis. Minimal intraoperative or postoperative complications were reported, and only one patient required additional intervention for residual stone burden.

Background: Drug-induced urolithiasis falls into two categories: drug-induced and metabolically-induced. Certain antimicrobials are associated with each; sulfonamides are associated with drug- or metabolite-containing calculi when taken in large doses over a long period of time. Trimethoprim-sulfamethoxazole, a member of the sulfonamide family, is a rare cause of drug-induced calculi. Cases of sulfonamide urolithiasis occurring in patients with known stone disease have rarely been reported., Case Presentation: We report a case of a patient with a brief history of recurrent calcium oxalate nephrolithiasis requiring 2 ureteroscopic procedures whose existing 6 mm lower pole renal stone more than quadrupled in size to form a 4 cm renal staghorn after 4 months of high-dose treatment for Nocardia pneumonia with trimethoprim-sulfamethoxazole. After ureteroscopy with laser lithotripsy and basketing of fragments, the stone was found to be predominantly composed of N 4 -acetyl-sulfamethoxazole, a metabolite of sulfamethoxazole., Conclusion: Stones composed of sulfamethoxazole or its metabolites are rare but have known associated risk factors that should be considered when prescribing this antibiotic. This case report illustrates additional risk factors for consideration, including pre-existing urinary calculi that may serve as a nidus for sulfamethoxazole deposition, and reviews treatment and prevention methods., (© 2021. The Author(s).)

Management options for small renal masses include active surveillance, partial nephrectomy, radical nephrectomy, and thermal ablation. For tumors typically ≤3 cm in size, thermal ablation is a good option for those desiring an alternative to surgery or active surveillance, especially in patients who are considered high surgical risk. We favor microwave ablation because of the more rapid heating, higher temperatures that overcome the heat sink effect of vessels, reproducible cell kill, and a highly visible ablation zone formed by water vapor that corresponds well to the zone of necrosis. For central tumors, we favor cryoablation because of the slower formation of the ablation zone and less likelihood of damage to the collecting system. With microwaves, it is important to monitor the ablation zone in real time (ultrasound is the best modality for this purpose), avoid direct punctures of the collecting system, and to place probes tangential to the collecting system to avoid burning open a persistent tract between the urothelium and extrarenal spaces or causing strictures. The surgical steps described in this video cover our use of high-frequency jet ventilation with general anesthesia to minimize organ motion, initial imaging and targeting, probe insertion, hydrodissection (a technique that enables displacement of adjacent structures), the ablation itself, and finally our dressing. Postoperative cares typically consist of observation with a same-day discharge or an overnight stay. Follow-up includes a magnetic resonance imaging abdomen with and without contrast, chest X-ray, and laboratories (basic metabolic panel, complete blood count, and C-reactive protein) 6 months postablation. Overall, percutaneous microwave ablation is an effective and safe treatment option for renal cell carcinoma in both T1a and T1b tumors in selected patients with multiple studies showing excellent oncologic outcomes when compared with partial and radical nephrectomy.

To evaluate the impact of chronic stone recurrence on an individual's quality of life using the validated Wisconsin Stone Quality of Life (WISQOL) questionnaire. We collected cross-sectional data on patients with kidney stones from 14 institutions in North America. A stone event was defined as renal colic, stone-related procedure or emergency department visit. The regression analyses using general linear models and pairwise comparison determined the impact of the number of stone events on quality of life. The median number of stone events among the 2205 patients who completed the questionnaire was 3 (IQR 1-6). The mean total score was 107.4 ± 28.7 (max 140 points). The number of lifetime stone events was an independent predictor of lower quality of life (p < 0.001), specifically, score declined significantly beyond five events. Compared with patients who experienced a single stone event, there was a 0.4, 2.5, and 6.9 point decline in the adjusted mean WISQOL score after 2-5, 6-10, or > 10 events, respectively. The cumulative number of lifetime stone events was associated with a lower quality of life when more than five stone events were occurred. These findings underscore the importance of efforts to determine the underlying metabolic etiology of urolithiasis in the recurrent stone former, and the institution of a regimen to place their stone disease in remission., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

INTRODUCTION The objective of this study is to explore the association between urinary stone composition and surgical recurrence., Materials and Methods: Patients who underwent kidney stone surgeries (between 2009-2017), were followed for > 1 year, and had ≥ 1 stone composition analyses were included in our analysis. Surgical stone recurrence (repeat surgery) was defined as the second surgery on the same kidney unit. Recurrence-free survival analysis was used., Results: A total number of 1051 patients were included (52.7% men, average age 59.1 +/- 15.1 years). Over 4.7 +/- 2.5 years follow up, 26.7% of patients required repeat surgery. Patients' stone compositions were calcium oxalate (66.0%), uric acid (12.2%), struvite (10.0%), brushite (5.7%), apatite (5.1%) and cystine (1.0%). Results suggested that patients with cystine stones had the highest surgical recurrence risk; brushite had the second-highest surgical recurrence risk. Struvite, uric acid, and apatite stones were at higher risk compared with calcium oxalate stones (lowest risk in our cohort). When pre and postoperative stone size was controlled, patients with a history of uric acid, brushite, and cystine stones were at higher surgical risk. After controlling clinical and demographic factors, only brushite and cystine stones were associated with higher surgical recurrence., Conclusions: Patients with cystine stones had the highest surgical recurrence risk; brushite stones had the second highest surgical recurrence risk. Struvite, uric acid, and apatite stones were at higher risk compared with calcium oxalate stones. When pre and postoperative stone size, clinical and demographic factors were controlled, only those with brushite or cystine stones were at significantly higher risk of surgical recurrence.

Objective: To build the Wisconsin Stone Quality of Life Machine-Learning Algorithm (WISQOL-MLA) to predict urolithiasis patients' health-related quality of life (HRQoL) based on demographic, symptomatic and clinical data collected for the validation of the Wisconsin Stone Quality-of-Life (WISQOL) questionnaire, an HRQoL measurement tool designed specifically for patients with kidney stones., Material and Methods: We used data from 3206 stone patients from 16 centres. We used gradient-boosting and deep-learning models to predict HRQoL scores. We also stratified HRQoL scores by quintile. The dataset was split using a standard 70%/10%/20% training/validation/testing ratio. Regression performance was evaluated using Pearson's correlation. Classification was evaluated with an area under the receiver-operating characteristic curve (AUROC)., Results: Gradient boosting obtained a test correlation of 0.62. Deep learning obtained a correlation of 0.59. Multivariate regression achieved a correlation of 0.44. Quintile stratification of all patients in the WISQOL dataset obtained an average test AUROC of 0.70 for the five classes. The model performed best in identifying the lowest (0.79) and highest quintiles (0.83) of HRQoL. Feature importance analysis showed that the model weighs in clinically relevant factors to estimate HRQoL, such as symptomatic status, body mass index and age., Conclusions: Harnessing the power of the WISQOL questionnaire, our initial results indicate that the WISQOL-MLA can adequately predict a stone patient's HRQoL from readily available clinical information. The algorithm adequately relies on relevant clinical factors to make its HRQoL predictions. Future improvements to the model are needed for direct clinical applications., (© 2020 The Authors BJU International © 2020 BJU International.)

Objective: To compare the health-related quality of life (HRQOL) of patients with residual fragments after surgical intervention for kidney stones to patients that are stone-free using the disease-specific Wisconsin stone quality of life (WISQOL) questionnaire. Kidney stones contribute to impaired HRQOL, which is increasingly recognized as an important healthcare outcome measurement., Materials and Methods: With institutional review board approval, 313 adult patients who underwent surgical intervention for kidney stones at 4 sites completed a WISQOL questionnaire. We retrospectively collected surgical data including presence of residual fragments on post-operative imaging. We calculated standardized WISQOL total and domain scores (0-100), which included items related to social functioning (D1), emotional functioning (D2), stone-related impact (D3), and vitality (D4). Scores were compared between patients with residual fragments to those who were stone-free after surgical intervention., Results: Demographics did not differ between groups, overall mean age 54.6 ± 13.5 and 55.4% female. There was no significant difference in total WISQOL score for patients with residual fragments (n = 124) compared to patients that were stone-free (n = 189), 110.5 ± 27.8 vs 115.4 ± 23.6 respectively, (P = .12). Interestingly, patients with residual fragments who underwent secondary surgery were found to have significantly lower total WISQOL score (88.4 ± 30.1 vs 116.6 ± 25.0, P <.0001)., Conclusion: Stone-free status after surgical intervention is not associated with better HRQOL when compared with patients whose surgeries left residual fragments. Indeed, further surgical intervention on residual fragments to achieve stone-free status may actually result in worse HRQOL., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Objective: To determine if socioeconomic status (SES) correlates with severity of kidney stone disease and 24-hour urine parameters., Materials and Methods: An IRB approved prospectively maintained database for nephrolithiasis was retrospectively analyzed for both 24-hour urine results and surgical procedures performed from 2009 to 2019. Severely distressed communities (SDC) were categorized as those with a Distressed Communities Index (DCI), a composite measure of SES, score in the top quartile (lowest for SES). Univariate and multivariate analyses were performed to evaluate the strength of the association of DCI on: stone size at presentation, need for and type of surgical procedure, need for staged surgery and specific stone risk factors in 24-hour urine collections., Results: Surgical procedures were performed on 3939 patients (1978 women) who were not from SDC and 200 (97 women) from SDC. Patients from SDC were older (57.1 years vs 54.2 years; P = .009). Patients from SDC were more likely to undergo proportionally more invasive procedures (17.5% vs 11.6%; P = .011) and require staged surgery at a higher rate (13.0% vs 8.5%; P = .028). Men from SDC had larger stones (12.5 mm vs 9.7 mm; P = .001). Among 24-hour urine results from 2454 patients (1187 women), DCI was not correlated with sodium, calcium, magnesium, volume, oxalate, phosphate, and pH levels. Higher DCI (lower SES) correlated with lower urine citrate (P = .001) and lower urine potassium (P = .002)., Conclusion: SES correlates with larger stone burden at the time of urologic intervention, requires proportionally more invasive procedures and more staged procedures. Lower SES correlated with lower urine citrate and potassium., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: Metabolic syndrome (MetS) is a cluster of metabolic diseases that is linked to atherosclerotic cardiovascular disease. MetS has also been linked to increased nephrolithiasis. However, limited research has been conducted on MetS and its impact on stone-specific health-related quality of life (HRQOL). This study aims to examine the hypothesis that the presence of MetS is associated with decreased HRQOL. Materials and Methods: The Wisconsin Stone Quality of Life Questionnaire, a stone-specific HRQOL questionnaire, was used to survey 3051 patients with kidney stones. Medical history was collected from patients. These data were used to distinguish MetS patients from non-MetS patients. Among patients with current stones, a Wilcoxon rank sum test was used to compare HRQOL scores from MetS patients and non-MetS patients. HRQOL from patients with and without individual MetS components were also compared, and a multivariate analysis was conducted. Results: Statistical comparison between MetS patients (median score 102/140) and non-MetS patients (median score 106/140) demonstrated a lower stone-specific HRQOL in patients with MetS ( p  = 0.049). Among individual MetS components, patients with diabetes mellitus (DM) or body mass index (BMI) >30 had significantly lower HRQOL than patients without DM or BMI <30 ( p  = 0.028 and p  < 0.001, respectively). The multivariate analysis supported this trend as MetS remained a significant predictor of decreased HRQOL ( p  = 0.002) after controlling for other variables assessed. Conclusions: This study indicates an association between MetS and a lower stone-specific QOL. This has important implications for stone prevention strategies in patients with MetS. Clinical Trial Registration number: H14-01143.

Introduction: Despite proven effectiveness of medications in preventing stone recurrence, compliance with pharmacotherapy (PT) is often poor because of cost, side effects, and impact on lifestyle. We sought to compare the risk of stone recurrence between patients managed with conservative therapy (CT) vs PT controlling for aggressiveness of stone disease. Materials and Methods: The Multi-center collaboration to Study Treatment Outcomes in Nephrolithiasis Evaluation (MSTONE) database contains patient data and outcomes from July 2001 to April 2015 across four centers. The database was queried for patients whose stone disease was managed with CT alone (fluid and dietary recommendations) vs PT. Patients were risk stratified according to number of previous passed stones. Within each risk group, we compared CT vs PT with respect to 2-year stone event rate and stone event-free survival (SEFS) using the Kaplan-Meier method. Results: A total of 245 patients, with a median follow-up of 29 months (interquartile range = 16-44), were identified, including 93 on CT and 152 on PT. The overall 2-year stone event rate was 38% for all patients. Stone events at 2 years occurred less frequently in the PT group compared with the CT group (31% vs 44%, p  = 0.043), with the difference most pronounced in the high-risk group (71% vs 32% for CT and PT, respectively, p  = 0.058). The 30-month SEFS was significantly higher for PT (58%) than CT (46%) overall. When stratified by risk group, 30-month SEFS was statistically significantly higher for PT than CT in the intermediate risk group (65% vs 45% for PT and CT, respectively). Conclusion: Controlling for aggressiveness of stone disease, PT was more effective than CT in reducing and delaying stone-related events. However, CT appeared to be as effective as PT in low-risk patients. PT is best reserved for recurrent stone formers, regardless of metabolic background.

Management of residual or recurrent disease following thermal ablation of renal cortical tumors includes surveillance, repeat ablation, or surgical extirpation. We present a multicenter experience with regard to the management of this clinical scenario. Prospectively maintained databases were reviewed to identify 1265 patients who underwent cryoablation (CA) or radiofrequency ablation (RFA) for enhancing renal masses. Disease persistence or recurrence was classified into one of the three categories: (i) residual disease in ablation zone; (ii) recurrence in the ipsilateral renal unit; and (iii) metastatic/extra-renal disease. Seventy seven patients (6.1%) had radiographic evidence of disease persistence or recurrence at a median interval of 13.7 months (range, 1-65 months) post-ablation. Distribution of disease included 47 patients with residual disease in ablation zone, 29 with ipsilateral renal unit recurrences (all in ablation zone), and one with metastatic disease. Fourteen patients (18%) elected for surveillance, and the remaining underwent salvage ablation (n = 50), partial nephrectomy (n = 5), or radical nephrectomy (n = 8). Salvage ablation was successful in 38/50 (76%) patients, with 12 failures managed by observation (3), tertiary ablation (6), and radical nephrectomy (3). At a median follow-up of 28 months, the actuarial cancer-specific survival and overall survival in this select cohort of patients was 94.8 and 89.6%, respectively., Competing Interests: The authors declare no potential conflicts of interest with respect to research, authorship, and/or publication of this article., (Copyright: Loloi J et al.)

Introduction: The development of renal stones in space would not only impact the health of an astronaut but could critically affect the success of the mission., Materials and Methods: We reviewed the medical literature, texts and multimedia sources regarding the careers of Dr. Abraham Cockett and Dr. Peggy Whitson and their contributions to the study of urolithiasis in space, as well as the studies in between both of their careers that helped to further characterize the risks of stone formation in space., Results: Dr. Abraham T. K. Cockett (1928-2011) was Professor and Chair of the Department of Urology at the University of Rochester and served as AUA President (1994-1995). In 1962, Dr. Cockett was one of the first to raise a concern regarding astronauts potentially forming renal stones in space and suggested multiple prophylactic measures to prevent stone formation. Many of the early studies in this field used immobilized patients as a surrogate to a micro-gravity environment to mimic the bone demineralization that could occur in space in order to measure changes in urinary parameters. Dr. Peggy A. Whitson (1960-), is a biochemistry researcher and former NASA astronaut. She carried out multiple studies examining renal stone risk during short term space shuttle flights and later during long-duration Shuttle-Mir missions., Conclusion: From the early vision of Dr. Cockett to the astronaut studies of Dr. Whitson, we have a better understanding of the risks of urolithiasis in space, resulting in preventive measures for urolithiasis in future long duration space exploration.

Objectives: Influence of renal anatomy on success rates for shockwave lithotripsy has been reported in the literature with emphasis on lower pole anatomy. Influence of renal anatomy has not been evaluated in the setting of ureteroscopy and laser lithotripsy for stone treatment. This study analyzed the influence of infundibulopelvic angle (IPA) of the lower pole on the outcomes of ureteroscopy and laser lithotripsy with respect to stone-free rate and surgical recurrence. Materials and Methods: We retrospectively analyzed 735 renal units undergoing retrograde flexible ureteroscopy (fURS) with laser lithotripsy between January 2009 and December 2016. All cases were performed at a single institution. No exclusion criterion was applied with regard to preoperative stone location. Success was defined as no evidence of residual stone fragments on kidney, ureter, and bladder radiograph within 2 months of surgery. Failure was defined as any stone present on imaging. Lower pole IPA was measured on intraoperative retrograde pyelogram as described by Elbahanasy et al. Univariate and multivariate analyses of factors contributing to stone-free rate were performed. Secondary outcomes included surgical recurrence-free survival. Results: Of the 735 cases evaluated, 243 cases had a retrograde pyelogram stored in our Picture Archiving and Communication System (PACS) sufficient for IPA interpretation. Of these patients, 122 (50%) were women. In total, 127 patients (52.3%) were stone free on follow-up imaging, whereas 116 (47.7%) had residual stone burden. In total, 144 (59%) patients had ≤3 mm stone burden on follow-up imaging. In multivariate analysis, residual stone fragments were significantly associated with acute IPA <90° (<0.001), lower pole stones preoperatively (<0.001), and larger stone size (0.001). IPA <90° and larger stone size were both found to be statistically significantly associated with need for repeat surgery. Conclusions: Our data show that more acute IPA and larger preoperative stone size negatively affect stone-free rate and need for repeat surgery after retrograde fURS with laser lithotripsy for treatment of renal stones.

Introduction: Urolithiasis causes a significant impact on health-related quality of life (HRQOL). Patients with kidney stones have high levels of stress and anxiety. Symptom resolution often requires treatment. Travel distance is a barrier to care but little is known about its effects on HRQOL. We hypothesize that increased distance to treatment site is associated with decreased HRQOL., Methods: Patients with a history of stones were enrolled at 11 tertiary centers as part of the QOL Stone Consortium of North America. HRQOL data were obtained using the Wisconsin Stone Quality of Life questionnaire (WISQOL). We calculated distance between patient and treatment site using national ZIP codes. We used linear models to evaluate the effect of distance on HRQOL, while also considering demographics data, stones/symptom status, and distance., Results: Of the 1676 enrolled patients, 52% were male, 86% non-Latino White, and the mean age was 53 years. Mean distance to treatment site was 63.3 km (range 0-3774), with 74% reporting current stones and 45% current symptoms. WISQOL score and distance were negatively correlated for patients reporting current stones and symptoms (p=0.0010). Linear modelling revealed decreased WISQOL scores for patients with symptoms as distance increased from treatment site (p=0.0001), with a 4.7-point decrease for every 100 km traveled., Conclusions: Stone disease imposes significant burden on patients' HRQOL due to a variety of factors. Patients with active stone symptoms report worse HRQOL with increased distance to their treatment site. Possible etiologies include travel burden, increased disease burden, decreased healthcare use, and delays in care.

Objective: To compare perioperative and oncologic outcomes for patients with clinical T1b renal cell carcinoma following treatment with microwave ablation (MW), partial nephrectomy (PN), or radical nephrectomy (RN)., Methods: Comprehensive clinical and pathologic data were collected for nonmetastatic renal cell carcinoma patients with cT1b tumors following MW, PN, or RN from 2000 to 2018. Local recurrence-free, metastasis-free, cancer-specific and overall survival were estimated using Kaplan-Meier method. Prognostic factors for complications and survival were determined using logistic regression and Cox hazard models, respectively., Results: A total of 325 patients (40 MW, 74 PN, and 211 RN) were identified. Patients treated with MW were older with higher Charlson comorbidity indices compared to surgical patients. Median length of hospitalization was shorter for MW compared to surgical patients (1 day vs 4 days, P <.0001). Post-treatment estimated glomerular filtration rate decreased by median 4.5% for MW compared to 3.2% for PN (P = .58) and 29% for RN (P <.001). Median follow-up was 34, 35, and 49 months following MW, PN, and RN, respectively. Estimated 5-year local recurrence-free survival was 94.5% for MW vs 97.9% for PN (P = .34) and 99.2% for RN (P = .02). Two patients recurred after MW and underwent repeat ablation without subsequent recurrence. No difference in 5-year metastasis-free survival or cancer-specific survival was found among MW, PN, or RN. Four (10%) MW patients had high-grade complication. Only prior abdominal surgery predicted high-grade complication (OR 6.29, P = .017)., Conclusion: Microwave ablation is a feasible alternative to surgery in select comorbid patients with clinical T1b renal cell carcinoma., (Copyright © 2019. Published by Elsevier Inc.)

Objective: To analyze risk factors and patterns of RCC recurrence following percutaneous ablation for stage 1 tumors and develop risk-stratified follow-up imaging protocols., Method: Biopsy-proven sporadic stage 1 RCC patients treated with percutaneous microwave ablation (MWA) or cryoablation (CA) from 2002 to 2017 were included. Kaplan-Meier analysis was used to estimate local and distant recurrence-free survival, cancer-specific survival and metastatic-free survival. Multivariable models were used to identify risk factors associated with recurrence., Results: A total of 256 patients with stage 1 RCC (215 T1a, 41 T1b) were treated with percutaneous MWA (178 subjects) or CA (78 subjects). Recurrence was identified in 23 patients (16 local, 7 distant). Clinical T stage (HR 2.46, 95% CI 1.06-5.72, P = .04) and tumor grade (HR 4.17, 95% CI 1.17-14.76, P = .03) were independent predictors of recurrence. Recurrence was not associated with Nephrometry score, cystic tumors, ablation modality (CA vs MWA) or gender. Five-year cancer-specific survival, and metastatic-free survival were 98.6% and 97.4%, respectively. Patients were stratified into 2 groups: reduced risk stage 1 (no risk factors) or elevated risk stage 1 (≥1 risk factor). Recurrence risk was higher in the elevated-risk group (HR = 3.19, 95% CI 1.35-7.53, P = .008). Five-year overall recurrence-free survival (local + distant) was higher in reduced-risk vs elevated-risk cohorts, 88% vs 69%, P = .005., Conclusion: High nuclear grade or T1b tumors have increased recurrence risk following percutaneous thermal ablation for stage 1 RCC. Current postablation follow-up protocols may be modified for individual recurrence risk to allow more frequent imaging for elevated-risk patients, while enabling less frequent imaging for reduced-risk patients., (Copyright © 2019. Published by Elsevier Inc.)

Objective: To identify the clinical and demographic predictors of repeat stone surgery., Materials and Methods: We retrospectively analysed 1496 consecutive patients, aged > 18 years, who underwent stone surgery at our institution in the period from January 2009 to May 2017 and who had at least 12 months of postoperative follow-up. We defined surgical recurrence as repeat surgery on the same renal unit or on the opposite renal unit if the original imaging did not demonstrate significant stones on that side. Characteristics associated with the risk of surgical recurrence in univariate Cox regression analysis were entered into a multivariate model., Results: Most patients underwent ureteroscopy and laser lithotripsy (83.0%). Approximately 60% of the patients had a personal history of stone disease and 50% were obese. Over a mean (median; interquartile range) follow-up of 4.1  (3.9; 2.4-5.9) years, 24.5% of patients had surgical recurrence, with 82% of repeat surgeries performed for symptomatic nephrolithiasis. The factors associated with increased risk of surgical recurrence in the multivariate model were: age <60 years, female gender, malabsorptive gastrointestinal disease, diabetes, recurrent urinary tract infections, personal history of nephrolithiasis, renal stones and bilateral nephrolithiasis. The hazard ratios for these variables ranged within an interval of <0.5 (from 1.30 to 1.71)., Conclusion: We identified eight demographic and clinical factors associated with increased risk of repeat renal stone surgery. These factors could be combined as a numerical count that allows stratification of patients into low-, intermediate- and high-risk subgroups., (© 2019 The Authors BJU International © 2019 BJU International Published by John Wiley & Sons Ltd.)

Objective: We present our experience of the treatment of reservoir stones using a percutaneous approach in patients with Indiana pouch urinary diversions., Material and Methods: Patients who were treated percutaneously for Indiana pouch reservoir stones between January 2008 and December 2018 were identified from the hospital database, and their data were retrospectively analyzed. Patient charts were reviewed for stone burden, surgery details, and postoperative complications. The Indiana pouch was punctured under a direct ultrasound guidance, and a 30F sheath was placed into the pouch. A urologist removed the stones by inserting a rigid nephroscope through the sheath. A Foley catheter was left in the pouch through the percutaneous tract and opened to drainage., Results: Seven patients (mean age: 47.3±14.7 years) were included. All patients were stone free after the procedure. The median stone number was 3 (range: 1-8). The mean maximum stone diameter was 24.4±4.9 mm (range: 19-33 mm). Six patients were successfully treated in one session, whereas 1 patient required two treatment sessions. The median postoperative hospital admission was 1 day (range: 1-5 days). The Foley catheters were removed after a median of 18 days (range: 10-19 days). No major complications were reported., Conclusion: The percutaneous approach for Indiana pouch reservoir stones treatment ensures direct and safe management without major periprocedural complications.

Purpose: Kidney stone formers have lower health related quality of life than nonstone formers. The North American Stone Quality of Life Consortium is a multicenter, longitudinal, prospective study of health related quality of life in patients with kidney stones using the WISQOL (Wisconsin Stone Quality of Life Questionnaire) with data on 2,052 patients from a total of 11 centers. This study is a subanalysis of cross-sectional data looking at the association of age, gender and race on health related quality of life of stone formers., Materials and Methods: We performed multivariable analyses of ordinal logistic regression analyses to determine the impact of age, gender and race on health related quality of life, adjusting for other baseline covariates. The proportional odds assumption of ordinal logistic regression was checked. Total score and scores on 4 subdomains (social functioning, emotional functioning, stone related impact and vitality) were included., Results: Median total score for all patients was 80.4. On multivariable analysis older patients had a significantly higher total health related quality of life score than younger patients (per 10-year increase OR 1.25, p <0.0001). Male patients had higher scores than females (OR 1.56, p = 0.0003) and nonCaucasian patients had lower health related quality of life than nonLatino Caucasian patients (OR 0.63, p = 0.0045)., Conclusions: Younger and female patients with kidney stones have lower health related quality of life than older and male patients, respectively. NonCaucasian patients with stones also have lower health related quality of life. The clinical impact of these findings might include future implications for patient counseling, including dietary and medical management of stone disease, and potential changes to the paradigm of the surgical management of stones.

Purpose: Kidney stones are a source of significant morbidity which have been shown to negatively impact health related quality of life. We sought to understand the association between health related quality of life, socioeconomic status and race among patients with kidney stones., Materials and Methods: Patients with stones at a total of 11 stone centers across the United States completed the WISQOL (Wisconsin Stone Quality of Life questionnaire). The patient ZIP Code™ was used to estimate household income. A mixed effects regression model was constructed for analysis with ZIP Code as the random intercept., Results: A total of 2,057 stone formers completed the WISQOL. Lower income was independently associated with significantly lower health related quality of life (β = 0.372, p = 0.014), as were nonwhite race (β = -0.299, p = 0.001), unemployed work status (β = -0.291, p = 0.008), female gender (β = -0.204, p <0.001), body mass index greater than 40 kg/m 2 (β = -0.380, p <0.001), 5 or more medical comorbidities (β = -0.354, p = 0.001), severe recurrent stone formation (β = -0.146, p = 0.045), enrollment at an acute care visit, or a preoperative or postoperative appointment (β = -0.548, p <0.001) and recent stone symptoms (β = -0.892, p <0.001)., Conclusions: Lower income, nonwhite race and unemployed work status were independently associated with lower health related quality of life among patients with kidney stones. While clinical characteristics such as body mass and stone disease severity were also associated with health related quality of life, this study shows that socioeconomic factors are similarly important. Further research to understand the specific mechanisms by which socioeconomic status and race impact health may lend insight into methods to optimize clinical treatment of stone formers and patients with other chronic diseases.

Objective: To assess the performance of recurrence of kidney stone (ROKS) nomogram in identifying first-time stone formers who will require future stone procedures. Materials and Methods: From January 2009 to February 2016, 2287 patients underwent surgical treatment for nephrolithiasis at our institution and 498 of them were eligible for this study. We defined recurrence as repeat surgery for symptomatic nephrolithiasis. We analyzed the performance of the nomogram with respect to discrimination, calibration, and the clinical net benefit. We also examined the performance of each individual variable from the nomogram. Results: Over a median follow-up of 4.8 years (mean 4.6, IQR 3.1-6.1), 88 patients (17.7%) had recurrent nephrolithiasis requiring surgical treatment. The ROKS nomogram demonstrated moderate discriminative ability (AUC 0.655 for 2 years and 0.605 for 5 years). Calibration of the ROKS nomogram-based predictions was poor and net clinical benefit was minimal. Three of 11 predictors from the nomogram were statistically significantly associated with the risk of repeat surgery, with two of them representing similar clinical scenarios, namely symptomatic and nonsymptomatic renal stones. Conclusion: ROKS nomogram demonstrated limited discrimination and calibration in predicting the risk of repeat surgery for symptomatic nephrolithiasis in our cohort of first-time stone formers. This may be caused by the differences between stone patients who do and do not require surgery and suggests the need for development of more precise prediction instruments.

Purpose: The purpose of this study was to evaluate patient, tumor and technical factors associated with procedural complications and nondiagnostic findings following percutaneous core renal mass biopsy., Materials and Methods: We reviewed core renal mass biopsies from 2000 to 2017. Complications at 30 days or less were graded using the Clavien-Dindo system. Univariate and multivariable analyses were done to evaluate associations between clinical characteristics and the risk of complications or nondiagnostic findings., Results: Of the 1,155 biopsies performed in a total of 965 patients procedural complications were identified in 24 patients (2.2%), including 5 (0.4%) with major complications (Clavien 3a or greater). No patients were identified with tumor seeding of the biopsy tract. Patient age, body mass index, gender, Charlson comorbidity index, smoking, mass diameter, nephrometry score, number of cores and prior biopsy were not associated with complication risk (p = 0.06 to 0.53). Complications were not increased for patients on aspirin or those with low platelets (25,000 to 160,000/μl blood) or a mildly elevated INR (international normalized ratio) (1.2 to 2.0, p = 0.16, 0.07 and 0.50, respectively). The complication risk was not increased during the initial 50 cases of a radiologist or when a trainee was present (p = 0.35 and 0.12, respectively). Nondiagnostic findings were present in 14.6% of biopsies. Independent predictors included cystic features, contrast enhancement, mass diameter and skin-to-mass distance (p <0.001, 0.002, 0.02 and 0.049, respectively). Radiologist experience was not associated with the nondiagnostic rate (p = 0.23). Prior nondiagnostic biopsy was not associated with an increased nondiagnostic rate on subsequent attempts (19.2% vs 14.2%, p = 0.23)., Conclusions: Procedural complications following biopsy are rare even with low serum platelets, a mildly elevated INR or when the patient remains on aspirin. Cystic features, hypo-enhancement on imaging, a smaller mass diameter and a longer skin-to-tumor distance increase the risk of nondiagnostic findings.

Purpose: We analyzed the impact of residual stone fragments seen on abdominal x-ray after ureteroscopy and laser lithotripsy on the risk of repeat surgical intervention., Materials and Methods: Our study included 781 patients (802 renal units) who underwent ureteroscopy and laser lithotripsy with abdominal x-ray within 3 months postoperatively and who had at least 1 year of followup. Ureteroscopy and laser lithotripsy were performed using the dusting technique. We analyzed the association between surgical recurrence-free survival and the size of the largest residual fragment., Results: During a median followup of 4.2 years repeat surgery was performed on 161 renal units (20%). Of the repeat interventions 75% were done for symptomatic nephrolithiasis. Postoperative imaging showed residual stone fragments in 42% of cases. In the entire group the risk of repeat surgery was increased in renal units with residual fragments greater than 2 mm. The effect of the size of residual fragments on the risk of surgical recurrence varied by patient body mass index. It was much larger in nonobese subjects, who were at increased risk for repeat surgery with residual fragments of any size. In the obese subgroup only fragments greater than 2 mm increased the risk of surgical recurrence., Conclusions: The association between the size of residual stone fragments detected by abdominal x-ray after ureteroscopy and laser lithotripsy, and the risk of repeat surgical intervention depends on patient body mass index. Nonobese patients with residual stone fragments of any size are at increased risk for repeat intervention compared to those with a negative abdominal x-ray. The predictive value of abdominal x-ray after ureteroscopy and laser lithotripsy is limited in obese patients.

Purpose: To describe and validate a novel CT approach using volumetric analysis for renal stone surveillance., Materials and Methods: This prospective trial consisted of a standard low-dose non-contrast CT (SLD) of the abdomen and pelvis, immediately followed by an ultra-low-dose non-contrast CT (ULD) with reconstruction limited to the kidneys. A novel dedicated software tool was applied that automates stone volume, density, and maximum linear size. Manual linear stone size was measured by a radiology fellow and urology resident for comparison. CT dose and clinical charges were considered., Results: Twenty-eight stones in 16 patients were analyzed. Mean effective dose of ULD CT was 0.57 mSv, an average 92% lower than the SLD CT dose. For SLD, mean size ± SD (range) (mm) was 7.9 ± 6.2 (2.6-30.5) for Reader 1, 7.3 ± 6 (2.4-30.7) for Reader 2, and 9.3 ± 6.4 (3.7-33.1) for the automated software. For ULD, mean size ± SD (range) (mm) was 7.3 ± 6 (2.5-30.5) for Reader 1, 7.2 ± 6.1 (2.1-30.7) for Reader 2, and 9.1 ± 6.4 (4.2-32.8) for the automated software. Automated stone diameters were larger than manual diameters for 27/28 stones (mean difference, 23%); difference was ≥ 2 mm in 30%. Average variability between manual measurements was 8.6% (SLD) and 7.8% (ULD), but was 0% for the automated technique. Our institutional charge for ULD renal CT is slightly less than renal US, and > 4× less than SLD CT. The Medicare global fee for the ULD renal CT is less than the SLD CT of the abdomen and pelvis., Conclusions: This focused stone surveillance CT protocol is lower cost and lower dose compared to the standard CT approach. Automated assessment of stone burden provides improved reproducibility over manual linear measurement and offers the advantages of 3D measurements and volumetry. We now offer and perform this protocol in routine clinical practice for stone surveillance.

Purpose: To our knowledge it is unknown whether the benefits of medical management of urolithiasis outweigh the potential side effects of the medications used, including potassium citrate and thiazide diuretics. Therefore, we evaluated the relationship between potassium citrate or thiazides and overall stone related health related quality of life., Materials and Methods: Cross-sectional data were obtained on stone forming enrollees in the North American Stone Quality of Life Consortium. We used the WISQOL (Wisconsin Stone Quality of Life) questionnaire to compare health related quality of life between patients treated and not treated with potassium citrate or thiazide type diuretics. Additionally, the likelihood of gastrointestinal complaints was compared between those prescribed and not prescribed potassium citrate. The likelihood of fatigue and sexual complaints was also compared in those prescribed and not prescribed thiazides., Results: Of the 1,511 subjects, including 787 males and 724 females, 279 were on potassium citrate and 238 were on thiazides at study enrollment. Patients prescribed potassium citrate had higher health related quality of life in each domain vs those not prescribed potassium citrate (p <0.001). Patients prescribed thiazides had higher health related quality of life in each domain compared to those not prescribed thiazide (all p <0.01). Those prescribed potassium citrate were less likely than those not prescribed potassium citrate to report nausea, stomach upset or cramps (OR 0.57, p <0.001). Patients prescribed thiazides were less likely than those not prescribed thiazides to report fatigue (OR 0.63, p = 0.004) or reduced sexual interest and/or activity (OR 0.64, p = 0.005)., Conclusions: Among stone formers the use of potassium citrate and thiazides was associated with better health related quality of life across all WISQOL domains without an increased likelihood of gastrointestinal complaints and fatigue or sexual complaints, respectively. These findings may be useful when counseling patients regarding the initiation of potassium citrate or thiazides for medical management of nephrolithiasis., (Copyright © 2018 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)