Trends and patterns of initial percutaneous nephrolithotomy and subsequent procedures among commercially-insured US adults with urinary system stone disease: a 10-year population-based study.

PURPOSE: To describe trends and patterns of initial percutaneous nephrolithotomy (PCNL) and subsequent procedures from 2010 to 2019 among commercially-insured US adults with urinary system stone disease (USSD). METHODS: Retrospective study of administrative data from the IBM® MarketScan® Database. Eligible patients were aged 18-64 years and underwent PCNL between 1/1/2010 and 12/31/2019. Measures of interest for analysis of trends and patterns included the setting of initial PCNL (inpatient vs. outpatient), percutaneous access (1 vs. 2-step), and the incidence, time course, and type of subsequent procedures (extracorporeal shockwave lithotripsy [SWL], ureteroscopy [URS], and/or PCNL) performed up-to 3 years after initial PCNL. RESULTS: A total of 8,348 patients met the study eligibility criteria. During the study period, there was a substantial shift in the setting of initial PCNL, from 59.9% being inpatient in 2010 to 85.3% being outpatient by 2019 (P < 0.001). The proportion of 1 vs. 2-step initial PCNL fluctuated over time, with a low of 15.1% in 2016 and a high of 22.0% in 2019 but showed no consistent yearly trend (P = 0.137). The Kaplan-Meier estimated probability of subsequent procedures following initial PCNL was 20% at 30 days, 28% at 90 days, and 50% at 3 years, with slight fluctuations by initial PCNL year. From 2010 to 2019, the proportion of subsequent procedures accounted for by URS increased substantially (from 30.8 to 51.8%), whereas SWL decreased substantially (from 39.5 to 14.7%) (P < 0.001). CONCLUSIONS: From 2010 to 2019, PCNL procedures largely shifted to the outpatient setting. Subsequent procedures after initial PCNL were common, with most occurring within 90 days. URS has become the most commonly-used subsequent procedure type.

Development and Validation of a Risk-Adapted Scoring Model for Metachronous Upper Tract Urothelial Carcinoma following Radical Cystectomy.

PURPOSE: The incidence and risk factors for metachronous upper tract urothelial carcinoma (UTUC) following radical cystectomy (RC) remain incompletely defined, which has limited the ability to individualize postoperative surveillance. MATERIALS AND METHODS: A retrospective review of 2 institutional registries was performed to identify patients undergoing RC for urothelial carcinoma. Multivariable Cox proportional hazard models for metachronous post-RC UTUC were developed in one institutional data set and validated in the second institutional data set. A post-RC UTUC risk score was then developed from these models. RESULTS: A total of 3,170 RC patients were included from the training cohort and 959 RC patients from the validation cohort. At a median followup after RC of 4.6 years (IQR 2.1-8.7), 167 patients were diagnosed with UTUC. On multivariable analysis in the training cohort, risk factors for metachronous UTUC were the presence of positive urothelial margin (HR 2.60, p <0.01), history of bacillus Calmette-Guérin treatment prior to RC (HR 2.20, p <0.01), carcinoma in situ at RC (HR 2.01, p <0.01) and pre-RC hydronephrosis (HR 1.48, p=0.04). These factors had similar discriminative capacity in the training and validation cohorts (C-statistic 0.71 and 0.73, respectively). A UTUC risk score was developed with these variables which stratified patients into low (0 points), intermediate (1-3 points), and high risk (4+ points) for post-RC UTUC, with respective 5-year UTUC-free survivals of 99%, 96%, 89% in the training cohort and 98%, 96%, and 91% in the validation cohort. CONCLUSIONS: We developed and validated a risk score for post-RC UTUC that may optimize UTUC surveillance protocols after RC.

Contemporary treatment trends for upper urinary tract stones in a total population analysis in Germany from 2006 to 2019: will shock wave lithotripsy become extinct?

PURPOSE: To describe the change in upper urinary tract stone management in Germany over a 14-year period. METHODS: Using remote data processing we analyzed the nationwide German billing data from 2006 to 2019. To analyze the clinics' case numbers and regional trends, we used the reimbursement.INFO tool based on standardized quality reports of all German hospitals. To also cover shock wave lithotripsy (SWL) as an outpatient procedure, we analyzed the research database of the Institute for Applied Health Research with a representative anonymous sample of 4 million insured persons. RESULTS: The number of inpatient interventional therapies for upper tract urolithiasis in Germany increased from 70,099 cases in 2006 to 94,815 cases in 2019 (trend p < 0.0001). In-hospital SWL declined from 41,687 cases in 2006 to 10,724 cases in 2019 (decline of 74%; trend p < 0.0001). The percentage of SWL as an outpatient procedure increased between 2013 and 2018 from 36 to 46% of all performed SWL, while total SWL case numbers declined. Contrarily, the number of ureteroscopies increased from 32,203 cases in 2006 to 78,125 cases in 2019 (increase of 143%; trend p < 0.0001). The number of percutaneous nephrolithotomy also increased from 1673 cases in 2006 to 8937 in 2019 (increase of 434%; trend p < 0.0001). CONCLUSION: We observed an increase in interventional therapy for upper tract urolithiasis in Germany with a dramatic shift from SWL to endoscopic/percutaneous treatment. These changes may be attributed to enormous technological advances of the endoscopic armamentarium and to reimbursement issues.

Natural History of Post-Treatment Kidney Stone Fragments: A Systematic Review and Meta-Analysis.

PURPOSE: We assessed the literature around post-treatment asymptomatic residual stone fragments and performed a meta-analysis. The main outcomes were intervention rate and disease progression. MATERIALS AND METHODS: We searched Ovid®, MEDLINE®, Embase™, the Cochrane Library and ClinicalTrials.gov using search terms: "asymptomatic", "nephrolithiasis", "ESWL", "PCNL", "URS" and "intervention." Inclusion criteria were all studies with residual renal fragments following treatment (shock wave lithotripsy, ureteroscopy or percutaneous nephrolithotomy). Analysis was performed using 'metafor' in R and bias determined using Newcastle-Ottawa scale. RESULTS: From 273 articles, 18 papers (2,096 patients) had details of intervention rate for residual fragments. Aggregate intervention rates for ≤4 mm fragments rose from 19% (20 months) to 22% (50 months), while >4 mm fragments rose from 22% to 47%. Aggregate disease progression rates for ≤4 mm rose from 25% to 47% and >4 mm rose from 26% to 88%. However, there was substantial difference in definition of "disease progression." Meta-analysis comparing >4 mm against ≤4 mm fragments: intervention rate for >4 mm (vs ≤4 mm): OR=1.50 (95% CI 0.70-2.30), p <0.001, I2=67.6%, tau2=0.48, Cochran's Q=11.4 (p=0.02) and Egger's regression: z=3.11, p=0.002. Disease progression rate for >4 mm: OR=0.06 (95% CI -0.98-1.10), p=0.91, I2=53.0%, tau2=0.57, Cochran's Q=7.11 (p=0.07) and Egger's regression: z=-0.75, p=0.45. Bias analysis demonstrated a moderate risk. CONCLUSIONS: Larger post-treatment residual fragments are significantly more likely to require further intervention especially in the long term. Smaller fragments, although less likely to require further intervention, still carry that risk. Notably, there is no significant difference in disease progression between fragment sizes. Patients with residual fragments should be appropriately counselled and informed decision-making regarding further management should be done.

The Impact of Upper Tract Urothelial Carcinoma Diagnostic Modality on Intravesical Recurrence after Radical Nephroureterectomy: A Single Institution Series and Updated Meta-Analysis.

PURPOSE: Diagnostic ureteroscopic biopsy for upper tract urothelial carcinoma (UTUC) has been hypothesized to increase intravesical recurrence of urothelial carcinoma after radical nephroureterectomy (RNU). Moreover, the impact of ureteroscopy without biopsy or percutaneous biopsy on intravesical recurrence remains unknown. Herein, we compared post-RNU intravesical recurrences across UTUC diagnostic modalities. MATERIALS AND METHODS: Patients undergoing RNU at our institution between 1995 and 2019 were categorized by UTUC diagnostic modality: 1) no ureteroscopy or percutaneous biopsy; 2) percutaneous biopsy; 3) ureteroscopy without biopsy; 4) ureteroscopic biopsy. Intravesical recurrences were compared using Kaplan-Meier analyses and Cox-proportional hazard models. Results of group 4 vs 1 were pooled with the literature using a fixed effects meta-analysis. RESULTS: In a cohort of 834 RNU patients, 210 (25.2%) had undergone no ureteroscopy, 57 (6.6%) percutaneous biopsy, 125 (15.0%) ureteroscopy without biopsy, and 442 (53.0%) ureteroscopic biopsy. Two-year intravesical recurrence rates were 15.0%, 12.7%, 18.4%, and 21.9% for groups 1 through 4, respectively (p=0.09). Multivariable analysis found that group 4 had increased intravesical recurrences (HR 1.40, p=0.04) relative to group 1 while group 2 (HR 1.07, p=0.87) and group 3 (HR 1.15, p=0.54) did not. Group 4 remained associated with intravesical recurrence on subset analyses accounting for post-RNU surveillance cystoscopy frequency. On meta-analysis including 11 other series, ureteroscopic biopsy was associated with intravesical recurrence (HR 1.47, p <0.01). CONCLUSIONS: Ureteroscopic biopsy before RNU, but not percutaneous biopsy or ureteroscopy without biopsy, was associated with increased intravesical recurrence. Clinical trials of intravesical chemotherapy after ureteroscopic biopsy are warranted to reduce intravesical recurrences.

An Empirical Study on the Operative Treatment of Symptomatic Urolithiasis in Germany.

PURPOSE: The guidelines of the German, European, and American Urological Associations on urolithiasis advise against general ureteral stenting before and after an uncomplicated ureterorenoscopy (URS). However, German and European guidelines state that stenting prior to URS facilitates stone extraction and reduces intraoperative complications. According to the published literature, German practice seems to deviate from recommendations. This nationwide survey aimed to evaluate the treatment modalities of urolithiasis. METHODS: In November 2018 and March 2019, a total of 199 urological hospital departments in Germany were anonymously surveyed about operative care of symptomatic urolithiasis. The response rate was 72.9%. The survey consisted of 25 questions about diagnostics, surgical technique, and aftercare of the URS. This questionnaire is available in the appendix. RESULTS: A primary URS is performed in ≤10% in 49.6% of the hospitals. In every second urological department (49.7%), the German Diagnosis Related Group (G-DRG) system influences the period of pre-stenting before a secondary URS. After a secondary URS, which is performed in 53.8% of the departments in over 80% of the patients, 14% of the departments omit stenting. The standard for stenting seems to be a 28-cm-long 7 Charrière double-J stent in Germany. CONCLUSION: In Germany, the percentage of primary URS is low, and a ureter stenting is performed in most of the urological departments after URS. Delaying therapy due to economic aspects is the standard in almost half of all urological departments.

Outcomes of ureteroscopy (URS) for stone disease in the paediatric population: results of over 100 URS procedures from a UK tertiary centre.

PURPOSE: To report the outcomes of paediatric ureteroscopy (URS) for stone disease from a specialist endourology centre in the UK. Ureteroscopy for management of stone disease has increased worldwide and is now being done more commonly in the paediatric age group. METHODS: Data were analysed retrospectively from a database maintained between April 2010 and May 2018. Consecutive patients ≤ 16 years of age undergoing semi-rigid or flexible URS for stone disease were included. Stone size and stone-free rate (SFR) were routinely assessed using an ultrasound (USS) and/or plain KUB XR. Complications were graded according to the Clavien-Dindo classification and recorded within 30 days post-procedure and readmissions within 90 days after the procedure were also captured. RESULTS: Over the 8-year period between April 2010 and April 2018, 81 patients with a mean age of 8.8 years (range 18 months-16 years) and a male to female ratio 1:1.1 underwent 102 procedures (1.28 procedure/patient to be stone free). Of the 81 patients, 29 (35.8%) had comorbidities, with 26 (32%) having multiple comorbidities. The mean (± SEM) single and overall stone size was 9.2 mm (± 0.48, range 3-30 mm) and 11.5 mm (± 0.74, range 4-46 mm) respectively, with 22 (27.1%) having multiple stones. Thirty-five (34.7%) had stent in situ pre-operatively. The stone location was in the ureter (26.6%), lower pole (35.4%), and renal pelvis (16.5%), with 22/81(27%) having multiple stones and 21/102 (20.5%) where a ureteral access sheath (UAS) was used. With a mean hospital stay of 1.2 days, the initial and final SFR was 73% and 99%, respectively, and 61/102 (60%) had ureteric stent placed at the end of the procedure. While there were no intra-operative complications, the readmission rate was less than 1% and there were only three early complications recorded. This included a case each of prolonged admission for pain control (grade I), urinary retention (grade II) and post-operative sepsis requiring a brief ITU admission (grade IV). CONCLUSION: Our study demonstrates that in appropriate setting a high stone-free rate can be achieved with minimal morbidity for paediatric patients. There is potentially a need to factor the increasing role of URS in future paediatric urolithiasis guidelines.

[Causes and predictive factors of prolonged length of hospital stay after flexible ureteroscopy: Experience of a large volume institution]. / Causes et facteurs prédictifs d'une hospitalisation postopératoire prolongée après urétéroscopie souple : expérience d'un centre hospitalo-universitaire.

PURPOSE: To identify the causes of prolonged length of hospital stay (LOHS) of patients treated with flexible ureteroscopy (fURS). The secondary endpoint was to identify the predictors of complications. METHODS: A retrospective single-center cohort study was conducted between January 2011 and December 2015. All consecutive patients treated with a planned fURS, regardless of the indication, AND stayed hospitalized for at least one additional day compared to the traditional postoperative LOHS of our center (=1 day) were included. A multivariate analysis was performed to investigate predictive factors of prolonged LOHS. RESULTS: Two hundred and seventy-two patients were included in the final analysis. The median duration of LOHS was two days [2-18]. Forty-seven percent of patients were discharged beyond day 1 and had no complication. Among them, 56% stayed for simple surveillance decided by the surgeon without any specific treatment introduced and 52% stayed for continuation of intravenous preoperative antibiotics. Of the remaining 144 patients who had a complication, 85.4% (123/144) had a minor complication (Clavien 1 or 2). In multivariate analysis, predictive factors of prolonged LOHS (discharge after day 1) were neurological comorbidities (paraplegia, spina bifida, multiple sclerosis) with an odds ratio of 4.39 [1.7; 11.4]. CONCLUSIONS: The causes of prolonged LOHS were mainly related to comorbidities. A number of patients stayed hospitalized without complications. The identification of predictive factors of complications and prolonged LOHS may allow better selection of patients eligible for outpatient surgery and select those for whom inpatient surgery is still recommended. LEVEL OF EVIDENCE: 3.

Psychiatric Diagnoses and Other Factors Associated with Emergency Department Return within 30 Days of Ureteroscopy.

PURPOSE: Emergency department visits after ureteroscopy are costly and inconvenient. To better understand those at risk we aimed to identify patient demographic, medical and surgical factors associated with 30-day emergency department presentation following ureteroscopy for urolithiasis with particular attention to those with a history of a psychiatric diagnosis. MATERIALS AND METHODS: We retrospectively reviewed 1,576 cases (1,395 adults) who underwent stone related ureteroscopy during 3 years at a total of 2 hospitals. We collected patient demographics, medical history and operative details. The primary outcome was return to the emergency department within 30 days of ureteroscopy. Logistic regression was performed to examine factors associated with emergency department presentation. RESULTS: Of the patients 613 (43.9%) had a history of psychiatric diagnosis. Of those with ureteroscopy encounters 12.6% returned to the emergency department within 30 days of ureteroscopy, including 58.8% with a history of psychiatric diagnosis. On multivariable analysis variables associated with emergency department return included a history of psychiatric diagnosis (OR 1.57, p = 0.012), uninsured status (OR 2.46, p = 0.001) and a stone only in the kidney (OR 1.76, p = 0.022). Patients who returned to the emergency department had had more emergency department visits in the year prior to surgery (OR 1.40, p <0.001). On univariable analysis older patients and those with longer operative time were more frequently admitted from the emergency department (OR 1.03, p = 0.002 and OR 1.96, p = 0.03. respectively) while uninsured patients were admitted less frequently (OR 0.19, p = 0.013). No difference was noted in admissions between those with a psychiatric diagnosis and all others (60.7% vs 55.8%, p = 0.48). CONCLUSIONS: We identified factors associated with emergency department return after ureteroscopy, including a history of psychiatric diagnosis, uninsured status and emergency department visits in the year before surgery. These patients may benefit from targeted interventions to help avoid unnecessary emergency department visits.

Clinical and demographic predictors of repeat stone surgery.

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.

Ureteral stenting practices following routine ureteroscopy: an international survey.

PURPOSE: Stent omission after routine ureteroscopy (rtURS) is accepted by current guidelines and may result in decreased patient morbidity and treatment costs. In a value-based healthcare model, the added morbidity and cost of routine stent placement may be scrutinized. Furthermore, data are limited on urologist cost knowledge and it is effect on ureteral stent placement. As such, we seek to describe ureteral stenting practices and urologist cost knowledge amongst US and non-US-based urologists. METHODS: The ureteroscopic practice patterns and cost awareness of members of the Endourological Society were surveyed using an international email listserv. Respondents were grouped by practice location (US vs non-US). Logistic regression was used to evaluate the associations of surgeon practice location with stenting practices. RESULTS: 233 completed responses were received with a response rate of 13.5%. Results revealed that 55% and 71% of respondents reported ureteral stent insertion after rtURS more than 75% of the time for ureteral and renal stones, respectively. Reporting stent insertion following more than 75% of rtURS was more common among US participants for both ureteral and renal stones. Overall, reported cost knowledge was high, but lower among US participants. On multivariable analysis, US respondents were more likely to place ureteral stents after rtURS for ureteral stones more than 75% of the time when compared to those abroad (OR 3.43 p < 0.01). CONCLUSION: Ureteral stenting after rtURS is over utilized in the US compared to other countries. While this phenomenon is multifactorial in nature, cost knowledge may be under recognized as a determinant of ureteral stent placement following rtURS.

Impact of case volume per year on flexible Ureteroscopy practice: an internet based survey.

BACKGROUND: To report current worldwide variation in techniques and clinical practice of flexible ureteroscopy (FURS) among endourologists of different case volumes per year. METHODS: Two invitations to complete an internet survey were emailed to Endourological Society members. Some of survey questions asked about indications of using FURS for renal and upper ureteral stones. Others were concerned with clinical practice of FURS (such as preoperative stenting, use of ureteral access sheath (UAS) and safety guidewire, technique of Laser lithotripsy and fragment retrieval, and post-FURS stenting. Responders were distributed into two groups; high-volume (> 100 cases/year) and low-volume surgeons (< 100 cases/year) and data were compared between both groups. RESULTS: Responses were received from 146 endourologists all over the world (62 high-volume and 84 low-volume). FURS for intrarenal stone > 20 mm was used by 61% of high-volume surgeons compared with 28.6% for low-volume (P < 0.001). Semirigid URS was used for upper ureteric stones in 68% among high-volume group and 82% in low-volume group (P = 0.044). UAS was used by 62% in low-volume group and 69% in high volume group (P = 0.516). Laser stone dusting was preferred by 63% in low-volume group versus 45% by high-volume (P = 0.031). More responders in low-volume group preferred to leave the stent for 6 weeks (P = 0.042). CONCLUSIONS: The use of FURS for treating upper tract calculi has expanded by high volume endourologists to include large renal stones > 20 mm. Low-volume surgeons prefer to use semi-rigid URS for treatment of upper ureteral stones, to apply Laser stone dusting and maintain ureteral stents for longer periods.

A comprehensive literature-based equation to compare cost-effectiveness of a flexible ureteroscopy program with single-use versus reusable devices.

PURPOSE: To critically review all literature concerning the cost-effectiveness of flexible ureteroscopy comparing single-use with reusable scopes. MATERIALS AND METHODS: A systematic online literature review was performed in PubMed, Embase and Google Scholar databases. All factors potentially affecting surgical costs or clinical outcomes were considered. Prospective assessments, case control and case series studies were included. RESULTS: 741 studies were found. Of those, 18 were duplicated and 77 were not related to urology procedures. Of the remaining 646 studies, 59 were considered of relevance and selected for further analysis. Stone free and complication rates were similar between single-use and reusable scopes. Operative time was in average 20% shorter with digital scopes, single-use or not. Reusable digital scopes seem to last longer than optic ones, though scope longevity is very variable worldwide. New scopes usually last four times more than refurbished ones and single-use ureterorenoscopes have good resilience throughout long cases. Longer scope longevity is achieved with Cidex and if a dedicated nurse takes care of the sterilization process. The main surgical factors that negatively impact device longevity are lower pole pathologies, large stone burden and non-use of a ureteral access sheath. We have built a comprehensive fi nancial costeffective decision model to fl exible ureteroscope acquisition. CONCLUSIONS: The cost-effectiveness of a fl exible ureteroscopy program is dependent of several aspects. We have developed a equation to allow a literature-based and adaptable decision model to every interested stakeholder. Disposable devices are already a reality and will progressively become the standard as manufacturing price falls.

Retrograde intrarenal surgery technique without using fluoroscopy and access sheet in the treatment of kidney stones

Background/aim: In this study, we aimed to present our results on single-guidewire flexible ureteroscopy and retrograde intrarenal surgery without fluoroscopy and an access sheet, and to evaluate the efficacy and safety of this procedure retrospectively. Materials and methods: Our routine technique can be described as the evaluation of the ureter using a semirigid ureterorenoscope (URS), leading in the guidewire through the semirigid URS, pulling the semirigid URS back, inserting the flexible URS with the aid of the guidewire, inserting the laser probe through the flexible URS, and performing laser lithotripsy. Results: Our study included 400 male and 198 female patients with a mean age of 36.8 ± 16 (14­80) years. The mean stone size was 8.7 ± 4 (8­20) mm, and the mean operation time was 56 (32­106) min. Postoperative fever was observed in 24 (4%) of the patients, and 30 (5%) patients had hematuria as a minor complication. A stone-free status was observed in 466 (78%) patients, while 102 (17%) patients had clinically insignificant minor stone fragments and 30 patients had clinically significant stone residue. Conclusion: The retrograde intrarenal surgery procedure using only a guidewire without fluoroscopy and an access sheet in the treatment of kidney stones is technically safe and effective.

Variation in Spending around Surgical Episodes of Urinary Stone Disease: Findings from Michigan.

PURPOSE: To help rein in surgical spending there is growing interest in the application of payment bundles to common outpatient procedures like ureteroscopy and shock wave lithotripsy. However, before urologists can move to such a payment system they need to know where episode costs are concentrated. MATERIALS AND METHODS: Using claims data from Michigan Value Collaborative we identified patients who underwent ureteroscopy or shock wave lithotripsy at hospitals in Michigan from 2012 to 2015. We then totaled expenditures for all relevant services during the 30-day surgical episodes of these patients and categorized component payments (ie those for the index procedure, subsequent hospitalizations, professional services and postacute care). Finally we quantified the variation in total episode expenditures for ureteroscopy and shock wave lithotripsy across hospitals, examining drivers of this variation. RESULTS: A total of 9,449 ureteroscopy and 6,446 shock wave lithotripsy procedures were performed at 62 hospitals. Among these hospitals there was threefold variation in ureteroscopy and shock wave lithotripsy spending. The index procedure accounted for the largest payment difference between high vs low cost hospitals (ureteroscopy $7,936 vs $4,995 and shock wave lithotripsy $4,832 vs $3,207, each p <0.01), followed by payments for postacute care (ureteroscopy $2,207 vs $1,711 and shock wave lithotripsy $2,138 vs $1,104, each p <0.01). Across hospitals the index procedure explained 68% and 44% of the variation in episode spending for ureteroscopy and shock wave lithotripsy, and postacute care payments explained 15% and 28%, respectively. CONCLUSIONS: There exists substantial variation in ambulatory surgical spending across Michigan hospitals for urinary stone episodes. Most of this variation can be explained by payment differences for the index procedure and for postacute care services.

The natural history of asymptomatic calyceal stones.

OBJECTIVES: To evaluate the outcomes of patients with incidentally detected asymptomatic calyceal stones on active surveillance, and to identify risk factors for stone-related adverse events (AEs). PATIENTS AND METHODS: In this retrospective case series, we identified all renal units with non-contrast computed tomography diagnosed asymptomatic calyceal stones in a single reference centre between August 2005 and August 2016. Primary endpoints were spontaneous stone passage and need for stone-related surgical intervention. The secondary endpoints were stone-related symptoms and AEs. Cox proportional hazards models were used. RESULTS: We identified 301 renal units from 238 adult patients. The median average age of the study group was 56 years, with two-thirds consisting of males. The mean average cumulative stone size was 10.8 mm. At the end of the study, 58.8% of renal units with stones remained on surveillance with a median follow-up of 63 months. Overall, 26.6% of patients proceeded to surgical intervention with the majority secondary to pain with no stone relocation (30%) or stone relocation to the ureter with or without pain (25%). Over the 5-year period, 14.6% of stones passed spontaneously. On analysis of the secondary endpoints, 39.5% had a stone-related AE (either symptoms and/or need for surgical intervention). Younger patients (aged <50 years), and those with stone growth >1 mm annually were significantly more likely to have an AE (P = 0.012 and P = 0.006, respectively). The risk of an AE during surveillance at 1, 3, and 5 years was 3.4%, 18.9%, and 30.7% respectively. CONCLUSIONS: Long-term conservative approaches for asymptomatic renal stones are an effective management option with ~60% of renal units remaining on active surveillance in >5 years of follow-up. Appropriate counselling with careful patient selection is advocated, as younger patients and those with evidence of stone growth were found to be at greatest risk of an adverse outcome.

Combined Single-Tract of Minimally Percutaneous Nephrolithotomy and Flexible Ureteroscopy for Staghorn Calculi in Oblique Supine Lithotomy Position.

PURPOSE: To present our experience of combined single-percutaneous tract minimally invasive percutaneous nephrolithotomy (MPCNL) and flexible ureteroscopic lithotripsy (FURL) in managing staghorn calculi (SC) in oblique supine lithotomy position and to define the safety, efficiency, and feasibility of this approach. PATIENTS AND METHODS: Eighty-seven patients with SC treated with surgery in our hospital from March 2014 to January 2016 were retrospectively analyzed. The 87 patients were divided into 2 groups according to operative type: MPCNL combined with FURL (Group 1, n = 44) and MPCNL (Group 2, n = 43). The clinical data, perioperative parameters, and postoperative complications of the 2 groups were compared and analyzed. RESULTS: There were no significant differences in age, gender, stone type, and size ( P = .873, .570, .448, and .593, respectively). The average operative time, the average hospitalization time after surgery, the hemoglobin level, and the complication rate of Group 1 were lower than that of Group 2 ( P < .05 each). The first and second time stone free rates of Group 1 were higher than that of Group 2 ( P < .05 each). CONCLUSION: Single-tract MPCNL combined with FURL in the oblique supine lithotomy position to treat SC could improve stone free rates, reduce operative time and length of hospital stay, decrease renal hemorrhage, and avoid other complications. We think this is an efficient and safe operative approach to manage SC.

Ureteroscopy and stone treatment in the elderly (≥70 years): prospective outcomes over 5- years with a review of literature.

OBJECTIVE: To assess outcomes of ureteroscopy for treatment of stone disease in the elderly. Ureteroscopy (URS) is an increasingly popular treatment modality for urolithiasis and its applications are ever expanding with the development of newer technologies. Its feasibility and outcomes within the elderly population to our knowledge remain under-reported. MATERIALS AND METHODS: We examined the patient demographics and surgical outcomes from our prospective database for patients ≥70 years who underwent URS for urolithiasis, in a 5-year period between March 2012 and December 2016. RESULTS: A total of 110 consecutive patients underwent 121 procedures (1.1 procedure/ patient) with a mean age of 77.2 years (range: 70-91 years). Stone location was in the kidney/ pelviureteric junction (PUJ) in 29%, ureter in 37% and in multiple locations in 34%. The initial and final stone free rate (SFR) was 88% and 97% respectively. While 73% were done as true day case procedures, 89% patients were discharged within 24 hours. Eleven patients (9%) underwent complications of which 10 were Clavien I/II including acute urinary retention, urinary tract infection, stent symptoms and pneumonia. One patient underwent Clavien IV complication where they needed intensive care unit admission for urosepsis but fully recovered and were discharged home subsequently. CONCLUSION: Ureteroscopy is a safe and effective method of managing urolithiasis in elderly patients. Although most patients are discharged within 24-hours, consideration needs to be made for patients where social circumstances can impact their discharge planning.

Impact of diagnostic ureteroscopy on intravesical recurrence in patients undergoing radical nephroureterectomy for upper tract urothelial cancer: a systematic review and meta-analysis.

Aim of this study was to analyse the association between the use of diagnostic ureteroscopy (URS) and the development of intravesical recurrence (IVR) in patients undergoing radical nephroureterectomy (RNU) for high-risk upper tract urothelial carcinoma. A systematic review of the published data was performed up to December 2016, using multiple search engines to identify eligible studies. A formal meta-analysis was conducted of studies comparing patients who underwent URS before RNU with those who did not. Hazard ratios (HRs), with their 95% confidence intervals (CIs), from each study were used to calculate pooled HRs. Pooled estimates were calculated using a fixed-effects or random-effects model according to heterogeneity. Statistical analyses were performed using RevMan, version 5. Seven studies were included in the systematic review, but only six of these were deemed fully eligible for meta-analysis. Among the 2 382 patients included in the meta-analysis, 765 underwent diagnostic URS prior to RNU. All examined studies were retrospective, and the majority examined Asian populations. The IVR rate ranged from 39.2% to 60.7% and from 16.7% to 46% in patients with and without prior URS, respectively. In the pooled analysis, a statistically significant association was found between performance of URS prior to RNU and IVR (HR 1.56, 95% CI 1.33-1.88; P < 0.001). There was no heterogeneity in the observed outcomes, according to the I2 statistic of 2% (P = 0.40). Within the intrinsic limitations of this type of analysis, these findings suggest a significant association between the use of diagnostic URS and higher risk of developing IVR after RNU. Further research in this area should be encouraged to further investigate the possible causality behind this association and it potential clinical implications.

Ureteroscopy for Stone Disease in Paediatric Population is Safe and Effective in Medium-Volume and High-Volume Centres: Evidence from a Systematic Review.

PURPOSE OF REVIEW: The incidence of urinary stone disease among the paediatric population is increasing. Whilst there has been a rise in the number of original studies published on ureteroscopy (URS) in children, critical review still remains under-reported. RECENT FINDINGS: A Cochrane style systematic review was performed to identify all original articles on URS (minimum of 25 cases) for stone disease in paediatric patients between Jan. 1996 and Dec. 2016. Based on the number of reported cases, centres were divided into medium (25-49 cases) and high (≥ 50 cases) volume studies. Thirty-four studies (2758 children) satisfied our search criteria and were included in this review. The mean stone size was 8.6 mm with an overall stone-free rate (SFR) of 90.4% (range 58-100). Medium-volume centres reported a mean SFR of 94.1% (range 87.5-100), whilst high-volume centres reported a mean SFR of 88.1% (range 58-98.5). Mean number of sessions to achieve stone-free status in medium-volume and high-volume groups was 1.1 and 1.2 procedures/patient respectively. The overall complication rate was 11.1% (327/2994). Breakdown by Clavien grade was as follows: Clavien I 69% and Clavien II/III 31%. There were no Clavien IV/V complications, and no mortality was recorded across any of the studies. The overall failure to access rate was 2.5% (76/2944). Medium-volume and high-volume studies had overall complication rates of 6.9% (37/530) and 12.1% (287/2222) respectively, but there was no significant difference in major or minor complications between these two groups. Ureteroscopy is a safe and effective treatment for paediatric stone disease. Medium-volume centres can achieve equally high SFRs and safety profiles as high-volume centres. Despite the rarity of paediatric stone disease, our findings might increase the uptake of paediatric URS procedures.