The relationship between the force applied and perceived by the surgeon during ureteral access sheath placement: ex-vivo experimental model.

PURPOSE: To define a peak force of insertion (PFOI) threshold for ureteral damage during ureteral access sheath (UAS) placement on an experimental ureteral orifice model. METHODS: A specially designed water tank using 2 laparoscopic 5 mm ports and 2 different size (10 Fr and 8 Fr) sealing cap adaptors (SCA) as ureteral orifices was used to perform the test. A 10-12 Fr UAS was fixed to a load cell and the force of insertion (FOI) was continuously recorded with a digital force gauge.13 experts in the field of endourology who participated performed 3 UAS insertions. The FOI was recorded initially with 10 Fr followed by 8 Fr SCA. On the final insertion, the orifice was obstructed, leaving a 5 cm length to insert the UAS. The experts were asked to "Stop at the point they anticipate ureteral damage, and they would not proceed in real life". RESULTS: Using 10 Fr SCA the PFOI was 2.12 ± 0.58 Newton (N) (range:1.48-3.48) while 8 Fr SCA showed a PFOI 5.76 ± 0.96 N (range:4.05-7.35). Six of the experts, said they would stop proceeding when they reached above 5.1 N. Three experts had PFOI < 5.1 N and the other 4 stated they would go with PFOIs of 5.88, 6.16, 6.69 and 7.35 N when using SCA of 8 Fr.The highest load they would stop proceeding had a PFOI of 6.09 ± 1.87 N (range: 2.53-10.74). CONCLUSION: The PFOI threshold for ureteral damage inserting UAS of the experts is variable. Although FOI is a subjective perception, experience suggests that ureteral injury may occur at an average of 6.05 N perceived by surgeons' tactile feedback. In-vivo measurement of UAS PFOI may confirm a threshold.

In vitro investigation of stone ablation efficiency, char formation, spark generation, and damage mechanism produced by thulium fiber laser.

To investigate stone ablation characteristics of thulium fiber laser (TFL), BegoStone phantoms were spot-treated in water at various fiber tip-to-stone standoff distances (SDs, 0.5 ~ 2 mm) over a broad range of pulse energy (Ep, 0.2 ~ 2 J), frequency (F, 5 ~ 150 Hz), and power (P, 10 ~ 30 W) settings. In general, the ablation speed (mm3/s) in BegoStone decreased with SD and increased with Ep, reaching a peak around 0.8 ~ 1.0 J. Additional experiments with calcium phosphate (CaP), uric acid (UA), and calcium oxalate monohydrate (COM) stones were conducted under two distinctly different settings: 0.2 J/100 Hz and 0.8 J/12 Hz. The concomitant bubble dynamics, spark generation and pressure transients were analyzed. Higher ablation speeds were consistently produced at 0.8 J/12 Hz than at 0.2 J/100 Hz, with CaP stones most difficult yet COM and UA stones easier to ablate. Charring was mostly observed in CaP stones at 0.2 J/100 Hz, accompanied by strong spark-generation, explosive combustion, and diminished pressure transients, but not at 0.8 J/12 Hz. By treating stones in parallel fiber orientation and leveraging the proximity effect of a ureteroscope, the contribution of bubble collapse to stone ablation was found to be substantial (16% ~ 59%) at 0.8 J/12 Hz, but not at 0.2 J/100 Hz. Overall, TFL ablation efficiency is significantly better at high Ep/low F setting, attributable to increased cavitation damage with less char formation.

International Alliance of Urolithiasis guideline on retrograde intrarenal surgery.

OBJECTIVES: To set out the second in a series of guidelines on the treatment of urolithiasis by the International Alliance of Urolithiasis that concerns retrograde intrarenal surgery (RIRS), with the aim of providing a clinical framework for urologists performing RIRS. MATERIALS AND METHODS: After a comprehensive search of RIRS-related literature published between 1 January 1964 and 1 October 2021 from the PubMed database, systematic review and assessment were performed to inform a series of recommendations, which were graded using modified GRADE methodology. Additionally, quality of evidence was classified using a modification of the Oxford Centre for Evidence-Based Medicine Levels of Evidence system. Finally, related comments were provided. RESULTS: A total of 36 recommendations were developed and graded that covered the following topics: indications and contraindications; preoperative imaging; preoperative ureteric stenting; preoperative medications; peri-operative antibiotics; management of antithrombotic therapy; anaesthesia; patient positioning; equipment; lithotripsy; exit strategy; and complications. CONCLUSION: The series of recommendations regarding RIRS, along with the related commentary and supporting documentation, offered here should help provide safe and effective performance of RIRS.

Initial Longitudinal Outcomes of Risk-Stratified Men in Their Forties Screened for Prostate Cancer Following Implementation of a Baseline Prostate-Specific Antigen.

PURPOSE: Prostate cancer (PCa) screening can lead to potential over-diagnosis/over-treatment of indolent cancers. There is a need to optimize practices to better risk-stratify patients. We examined initial longitudinal outcomes of mid-life men with an elevated baseline prostate-specific antigen (PSA) following initiation of a novel screening program within a system-wide network. MATERIALS AND METHODS: We assessed our primary care network patients ages 40 to 49 years with a PSA measured following implementation of an electronic health record screening algorithm from 2/2/2017-2/21/2018. The multidisciplinary algorithm was developed taking factors including age, race, family history, and PSA into consideration to provide a personalized approach to urology referral to be used with shared decision-making. Outcomes of men with PSA ≥1.5 ng/mL were evaluated through 7/2021. Statistical analyses identified factors associated with PCa detection. Clinically significant PCa (csPCa) was defined as Gleason Grade Group (GGG) ≥2 or GGG1 with PSA ≥10 ng/mL. RESULTS: The study cohort contained 564 patients, with 330 (58.5%) referred to urology for elevated PSA. Forty-nine (8.7%) underwent biopsy; of these, 20 (40.8%) returned with PCa. Eleven (2.0% of total cohort and 55% of PCa diagnoses) had csPCa. Early referral timing (odds ratio [OR], 4.58) and higher PSA (OR, 1.07) were significantly associated with PCa at biopsy on multivariable analysis (both p<0.05), while other risk factors were not. Referred patients had higher mean PSAs (2.97 vs. 1.98, p=0.001). CONCLUSIONS: Preliminary outcomes following implementation of a multidisciplinary screening algorithm identified PCa in a small, important percentage of men in their forties. These results provide insight into baseline PSA measurement to provide early risk stratification and detection of csPCa in patients with otherwise extended life expectancy. Further follow-up is needed to possibly determine the prognostic significance of such mid-life screening and optimize primary care physician-urologist coordination.

International Alliance of Urolithiasis Guideline on Shockwave Lithotripsy.

Different international associations have proposed their own guidelines on urolithiasis. However, the focus is primarily on an overview of the principles of urolithiasis management rather than step-by-step technical details for the procedure. The International Alliance of Urolithiasis (IAU) is releasing a series of guidelines on the management of urolithiasis. The current guideline on shockwave lithotripsy (SWL) is the third in the IAU guidelines series and provides a clinical framework for urologists and technicians performing SWL. A total of 49 recommendations are summarized and graded, covering the following aspects: indications and contraindications; preoperative patient evaluation; preoperative medication; prestenting; intraoperative analgesia or anesthesia; intraoperative position; stone localization and monitoring; machine and energy settings; intraoperative lithotripsy strategies; auxiliary therapy following SWL; evaluation of stone clearance; complications; and quality of life. The recommendations, tips, and tricks regarding SWL procedures summarized here provide important and necessary guidance for urologists along with technicians performing SWL. PATIENT SUMMARY: For kidney and urinary stones of less than 20 mm in size, shockwave lithotripsy (SWL) is an approach in which the stone is treated with shockwaves applied to the skin, without the need for surgery. Our recommendations on technical aspects of the procedure provide guidance for urologists and technicians performing SWL.

Initial Safety and Feasibility of Steerable Ureteroscopic Renal Evacuation: A Novel Approach for the Treatment of Urolithiasis.

Background: There is a need to reliably render urolithiasis patients completely stone free with minimal morbidity. We report on the initial safety and feasibility with steerable ureteroscopic renal evacuation (SURE) in a prospective study using basket extraction as a comparison. Materials and Methods: A pilot randomized controlled study was conducted comparing SURE with basket extraction postlaser lithotripsy. SURE is performed using the CVAC™ Aspiration System, a steerable catheter (with introducer). The safety and feasibility of steering CVAC throughout the collecting system under fluoroscopy and aspirating stone fragments as it was designed to do were evaluated. Fluoroscopy time, change in hemoglobin, adverse events through 30 days, total and proportion of stone volume removed at 1 day, intraoperative stone removal rate, and stone-free rate (SFR) at 30 days through CT were compared. Results: Seventeen patients were treated (n = 9 SURE, n = 8 Basket). Baseline demographics and stone parameters were not significantly different between groups. One adverse event occurred in each group (self-limiting ileus for SURE and urinary tract infection for Basket). No mucosal injury and no contrast extravasation were observed in either group. The CVAC catheter was steered throughout the collecting system and aspirated fragments. There was no significant difference in fluoroscopy time, procedure time, change in hemoglobin, or stone removal rate between groups. SURE removed more and a greater proportion of stone volume at day 1 vs baskets (202 mm3 vs 91 mm3, p < 0.01 and 84% vs 56%, p = 0.022). SURE achieved 100% SFR at 30 days vs 75% for baskets, although this difference was not statistically significant (p = 0.20). Conclusions: This initial study suggests SURE is safe, feasible, and may be more effective in stone removal postlaser lithotripsy compared to basketing. More development is needed, and larger clinical studies are underway.

Comparison of Different Pulse Modulation Modes for Holmium:Yttrium-Aluminum-Garnet Laser Lithotripsy Ablation in a Benchtop Model.

Introduction: Manipulation of Holmium:Yttrium-Aluminum-Garnet laser parameters such as pulse energy (PE), frequency, and duration can impact laser lithotripsy ablation efficiency. In 2017, Lumenis introduced Moses™ Technology, which uses pulse modulation to enhance the delivery of energy from fiber to stone as well as to minimize stone retropulsion. Since the introduction of Moses Technology, other companies have brought additional pulse modulation concepts to market. The purpose of this in vitro study is to compare the pulse characteristics and stone ablation efficiency of Lumenis Moses Technology with Quanta's Vapor Tunnel™. Materials and Methods: Submerged BegoStone phantoms were systematically ablated using either the Lumenis Moses Pulse 120H or the Quanta Litho 100 clinical laser system. Two PEs (0.4 and 1 J), three fiber-stone standoff distances (SDs) (0.5, 1, 2 mm), and all available pulse duration and modulation modes for each laser were tested in combination. Fiber speed was adjusted to scan across the stone surface at either 1 or 10 pulses/mm to form single pulse craters or an ablation trough, respectively. Volumes of single craters and 1 mm trough segments were imaged and quantified using optical coherence tomography. Results: Ablation volumes decreased with decreasing PE and increasing SD. Statistically significant variability was seen between pulse types (PT) at every tested parameter set. Among pulse modulation modes, Moses Distance (MD) was superior at 0.5 mm in all testing and at 2 mm in trough testing. Vapor Tunnel (VT) was superior in 2 mm single crater testing. All modulated pulses performed similarly at 1 mm. Conclusions: In this benchtop model of laser lithotripsy, stone ablation was significantly impacted by PT. MD demonstrated superior or noninferior stone ablation at most tested parameters. VT maintained its efficacy the best as SD increased. Future work should focus on the mechanistic differences of these modes relative to other traditional laser pulse modes.

Evolution of Single-Use Urologic Endoscopy: Benchtop and Initial Clinical Assessment of a New Single-Use Flexible Cystoscope.

Introduction: Office cystoscopy is one of the most frequently performed procedures by a urologist. However, single-use cystoscopes remain quite undeveloped. Ambu® has developed single-use broncoscopes, rhinolaryngoscopes, and duodenoscopes. Recently, they released a single-use cystoscope. In this study, we performed a benchtop and an initial clinical assessment of the Ambu aScope™ (4) Cysto (aS4C) single-use cystoscope. Materials and Methods: Ten new, never-used aS4C single-use cystoscopes were assessed for optical performance, maximal tip flexion, and irrigation flow rate with empty working channel, 365 µm laser fiber, 0.035 in hydrophilic-tipped wire, 1.9F nitinol basket, and a 1.8 mm flexible stent grasper. All cystoscopes were then fully flexed 25 times in each direction, and maximal flexion angles were remeasured with and without instruments. Optical resolution, distortion, and depth of field were measured and compared with our reusable digital flexible cystoscopes. Assessment of clinical use was performed for inpatient bedside procedures using a Likert feedback survey and the NASA Task Load Index. Results: Maximal upward flexion exceeded 200° and 160° for all working instruments in upward and downward flexion. Downward flexion demonstrated different flexion between instrument groups in pre- and postcycling (p < 0.001). There was no clinical difference between the pre- and postcycling flexion. Flow rate decreased with increasing working instrument size (p < 0.001). The Olympus HD cystoscope resolution was superior at 3 and 5 mm distance, but not at other distances. The Ambu scope was superior to the Olympus SD scope at all distances except 3 mm. The aS4C had higher Likert scale survey scores for clinical use. Conclusions: The new Ambu single-use cystoscope demonstrates good flexion across instruments and comparable optics with reusable cystoscopes. In addition, initial inpatient bedside use of the aS4C and Monitor system compares favorably with the Olympus reusable cystoscope. Further testing in clinical scenarios such as hematuria, urothelial carcinoma, and operative endoscopy is warranted.

Benchtop Assessment of a New Single-Use Flexible Ureteroscope.

Introduction: Single-use flexible ureteroscopes are an increasingly popular alternative to reusable ureteroscopes. In this study, we performed a benchtop examination of the physical and optical properties of the new Dornier Axis™ (Webling, Germany) single-use ureteroscope. Methods: Ten new, never-used Dornier Axis ureteroscopes were assessed for optical performance, maximal tip deflection, and irrigation flow rate with an empty working channel and with insertion of 200 and 365 µm laser fibers, and a 1.9F nitinol basket. All ureteroscopes were then fully deflected 100 times in each direction, and maximal deflection angles were re-measured with and without instruments in the working channel. All measurements were performed in duplicate. In vitro optical testing for resolution, image distortion, and depth of field was performed and compared vs the LithoVue™ (Boston Scientific, Marlborough, MA) single-use ureteroscope. Statistical analyses using paired Wilcoxon rank-sum tests and Kruskal-Wallis multiple-group comparison tests were performed in R. Results: Median maximal deflection angles exceeded 300° in both directions before and after 100 full deflection cycles for all groups except the 365 µm laser fiber group. After 100 deflection cycles, there was no change in the majority of working instruments, except a decrease in upward flexion with an empty channel and 200 µm Moses™ laser fiber, and downward flexion with 200 µm Flexiva™ laser fiber (all <10°). After excluding the 365 µm fiber, there was no difference in multi-group comparison for upward and downward flexion pre- and post-cycling. Median flow rate through an empty channel was 48.0 mL/min, and it decreased significantly with all used instruments (p < 0.001). Compared with the LithoVue, the Axis demonstrated superior resolution at all tested distances and less distortion. Conclusions: The new Dornier Axis single-use ureteroscope demonstrates excellent tip deflection, which remains unchanged after 100 manual flexions in each direction. The Axis also demonstrates superior optical performance compared with the LithoVue in benchtop testing.

Evaluation of a Novel Single-Use Flexible Ureteroscope.

Introduction: A novel single-use flexible ureteroscope promises the optical characteristics and maneuverability of a reusable fourth-generation flexible ureteroscope. In this study, the LithoVue Single-Use Digital flexible ureteroscope was directly compared with contemporary reusable flexible ureteroscopes, with regard to optics, deflection, and irrigation flow. Methods: Three flexible ureteroscopes such as the LithoVue (Single Use; Boston Scientific), Flex-Xc (Karl Storz, Germany), and Cobra (Richard Wolf, Germany) were assessed in vitro for image resolution, distortion, color representation, grayscale imaging, field of view, and depth of field. Ureteroscope deflection was tested with an empty channel followed by placement of a 200 µm laser fiber and a 1.9F wire basket, a 2.0F nanoelectric pulse lithotripsy (NPL) probe, and a 2.4F NPL probe. Ureteroscope irrigation flow was measured using normal saline at 100 cm, with an empty channel followed by a 200 µm laser fiber, a 1.9F wire basket and a 2.0F NPL probe. Results: The LithoVue showed the largest field of view, with excellent resolution, image distortion, and depth of field. No substantial difference was demonstrated in color reproducibility or in the discernment of grayscales between ureteroscopes. The LithoVue maintained full deflection ability with all instruments in the working channel, although the Flex-Xc and Cobra ureteroscopes showed loss of deflection ranging from 2° to 27°, depending on the instrument placed. With an empty channel, the LithoVue showed an absolute flow rate similar to the Flex-Xc ureteroscope (p = 0.003). It maintained better flow with instruments in the channel than the Flex-Xc ureteroscope. The Cobra ureteroscope has a separate 3.3F instrument channel, keeping flow rates the same with instrument insertion. Conclusion: The LithoVue Single-Use Digital ureteroscope has comparable optical capabilities, deflection, and flow, making it a viable alternative to standard reusable fourth-generation flexible digital and fiberoptic ureteroscopes.

Implementation and Impact of a Risk-Stratified Prostate Cancer Screening Algorithm as a Clinical Decision Support Tool in a Primary Care Network.

BACKGROUND: Implementation methods of risk-stratified cancer screening guidance throughout a health care system remains understudied. OBJECTIVE: Conduct a preliminary analysis of the implementation of a risk-stratified prostate cancer screening algorithm in a single health care system. DESIGN: Comparison of men seen pre-implementation (2/1/2016-2/1/2017) vs. post-implementation (2/2/2017-2/21/2018). PARTICIPANTS: Men, aged 40-75 years, without a history of prostate cancer, who were seen by a primary care provider. INTERVENTIONS: The algorithm was integrated into two components in the electronic health record (EHR): in Health Maintenance as a personalized screening reminder and in tailored messages to providers that accompanied prostate-specific antigen (PSA) results. MAIN MEASURES: Primary outcomes: percent of men who met screening algorithm criteria; percent of men with a PSA result. Logistic repeated measures mixed models were used to test for differences in the proportion of individuals that met screening criteria in the pre- and post-implementation periods with age, race, family history, and PSA level included as covariates. KEY RESULTS: During the pre- and post-implementation periods, 49,053 and 49,980 men, respectively, were seen across 26 clinics (20.6% African American). The proportion of men who met screening algorithm criteria increased from 49.3% (pre-implementation) to 68.0% (post-implementation) (p < 0.001); this increase was observed across all races, age groups, and primary care clinics. Importantly, the percent of men who had a PSA did not change: 55.3% pre-implementation, 55.0% post-implementation. The adjusted odds of meeting algorithm-based screening was 6.5-times higher in the post-implementation period than in the pre-implementation period (95% confidence interval, 5.97 to 7.05). CONCLUSIONS: In this preliminary analysis, following implementation of an EHR-based algorithm, we observed a rapid change in practice with an increase in screening in higher-risk groups balanced with a decrease in screening in low-risk groups. Future efforts will evaluate costs and downstream outcomes of this strategy.

Evaluation and Medical Management of Patients with Cystine Nephrolithiasis: A Consensus Statement.

Purpose: Cystinuria is a genetic disorder with both autosomal recessive and incompletely dominant inheritance. The disorder disrupts cystine and other dibasic amino acid transport in proximal tubules of the kidney, resulting in recurrent kidney stone formation. Currently, there are no consensus guidelines on evaluation and management of this disease. This article represents the consensus of the author panel and will provide clinicians with a stepwise framework for evaluation and clinical management of patients with cystinuria based on evidence in the existing literature. Materials and Methods: A search of MEDLINE®/PubMed® and Cochrane databases was performed using the following key words: "cystine nephrolithiasis," "cystinuria," "penicillamine, cystine," and "tiopronin, cystine." In total, as of May 2018, these searches yielded 2335 articles, which were then evaluated for their relevance to the topic of evaluation and management of cystinuria. Evidence was evaluated by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Results: Twenty-five articles on the topic of cystinuria or cystine nephrolithiasis were deemed suitable for inclusion in this study. The literature supports a logical evaluation process and step-wise treatment approach beginning with conservative measures: fluid intake and dietary modification. If stone formation recurs, proceed to pharmacotherapeutic options by first alkalinizing the urine and then using cystine-binding thiol drugs. Conclusions: The proposed clinical pathways provide a framework for efficient evaluation and treatment of patients with cystinuria, which should improve overall outcomes of this rare, but highly recurrent, form of nephrolithiasis.

Avoiding a Lemon: Performance Consistency of Single-Use Ureteroscopes.

INTRODUCTION AND OBJECTIVES: Single-use flexible ureteroscopes are increasingly popular because of high repair costs of reusable ureteroscopes. As new single-use ureteroscopes enter the market, the consistency of performance of these devices has been questioned. Our objective was to compare two single-use ureteroscopes: the Pusen PU3022a (Zhuhai Pusen) and the LithoVue (Boston Scientific) with emphasis on physical and optical performance consistency. METHODS: Ten LithoVue and 10 Pusen ureteroscopes were evaluated in never-used condition. The following parameters were recorded: maximal tip deflection with an empty working channel, 200 µm laser fiber, and 1.9F basket; image resolution at 10, 20, and 50 mm; and irrigation flow rate; all ureteroscopes were then fully deflected for 200 cycles. Maximum deflection was remeasured. Mean values for each parameter were compared. To examine within-manufacturer consistency, the variance was calculated and an F-test performed to evaluate for equivalence. RESULTS: Both ureteroscopes provided max deflection over 270°. The Pusen flexed to a greater degree than LithoVue. The Pusen lost more deflection with a laser fiber in the working channel. LithoVue had higher resolution at 10 mm, but the ureteroscopes were similar at 20 and 50 mm. Although the working channel diameter is identical, irrigation flow was higher with the Pusen. However, its working channel was 7 cm shorter than LithoVue. After 200 cycles of deflections, LithoVue had less deflection loss, although one ureteroscope was excluded from analysis because of mechanical failure. Variability was minimal and not significant between manufacturers at all measured parameters. CONCLUSIONS: LithoVue and the newer PU3022a have similar "out-of-the-box" performance characteristics and seem durable. These two single-use flexible ureteroscopes performed consistently regardless of the manufacturer.

Let's Get to the Point: Comparing Insertion Characteristics and Scope Damage of Flat-Tip and Ball-Tip Holmium Laser Fibers.

INTRODUCTION: A ball-tip holmium laser fiber (TracTip; Boston Scientific) has been developed to theoretically reduce damaging friction forces generated within a ureteroscope working channel. We compared the insertional forces and damage with a ureteroscope inner lining when inserting standard flat-tip and ball-tip laser fibers. MATERIALS AND METHODS: A standard ureteroscope channel liner was placed in a 3D-printed plastic mold. Molds were created at four angles of deflection (30°, 45°, 90°, and 180°) with a 1 cm radius of curvature. New 200 µm ball-tip (TracTip; Boston Scientific) and 200 µm flat-tip (Flexiva; Boston Scientific) laser fibers were advanced through the liner using a stage controller. A strain gauge was used to measure force required for insertion. Each fiber was passed 600 times at each angle of deflection. The ureteroscope liner was changed every 150 passes. Leak testing was performed every 50 passes or when the insertional force increased significantly to assess damage to the liner. RESULTS: At all deflection angles, the average insertional force was significantly lower with the ball-tip laser fibers compared with flat-tip laser fibers (p < 0.001). All trials with the ball-tip lasers were completed at each angle without any leaks. Two of four trials using flat-tip fibers at 45° deflection caused liner leaks (at 91 and 114 passes). At 90° deflection, all flat-tip trials caused liner leaks on first pass. The 180° trials could not physically be completed with the flat-tip laser fiber. Within the flat- and ball-tip groups, an increasing amount of force was needed to pass the fiber as the degree of deflection increased (p < 0.001). CONCLUSIONS: The ball-tip holmium laser fiber can be safely passed through a deflected ureteroscope without causing liner perforation. The standard flat-tip fiber requires greater insertion force at all angles and can cause the ureteroscope liner to leak if it is deflected 45° or more.

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.

Antibiotic Utilization Before Endourological Surgery for Urolithiasis: Endourological Society Survey Results.

INTRODUCTION: Ureteroscopy (URS) and percutaneous nephrolithotomy (PCNL) are common procedures performed to treat kidney stones. Despite advances in technology/technique, serious infectious complications can occur. To better understand the preoperative antibiotic administration patterns and adherence to guidelines from the American Urological Association (AUA) and the European Association of Urology (EAU), members of the Endourological Society were sent a clinical vignette-based survey to assess the antibiotic use in a variety of pre-URS and pre-PCNL scenarios. METHODS: Endourological Society members were e-mailed a survey that queried antibiotic therapy duration before uncomplicated URS and PCNL with negative and asymptomatic positive preoperative urine cultures (PUCs). For negative PUC questions, selecting more perioperative antibiotics was considered a "prolonged" course as it extends past the maximum of 24-hour perioperative prophylaxis recommended by both the AUA and EAU. RESULTS: The response rate was 16.3% for a total of 326 responders. Twenty-one percent to 39% of respondents reported giving prolonged courses of preoperative antibiotics before a URS or PCNL with a negative PUC (p < 0.0001). When presented with a negative PUC, more prolonged antibiotic courses were reported with the following hierarchy: PCNL for 2 cm intrarenal stones (39%) > URS for 12 mm renal pelvis stone (28%) > URS for 7 mm distal ureteral stones (21%) (p < 0.0001). In both negative and positive PUC questions, differences were noted in preoperative antibiotic prescribing patterns among site of practice (United States, Canada, Europe, Asia, South America, and Others), type of practice (academic vs all others), years in practice (<10 or ≥10 years), and surgical volume (URS and PCNL >100 or ≤100 annual cases). CONCLUSIONS: Adherence to guidelines on antibiotic administration before PCNL and URS with a negative PUC varies by scenario and provider. In 21% to 39% of negative PUC cases, reported antibiotic use before a URS or PCNL is not consistent with recommendations from the AUA and EAU. Before a positive PUC URS or PCNL, nearly all surveyed provide preoperative antibiotics; however, the regimen length is variable.

Disproportionate Use of Inpatient Care by Older Adults With Kidney Stones.

OBJECTIVE: To describe variation in utilization and costs of inpatient care for patients with kidney stones, examining associations with older age. MATERIALS AND METHODS: Using the Nationwide Inpatient Sample we examined inpatient discharges with stone diagnoses from 2007 to 2011. We examined length of stay, hospitalization cost, and postdischarge care utilization using multivariable regression to identify associations between patient/hospital characteristics and resource. RESULTS: An estimated 1.7 million hospital discharges for stone disease occurred during the study period. Median length of stay was 2.1 days with a median cost of $6300. Hospital use was substantially higher among persons ≥65 years old (older adults) as compared to those aged 18-64 (younger adults): median length of stay was 3.1 days, with 25% staying more than 5.9 days. Older adults were significantly more likely to utilize home health (odds ratio [OR] 3.6) or skilled nursing (OR 5.0) after discharge. Older adults accounted for 1 in 3 hospital discharges, 40% of costs, and half of postdischarge care utilization. They were more likely to be septic during hospitalization (OR 1.8) which doubled costs per episode, but less likely to receive surgery (OR 0.93). CONCLUSION: While historically at lower risk for kidney stones compared to younger adults, older adults utilizing inpatient care account for a disproportionate share of the economic burden of disease. Utilization is higher for older adults across multiple dimensions, including hospital costs, length of stay, and postdischarge care. These findings suggest that efforts to understand and mitigate the impact of kidney stones on this vulnerable population are required.

Subcapsular Splenic Urinoma and Splenorenal Fistula: A New Complication of Percutaneous Nephrolithotomy.

Background: Splenic urinoma has not been previously reported as a complication of percutaneous nephrolithotomy (PNL). Case Presentation: A 46-year-old Caucasian male underwent PNL for two large left renal stones. Surgery was performed in prone split-leg position, with access obtained through combined fluoroscopic guidance and direct ureteroscopic observation of the targeted calix. The tract was dilated to 30F using a pressure balloon, and complete clearance of stones was obtained through a combination of rigid and flexible nephroscopy, as well as antegrade ureteroscopy. The patient was left with a Double-J ureteral stent on a string for removal in 1 week. After overnight observation, his hemoglobin, white blood cell count, and renal function were normal and thus he was discharged home. The day after stent removal, he presented to the emergency department with abdominal pain, was found to have mild left hydronephrosis on CT, and was discharged on 1 week of antibiotics. One week later he re-presented with worsening abdominal pain and was found to have an elevated creatinine and a white blood cell count of 21 × 109/L. On contrasted CT with delayed images, an 18 cm splenic fluid collection was seen with a fistulous connection to the left kidney collecting system. He underwent emergent stent placement and improved clinically without drainage of the urinoma. A renal ultrasonography 1 month after stent placement confirmed resolution of the splenic urinoma, so the stent was removed at 1 month. Follow-up CT 1 month after stent removal was normal without any evidence of fistula or urinoma recurrence. Conclusion: This is the first report of a subcapsular splenic urinoma and splenorenal fistula post-PNL. Ureteral stent placement was sufficient for drainage and to resolve the complication.

Next-Generation Single-Use Ureteroscopes: An In Vitro Comparison.

INTRODUCTION: Single-use ureteroscopes have been gaining popularity in recent years. We compare the optics, deflection, and irrigation flow of two novel single-use flexible ureteroscopes-the YC-FR-A and the NeoFlex-with contemporary reusable and single-use flexible ureteroscopes. METHODS: Five flexible ureteroscopes, YC-FR-A (YouCare Tech, China), NeoFlex (Neoscope, Inc., USA), LithoVue (Boston Scientific, USA), Flex-Xc (Karl Storz, Germany), and Cobra (Richard Wolf, Germany), were assessed in vitro for image resolution, distortion, field of view, depth of field, color representation, and grayscale imaging. Ureteroscope deflection and irrigation were also compared. RESULTS: The YC-FR-A showed a resolution of 5.04 lines/mm and 4.3% image distortion. NeoFlex showed a resolution of 17.9 lines/mm and 14.0% image distortion. No substantial difference was demonstrated regarding the other optic characteristics between the two. Across all tested ureteroscopes, single-use or reusable, the digital scopes performed best with regard to optics. The YC-FR-A had the greatest deflection at baseline, but lacks two-way deflection. The NeoFlex had comparable deflection at baseline to reusable devices. Both ureteroscopes had substantial loss of deflection with instruments in the working channel. The YC-FR-A had the greatest irrigation rate. The NeoFlex has comparable irrigation to contemporary ureteroscopes. CONCLUSIONS: The YouCare single-use fiberoptic flexible ureteroscope and NeoFlex single-use digital flexible ureteroscope perform comparably to current reusable ureteroscopes, possibly making each a viable alternative in the future. Newer YouCare single-use flexible ureteroscopes with a digital platform and two-way deflection may be more competitive, while the NeoFlex devices are undergoing rapid improvement as well. Further testing is necessary to validate the clinical performance and utility of these ureteroscopes, given the wide variety of single-use devices under development.