Maternal family history of urolithiasis is associated with earlier age of onset of stone disease.

PURPOSE: To evaluate the impact of detailed family history on the severity of disease and age of onset in patients with urolithiasis. METHODS: Prospectively collected data from a single institution between October 2015 and December 2020 were analyzed. Our primary endpoint was the number of patients experiencing at least one recurrent stone during the follow-up period. RESULTS: Of 1566 patients analyzed, 603 (39%) reported at least one family member with a history of stones. The percentage of patients experiencing at least one recurrent stone event was higher in patients with a family history of stones (38%) compared to those without a family history of stones (28%) over a median follow-up period of 8 months (p = 0.001). On multivariate analysis, the presence of any family history of urolithiasis increased risk of recurrent stone events (odds ratio [OR] 1.62, p < 0.001). The presence of both a first- and a second-degree relative with urolithiasis was associated with higher odds for a recurrent stone event (OR 2.17; p = 0.003) and a younger age of onset for stones, (OR 3.32; < 0.001). A maternal-side relative with stones conferred a higher odds ratio for younger age of first onset of stones (OR 2.93; p < 0.001). CONCLUSION: Any family history of kidney stone disease imparts an increased risk of recurrent stone event and an earlier age of onset for urolithiasis. The presence of both first- and second-degree relatives or a maternal-side relative with kidney stones may be a predictor for an earlier age of onset for urolithiasis.

Laparoscopic transperitoneal adrenalectomy in the large adrenal tumor from single center experience.

BACKGROUND: The role of laparoscopic adrenalectomy (LA) in a large adrenal tumor is controversial due to the risk of malignancy and technical difficulty. In this study, we compared the perioperative outcomes and complications of LA on large (≥ 6 cm) and (< 6 cm) adrenal tumors. METHODS: We retrospectively reviewed all clinical data of patients who underwent unilateral transperitoneal LA in our institution between April 2000 and June 2019. Patients were classified by tumor size into 2 groups. Patients in group 1 had tumor size < 6 cm (n = 408) and patient in group 2 had tumor size ≥ 6 cm (n = 48). Demographic data, perioperative outcomes, complications, and pathologic reports were compared between groups. RESULTS: Patients in group 2 were significant older (p = 0.04), thinner (p = 0.001) and had lower incident of hypertension (p = 0.001), with a significantly higher median operative time (75 vs 120 min), estimated blood loss (20 vs 100 ml), transfusion rate (0 vs 20.8%), conversion rate (0.25 vs 14.6%) and length of postoperative stays ( 4 vs 5.5 days) than in group 2 (all p < 0.001). Group 2 patients also had significantly higher frequency of intraoperative complication (4.7 vs 31.3%; adjust Odds Ratio [OR] = 9.67 (95% CI 4.22-22.17), p-value < 0.001) and postoperative complication (5.4 vs 31.3%; adjust OR = 5.67 (95% CI 2.48-12.97), p-value < 0.001). Only eight (1.8%) major complications occurred in this study. The most common pathology in group 2 patient was pheochromocytoma and metastasis. CONCLUSIONS: Laparoscopic transperitoneal adrenalectomy in large adrenal tumor ≥ 6 cm is feasible but associated with significantly worse intraoperative complications, postoperative complications, and recovery. However, most of the complications were minor and could be managed conservatively. Careful patient selection with the expert surgeon in adrenal surgery is the key factor for successful laparoscopic surgery in a large adrenal tumor. TRIAL REGISTRATION: This study was retrospectively registered in the Thai Clinical Trials Registry on 02/03/2020. The registration number was TCTR20200312004.

Fatty acid-binding protein 4 downregulation drives calcification in the development of kidney stone disease.

Nephrolithiasis is a significant source of morbidity, and its incidence has increased significantly over the last decades. This rise has been attributed to concurrent increasing rates of obesity, associated with a 3-time risk of developing NL. To date, the mechanism by which obesity is linked to stone formation has not been elucidated. We aimed to utilize a transcriptomics approach to discover the missing link between these two epidemic diseases. We investigated gene expression profiling of nephrolithiasis patients by two RNA-sequencing approaches: comparison between renal papilla tissue with and without the presence of calcified Randall's plaques (RP), and comparison between the papilla, medulla, and cortex regions from within a single recurrent stone forming kidney. Results were overlaid between differently expressed genes found in the patient cohort and in the severely lithogenic kidney to identify common genes. Overlay of these two RNA-sequencing datasets demonstrated there is impairment of lipid metabolism in renal papilla tissue containing RP linked to downregulation of fatty acid binding protein (FABP) 4. Immunohistochemistry of human kidney specimens and microarray analysis of renal tissue from a nephrolithiasis mouse model confirmed that FABP4 downregulation is associated with renal stone formation. In a FABP4 knockout mouse model, FABP4 deficiency resulted in development of both renal and urinary crystals. Our study revealed that FABP4 plays an important, previously unrecognized role in kidney stone formation, providing a feasible mechanism to explain the link between nephrolithiasis and metabolic syndrome.

Low Income and Nonwhite Race are Strongly Associated with Worse Quality of Life in Patients with Nephrolithiasis.

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 (ß = 0.372, p = 0.014), as were nonwhite race (ß = -0.299, p = 0.001), unemployed work status (ß = -0.291, p = 0.008), female gender (ß = -0.204, p <0.001), body mass index greater than 40 kg/m2 (ß = -0.380, p <0.001), 5 or more medical comorbidities (ß = -0.354, p = 0.001), severe recurrent stone formation (ß = -0.146, p = 0.045), enrollment at an acute care visit, or a preoperative or postoperative appointment (ß = -0.548, p <0.001) and recent stone symptoms (ß = -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.

The Urological Association of Asia clinical guideline for urinary stone disease.

The Urological Association of Asia, consisting of 25 member associations and one affiliated member since its foundation in 1990, has planned to develop Asian guidelines for all urological fields. The field of stone diseases is the third of its guideline projects. Because of the different climates, and social, economic and ethnic environments, the clinical practice for urinary stone diseases widely varies among the Asian countries. The committee members of the Urological Association of Asia on the clinical guidelines for urinary stone disease carried out a surveillance study to better understand the diversity of the treatment strategy among different regions and subsequent systematic literature review through PubMed and MEDLINE database between 1966 and 2017. Levels of evidence and grades of recommendation for each management were decided according to the relevant strategy. Each clinical question and answer were thoroughly reviewed and discussed by all committee members and their colleagues, with suggestions from expert representatives of the American Urological Association and European Association of Urology. However, we focused on the pragmatic care of patients and our own evidence throughout Asia, which included recent surgical trends, such as miniaturized percutaneous nephrolithotomy and endoscopic combined intrarenal surgery. This guideline covers all fields of stone diseases, from etiology to recurrence prevention. Here, we present a short summary of the first version of the guideline - consisting 43 clinical questions - and overview its key practical issues.

Feasibility of Antegrade Contrast-enhanced US Nephrostograms to Evaluate Ureteral Patency.

Purpose To demonstrate the feasibility of contrast material-enhanced ulrasonographic (US) nephrostograms to assess ureteral patency after percutaneous nephrolithotomy (PCNL) in this proof-of-concept study. Materials and Methods For this HIPAA-compliant, institutional review board-approved prospective blinded pilot study, patients undergoing PCNL provided consent to undergo contrast-enhanced US and fluoroscopic nephrostograms on postoperative day 1. For contrast-enhanced US, 1.5 mL of Optison (GE Healthcare, Oslo, Norway) microbubble contrast agent solution (perflutren protein-type A microspheres) was injected via the nephrostomy tube. Unobstructed antegrade ureteral flow was defined by the presence of contrast material in the bladder. Contrast-enhanced US results were compared against those of fluoroscopic nephrostograms for concordance. Results Ten studies were performed in nine patients (four women, five men). Contrast-enhanced US demonstrated ureteral patency in eight studies and obstruction in two. One patient underwent two studies, one showing obstruction and the second showing patency. Concordance between US and fluoroscopic assessments of ureteral patency was evaluated by using a Clopper-Pearson exact binomial test. These results were perfectly concordant with fluoroscopic nephrostogram results, with a 95% confidence interval of 69.2% and 100%. No complications or adverse events related to contrast-enhanced US occurred. Conclusion Contrast-enhanced US nephrostograms are simple to perform and are capable of demonstrating both patency and obstruction of the ureter. The perfect concordance with fluoroscopic results across 10 studies demonstrated here is not sufficient to establish diagnostic accuracy of this technique, but motivates further, larger scale investigation. If subsequent larger studies confirm these preliminary results, contrast-enhanced US may provide a safer, more convenient way to evaluate ureteral patency than fluoroscopy. © RSNA, 2016 Online supplemental material is available for this article.

Contrast Enhanced Ultrasound as a Radiation-Free Alternative to Fluoroscopic Nephrostogram for Evaluating Ureteral Patency.

PURPOSE: We compared contrast enhanced ultrasound and fluoroscopic nephrostography in the evaluation of ureteral patency following percutaneous nephrolithotomy. MATERIALS AND METHODS: This prospective cohort, noninferiority study was performed after obtaining institutional review board approval. We enrolled eligible patients with kidney and proximal ureteral stones who underwent percutaneous nephrolithotomy at our center. On postoperative day 1 patients received contrast enhanced ultrasound and fluoroscopic nephrostogram within 2 hours of each other to evaluate ureteral patency, which was the primary outcome of this study. RESULTS: A total of 92 pairs of imaging studies were performed in 82 patients during the study period. Five study pairs were excluded due to technical errors that prevented imaging interpretation. Females slightly predominated over males with a mean ± SD age of 50.5 ± 15.9 years and a mean body mass index of 29.6 ± 8.6 kg/m2. Of the remaining 87 sets of studies 69 (79.3%) demonstrated concordant findings regarding ureteral patency for the 2 imaging techniques and 18 (20.7%) were discordant. The nephrostomy tube was removed on the same day in 15 of the 17 patients who demonstrated antegrade urine flow only on contrast enhanced ultrasound and they had no subsequent adverse events. No adverse events were noted related to ultrasound contrast injection. While contrast enhanced ultrasound used no ionizing radiation, fluoroscopic nephrostograms provided a mean radiation exposure dose of 2.8 ± 3.7 mGy. CONCLUSIONS: A contrast enhanced ultrasound nephrostogram can be safely performed to evaluate for ureteral patency following percutaneous nephrolithotomy. This imaging technique was mostly concordant with fluoroscopic findings. Most discordance was likely attributable to the higher sensitivity for patency of contrast enhanced ultrasound compared to fluoroscopy.

Using an abdominal phantom to teach urology residentes ultrasound-guided percutaneous needle placement.

INTRODUCTION: To assess the effect of a hands-on ultrasound training session to teach urologic trainees ultrasound-guided percutaneous needle placement. MATERIALS AND METHODS: University of California, San Francisco (UCSF) urology residentes completed a time trial, placing a needle into a phantom model target under ultrasound guidance. Participants were randomized into three educational exposure groups: Group 1's time trial occurred prior to any teaching intervention, group 2's after experiencing a hands-on training module, and group 3's after exposure to both the training module and one-on-one attending feedback. Needle placement speed and accuracy as well as trainees' perceived confidence in utilizing ultrasound were measured. RESULTS: The study cohort consisted of 15 resident trainees. Seven were randomized to group 1, three to group 2, and five to group 3. All residents reported minimal prior ultrasound experience. Their confidence in using ultrasound improved significantly after completing the training module with the most significant improvement seen among junior residents. Time to needle placement was fastest after receiving attending feedback (46.6sec in group 3 vs. 82.7sec in groups 1 and 2, p<0.01). Accuracy also improved with attending feedback, though the number of repositioning attempts did not differ significantly between groups. CONCLUSIONS: A hands-on training module and use of an abdominal phantom trainer increased resident confidence and skill in their use of ultrasound to guide percutaneous needle positioning. Attending feedback is critical for improving accuracy in needle guidance toward a target. Ultrasound-guided needle positioning is a teachable skill and can be applicable to multiple urologic procedures.

Leiomyosarcoma of the renal pelvis diagnosed by percutaneous endoscopic resection.

We present a case of leiomyosarcoma arising from the renal pelvis, which is a rare clinical entity. A percutaneous endoscopic resection led to the final histopathological diagnosis. The patient underwent radical nephrectomy and did not receive adjuvant therapy. Based on follow-up CT scans, he remains recurrence-free one year after surgery.

Ultrasound-guided Access and Dilation for Percutaneous Nephrolithotomy in the Supine Position: A Step-by-Step Approach.

INTRODUCTION: Ultrasound guidance for percutaneous nephrolithotomy (PCNL) has gained acceptance amongst urologists given its numerous advantages over fluoroscopy. While traditionally performed in the prone position, this video demonstrates a step-by-step approach to performing PCNL in the supine position, solely under ultrasound guidance. MATERIALS AND METHODS: Once in the modified supine (Galdakao-modified Valdivia) position, important anatomic landmarks are identified. It is important to first orient the ultrasound probe such that its cranial side corresponds to the left of the ultrasound screen. After optimizing a target calyx, keeping the needle in the imaging plane of the probe facilitates renal access. Tract dilation under ultrasound guidance is then achieved by keeping the wire and dilators in the same imaging plane. RESULTS: The 11th and 12th ribs, paraspinous muscle, iliac crest, midaxillary line, and costal margin are the anatomic landmarks that orient the probe to the location of the kidney. Placing the ultrasound probe in the midaxillary line, parallel to the 11th rib allows the operator to identify key renal landmarks: the renal cortex, peri-pelvic fat, collecting system, kidney stone with its associated postacoustic shadow, and the intended target calyx. Controlling the needle is easiest in the longitudinal view, as the needle can be visualized from skin to target. Dilation under ultrasound relies on keeping the wire in view. The tip of the 10-French dilator is based on the location where the wire image disappears as the dilator advances. The balloon dilator tip is visualized on ultrasound reaching the appropriate depth just inside the collecting system, at which time balloon inflation results in complete dilation of the tract. CONCLUSIONS: This video provides a step-by-step approach demonstrating that PCNL can be performed in the supine position using only ultrasound-guidance. This approach facilitates renal access in this position and obviates the need for radiation exposure.

Influence of Socioeconomic Factors on Stone Burden at Presentation to Tertiary Referral Center: Data From the Registry for Stones of the Kidney and Ureter.

OBJECTIVE: To determine social factors associated with advanced stone disease (defined as unilateral stone burden >2 cm) at time of presentation to a regional stone referral center. Little is known about social determinants of urolithiasis. We hypothesize that socioeconomic factors impact kidney stone severity at intake to referral centers. METHODS: A retrospective review of the prospectively collected data from the Registry for Stones of the Kidney and Ureter from 2015 to 2018 was conducted to evaluate patient characteristics predictive of having a large (>2 cm) unilateral kidney stone. Data on patient age, gender, body mass index, diabetes, race, language, education level, infection, distance, income, referring regional urologist density, American Society of Anesthesiologists score, and stone analysis were evaluated. RESULTS: Complete imaging and patient variable data was present in 650 of 1142 patients including 197 patients with unilateral stone burden >2 cm. On multivariate analysis, obesity, lower education level, increased distance from the referral center, and symptoms of infection predicted for unilateral stone burden greater than 2 cm. Among 191 patients with stone analysis data present, stone type, income, and urologist density predicted for unilateral stone burden greater than 2 cm. CONCLUSION: In addition to known biological risk factors, patients with lower education levels and from regions of lower mean income were found to be more likely to present to our tertiary care center with stone burden greater than 2 cm. More research is needed to elucidate the social and societal determinants of advanced stone disease and the impact this has on population costs for stone treatment.

Computed Tomography Radiation Exposure Among Referred Kidney Stone Patients: Results from the Registry for Stones of the Kidney and Ureter.

Purpose: Kidney stone patients routinely have CT scans during diagnostic work-up before being referred to a tertiary center. How often these patients exceed the recommended dose limits for occupational radiation exposure of >100 mSv for 5 years and >50 mSv in a single year from CT alone remains unknown. This study aimed to quantify radiation doses from CTs received by stone patients before their evaluation at a tertiary care stone clinic. Methods: From November 2015 to March 2017, consecutive new patients enrolled into the Registry for Stones of the Kidney and Ureter (ReSKU™) had the dose-length product of every available CT abdomen/pelvis within 5 years of their initial visit recorded, allowing for an effective dose (EDose) calculation. Multivariate logistic regression analysis identified factors associated with exceeding recommended dose limits. Models were created to test radiation reducing effects of low-dose and phase-reduction CT protocols. Results: Of 343 noncontrast CTs performed, only 29 (8%) were low-dose CTs (calculated EDose <4 mSv). Among 389 total patients, 101 (26%) and 25 (6%) had an EDose >20 mSv and >50 mSv/year, respectively. Increased body mass index, number of scans, and multiphase scans were associated with exceeding exposure thresholds (p < 0.01). The implementation of a low-dose CT protocol decreased the estimated number of scans contributing to overexposure by >50%. Conclusions: Stone patients referred to a tertiary stone center may receive excessive radiation from CT scans alone. Unnecessary phases and underutilization of low-dose CT protocols continue to take place. Enacting new approaches to CT protocols may spare stone patients from exceeding recommended dose limits.

Ultrasound for Intraoperative Confirmation of Antegrade Ureteral Stent Placement During Laparoscopic Pyeloplasty.

OBJECTIVE: To describe our ultrasound technique for confirming intraoperative, antegrade-placed ureteral stent position during laparoscopic pyeloplasty. BACKGROUND: Disadvantages of retrograde stent placement include the need to reposition the patient into and out of the lithotomy position. Antegrade stent placement can reduce procedure time but requires confirming appropriate distal placement into the bladder with cystoscopy, percutaneous drain placement, or instillation of methylthioninium chloride or indigo carmine. MATERIALS AND METHODS: A 3-way 20-French Foley catheter is placed after induction with general anesthesia. Laparoscopic transperitoneal dismembered pyeloplasty is performed. Intraoperatively, the bladder is filled retrograde with 300ccs normal saline. After completing the posterior suture line of the ureteral anastomosis, a 4.8-French, 26-cm ureteral stent is placed antegrade down the ureter using a 5-French exchange catheter and guidewire. The stent is passed over the guidewire into the bladder. The proximal curl is then placed into the renal pelvis and the anastomosis is completed. Without patient repositioning, an intraoperative bladder ultrasound is performed to identify the distal stent curl within the bladder lumen. RESULTS: This technique demonstrated that ultrasound can guide antegrade stent placement in adult, laparoscopic ureteral surgery. It eliminated the need for intraoperative repositioning of the patient for intraoperative cystoscopy to confirm stent placement and was performed successfully during 8 laparoscopic pyeloplasty cases without failure. Ultrasound is likely more sensitive compared with looking for the presence of vesicoureteral reflux after stent placement, prevents stent malposition, and avoids the use of intravesical dyes that upon reflux can stain tissues and obscure surgical planes. CONCLUSION: Here we demonstrate successful use of intraoperative ultrasound to confirm appropriate distal stent positioning in the bladder of an adult patient following antegrade stent placement for laparoscopic dismembered pyeloplasty. To our knowledge, this has been described in pediatrics, but never in adult patients.

Increasing Body Mass Index Steepens the Learning Curve for Ultrasound-guided Percutaneous Nephrolithotomy.

OBJECTIVE: To define how the learning curve for success in ultrasound-guided percutaneous nephrolithotomy (PCNL) is impacted by body mass index (BMI). Previous research has shown ultrasound-guided PCNL to be an effective method of nephrolithiasis treatment comparable to fluoroscopy-guided PCNL. A common concern for the ultrasound-guided approach is potential imaging difficulty in the obese patient population. METHODS: A prospective cohort study of consecutive patients undergoing PCNL with ultrasound guidance for renal tract access was performed. Clinical data collected included success in gaining renal access with ultrasound guidance, patient BMI, and clinical outcomes over time. Nonparametric LOWESS regression modeling was performed in R using locally weighted scatterplot smoother (R version 3.3.3) for gradations of patients by BMI group (<30, 30-40, and >40). RESULTS: A total of 150 cases were examined. Case number and BMI were evaluated as continuous variables. Multivariate logistic regression revealed that BMI (P = .010; OR 0.93) and case number (P<.001; OR 1.03) were significantly correlated with ultrasound success. Sex, age, hydronephrosis, stone type, puncture location, and stone size did not influence success at obtaining ultrasound-only access in a statistically significant fashion. LOWESS regression modeling of the relationship between case number and renal access success depicts that the curve representative of the BMI >40 group is downward and right-shifted relative to the other two groups. CONCLUSION: The learning curve for successful ultrasound-guided PCNL is impacted by patient's BMI as well as case number. Increasing BMI makes access more challenging when performing ultrasound-guided PCNL.

Clinical Outcomes for Cystinuria Patients with Unilateral Versus Bilateral Cystine Stone Disease.

INTRODUCTION: Cystinuria is a genetic disorder marked by elevated urinary cystine excretion and recurrent cystine nephrolithiasis. Interestingly, despite seemingly similar contralateral renal anatomy, a subset of cystinuric patients consistently form stones in only one kidney. The aim of this study is to evaluate clinical outcomes in unilateral vs bilateral cystine stone formers. PATIENTS AND METHODS: We performed a retrospective case-control study of cystinuric patients evaluated and treated at the University of California, San Francisco between 1994 and 2015 and categorized patients as either unilateral or bilateral stone formers. Clinical presentation, baseline patient demographics, stone procedures, medical therapy regimens, and long-term renal function were compared between the two groups. RESULTS: A total of 42 cystine stone patients (22 female, 20 male) were included in the analysis. The median age at first presentation was 18.5 years and median age at study conclusion was 45.5 years. Two-thirds of patients (n = 28) had a history of bilateral stones, whereas one-third (n = 14) had unilateral stones. Medical therapy regimens were similar between groups. Despite an increased average number of lifetime surgeries (7.5 sessions for bilateral vs 3.7 sessions for unilateral, p < 0.05), there was no significant difference in medians of the most recent glomerular filtration rate when compared with unilateral stone formers (81.5 vs 95 mL/min, respectively; p = 0.28). CONCLUSIONS: The majority of cystinuric patients within our cohort form stones bilaterally during their lifetime, and require more surgical interventions than unilateral stone formers. Despite this, overall renal function is well preserved in unilateral and bilateral cystinuric stone formers treated with minimally invasive stone extraction procedures.

Micro-Costing Analysis Demonstrates Comparable Costs for LithoVue Compared to Reusable Flexible Fiberoptic Ureteroscopes.

INTRODUCTION: Reusable ureteroscope durability and need for repair are significant sources of expense and inefficiency for patients and urologists. Utilization of LithoVue™, a disposable flexible digital ureteroscope, may address some of these concerns. To identify its economic impact on clinical care, we performed a micro-cost comparison between flexible reusable fiberoptic ureteroscopes (URF-P6™) and LithoVue. PATIENTS AND METHODS: For this prospective, single-center micro-costing study, all consecutive ureteroscopies performed during 1 week each in July and August 2016 utilized either URF-P6 or LithoVue ureteroscopes respectively. Workflow data were collected, including intraoperative events, postoperative reprocessing cycle timing, consumables usage, and ureteroscope cost data. RESULTS: Intraoperative data analysis showed mean total operating room time for URF-P6 and LithoVue cases were 93.4 ± 32.3 and 73.6 ± 17.4 minutes, respectively (p = 0.093). Mean cost of operating room usage per case was calculated at $1618.72 ± 441.39 for URF-P6 and $1348.64 ± 237.40 for LithoVue based on institutional cost rates exclusive of disposables. Postoperative data analysis revealed costs of $107.27 for labor and consumables during reprocessing for URF-P6 cases. The costs of ureteroscope repair and capital acquisition for each URF-P6 case were $957.71 and $116.02, respectively. The total ureteroscope cost per case for URF-P6 and LithoVue were $2799.72 and $2852.29, respectively. CONCLUSIONS: Micro-cost analysis revealed that the cost of LithoVue acquisition is higher per case compared to reusable fiberoptic ureteroscopes, but savings are realized in labor, consumables, and repair. When accounting for these factors, the total cost per case utilizing these two ureteroscopes were comparable.

The Morbidity of Ureteral Strictures in Patients with Prior Ureteroscopic Stone Surgery: Multi-Institutional Outcomes.

PURPOSE: Nephrolithiasis is an increasingly common ailment in the United States. Ureteroscopic management has supplanted shockwave lithotripsy as the most common treatment of upper tract stone disease. Ureteral stricture is a rare but serious complication of stone disease and its management. The impact of new technologies and more widespread ureteroscopic management on stricture rates is unknown. We describe our experience in managing strictures incurred following ureteroscopy for upper tract stone disease. MATERIALS AND METHODS: Records for patients managed at four tertiary care centers between December 2006 and October 2015 with the diagnosis of ureteral stricture following ureteroscopy for upper tract stone disease were retrospectively reviewed. Study outcomes included number and type (endoscopic, reconstructive, or nephrectomy) of procedures required to manage stricture. RESULTS: Thirty-eight patients with 40 ureteral strictures following URS for upper tract stone disease were identified. Thirty-five percent of patients had hydronephrosis or known stone impaction at the time of initial URS, and 20% of cases had known ureteral perforation at the time of initial URS. After stricture diagnosis, the mean number of procedures requiring sedation or general anesthesia performed for stricture management was 3.3 ± 1.8 (range 1-10). Eleven strictures (27.5%) were successfully managed with endoscopic techniques alone, 37.5% underwent reconstruction, 10% had a chronic stent/nephrostomy, and 10 (25%) required nephrectomy. CONCLUSIONS: The surgical morbidity of ureteral strictures incurred following ureteroscopy for stone disease can be severe, with a low success rate of endoscopic management and a high procedural burden that may lead to nephrectomy. Further studies that assess specific technical risk factors for ureteral stricture following URS are needed.

Variation in Radiologic and Urologic Computed Tomography Interpretation of Urinary Tract Stone Burden: Results From the Registry for Stones of the Kidney and Ureter.

OBJECTIVE: To compare the measured stone burden recorded between urologists and radiologists, and examine how these differences could potentially impact stone management. As current urologic stone surgery guideline recommendations are based on stone size, accurate stone measurements are crucial to direct appropriate treatment. This study investigated the discrepant interpretation that often exists between urologic surgeons and radiologists' estimation of patient urinary stone burden. MATERIALS AND METHODS: From November 2015 through August 2016, new patients prospectively enrolled into the Registry for Stones of the Kidney and Ureter (ReSKU) were included if they had computed tomography images available and an accompanying official radiologic report at the time of their urologist provider visit. Stone number and aggregate stone size were compared between the urologic interpretation and the corresponding radiologic reports. RESULTS: Of 219 patients who met the inclusion criteria, concordance between urologic and radiologic assessment of aggregate stone size was higher for single stone sizing (63%) compared with multiple stones (32%). Statistical significance was found in comparing the mean difference in aggregate stone size for single and multiple stones (P <.01). Over 33% of stone-containing renal units had a radiologic report with an unclear size estimation or size discrepancy that could lead to non-guideline-driven surgical management. CONCLUSION: Significant variation exists between urologic and radiologic computed tomography interpretations of stone burden. Urologists should personally review patient imaging when considering stone surgical management. A standardized method for measuring and reporting stone parameters is needed among urologists and radiologists.

Identifying factors associated with need for flexible ureteroscope repair: a Western Endourology STone (WEST) research consortium prospective cohort study.

Maintenance of flexible ureteroscopes can involve high costs and administrative burden. Instrument fragility necessitates eventual repair, rendering scopes inaccessible during refurbishment. We conducted a multi-institutional prospective cohort study to identify perioperative factors influencing flexible ureteroscope durability. Patients undergoing flexible ureteroscopy (URS) at six United States endourology centers were enrolled between August 2014 and June 2015. Surgeon self-reported concern and satisfaction with scope performance as well as upward and downward angles of deflection for each scope tip were measured before and after each procedure. The need for scope repair was determined by the operating surgeon at the time of the procedure and recorded. 424 URS cases using 74 flexible ureteroscopes were identified. Scope repair was required in 28 cases (6.6%) involving 26 scopes (35.1%). Upon univariate analysis, shorter patient height, absence of guidewire use, presence of a ureteral access sheath (UAS), longer procedure time, larger stone size, lithotrite type, surgeon training level, and self-reported concern were associated with scope repair. Upon multivariate analysis, UAS use (OR = 2.53, p = 0.005) and degree loss of scope upward flexion during a case (OR = 1.02, p = 0.03) increased the odds of a scope needing repair while the use of safety guidewire decreased the odds of a scope repair (OR = 0.50, p = 0.045). Lithotrite use and surgeon concern were associated with degree loss of scope upward flexion. The use of a UAS, absence of a safety guidewire, and the loss of upward ureteroscope flexion should be considered when evaluating means of optimizing reusable ureteroscope durability.