A quantitative analysis of voiding cystourethrogram features confirms the association between high-grade vesicoureteral reflux with male sex, younger age, and hydronephrosis.

INTRODUCTION: Vesicoureteral reflux (VUR) is commonly diagnosed in the workup of urinary tract infections or hydronephrosis in children. Traditionally, VUR severity is graded subjectively based on voiding cystourethrogram (VCUG) imaging. Herein, we characterized the association between age, sex, and indication for VCUG, by employing standardized quantitative features. METHODS: We included renal units with a high certainty in VUR grade (>80% consensus) from the qVUR model validation study at our institution between 2013 and 2019. We abstracted the following variables: age, sex, laterality, indication for VCUG, and qVUR parameters (tortuosity, ureter widths on VCUG). High-grade VUR was defined as grade 4 or 5 The association between each variable and VUR grade was assessed. RESULTS: A total of 443 patients (523 renal units) were included, consisting of a 48:52 male/female ratio. The median age at VCUG was 13 months. Younger age at VCUG (<6 months) was associated with greater odds of severe VUR (odds ratio [OR] 2.0), and there was a weak correlation between age and VUR grade (ρ=-0.17). Male sex was associated with increased odds of high-grade VUR (OR 2.7). VCUGs indicated for hydronephrosis were associated with high-grade VUR (OR 4.1) compared to those indicated for UTI only. Ureter tortuosity and width were significantly associated with each clinical variable and VUR severity. CONCLUSIONS: Male sex, younger age (<6 months), and history of hydronephrosis are associated with both high-grade VUR and standardized quantitative measures, including greater ureter tortuosity and increased ureteral width. This lends support to quantitative assessment to improve reliability in VUR grading.

Nephron-sparing surgery for renal cell carcinoma in children and young adults: A systematic review.

OBJECTIVE: To determine the patient characteristics and role of nephron-sparing surgery (NSS) in the treatment of children and young adults with renal cell carcinoma (RCC). METHODS: A systematic search of Embase, MEDLINE, and Scopus databases was conducted in December 2021 according to Cochrane collaboration recommendations. All included manuscripts were assessed for patient characteristics and all reported outcomes for patients undergoing partial nephrectomy (PN), and radical nephrectomy (RN) outcomes were abstracted as a comparison group. Primary outcomes included surgical outcomes, overall survival, kidney outcomes. Outcomes were pooled with weighted mean and ranges. Meta-analysis was not performed given study quality. This systematic review was prospectively registered on PROSPERO (CRD42022300261). RESULTS: We found a total of 16 studies describing 119 and 559 unique patients undergoing PN and RN, respectively, with a mean age of 12.2 years and mean follow-up of 59.1 months. The mean tumor size for patients undergoing PN was 3.5 cm. Of the 113 patients undergoing PN with available data, 109 were alive at follow-up (98%). No studies reported long-term kidney outcomes, and four studies reported surgical outcomes. All studies had at least moderate risk of bias. CONCLUSIONS: The use of NSS in children and young adults with RCC is feasible in selected patients. However, small sample sizes, confounding, and low study quality limit clinical recommendation on NSS in this population. There are significant opportunities for future research on the use of NSS in RCC, especially with systematic reporting of oncological, kidney, and surgical outcomes.

The effect of primary urinary diversion on kidney function in posterior urethral valve: A matched comparison.

OBJECTIVE: To determine long-term kidney outcomes in boys with posterior urethral valve (PUV) undergoing either primary valve ablation or urinary diversion with matched baseline kidney function. METHODS: After retrospective review of patients managed for PUV at our institution, propensity score matched analysis was conducted using nadir serum creatinine with logistic regression analysis. Nearest neighbor matching was used to allocate boys to primary urinary diversion and primary ablation groups. Primary outcomes included kidney function by creatinine or estimated glomerular filtration rate, chronic kidney disease, and end-stage renal disease. Comparative statistics by odds ratio (OR) and hazard ratios on survival analysis were calculated. RESULTS: A total of 21 boys undergoing primary diversion were matched with 42 boys undergoing ablation using nadir serum creatinine and follow-up time with a median follow-up of 4.8 years. After matching, there was no significant difference in last follow-up kidney function by creatinine (P = .99) or estimated glomerular filtration rate (P = .98). Primary diversion was not associated with increased likelihood of developing chronic kidney disease stage 3 (OR 1.33; P = .31) or end-stage renal disease (OR 1.88; P = .35 and hazard ratios 1.85; P = .30) compared to primary ablation. CONCLUSIONS: Our propensity matched study suggests that long-term kidney function and kidney outcomes are similar between primary ablation and primary diversion after adjusting for baseline kidney function in boys with PUV.

Multi-institutional Validation of Improved Vesicoureteral Reflux Assessment With Simple and Machine Learning Approaches.

PURPOSE: Vesicoureteral reflux grading from voiding cystourethrograms is highly subjective with low reliability. We aimed to demonstrate improved reliability for vesicoureteral reflux grading with simple and machine learning approaches using ureteral tortuosity and dilatation on voiding cystourethrograms. MATERIALS AND METHODS: Voiding cystourethrograms were collected from our institution for training and 5 external data sets for validation. Each voiding cystourethrogram was graded by 5-7 raters to determine a consensus vesicoureteral reflux grade label and inter- and intra-rater reliability was assessed. Each voiding cystourethrogram was assessed for 4 features: ureteral tortuosity, proximal, distal, and maximum ureteral dilatation. The labels were then assigned to the combination of the 4 features. A machine learning-based model, qVUR, was trained to predict vesicoureteral reflux grade from these features and model performance was assessed by AUROC (area under the receiver-operator-characteristic). RESULTS: A total of 1,492 kidneys and ureters were collected from voiding cystourethrograms resulting in a total of 8,230 independent gradings. The internal inter-rater reliability for vesicoureteral reflux grading was 0.44 with a median percent agreement of 0.71 and low intra-rater reliability. Higher values for each feature were associated with higher vesicoureteral reflux grade. qVUR performed with an accuracy of 0.62 (AUROC=0.84) with stable performance across all external data sets. The model improved vesicoureteral reflux grade reliability by 3.6-fold compared to traditional grading (P < .001). CONCLUSIONS: In a large pediatric population from multiple institutions, we show that machine learning-based assessment for vesicoureteral reflux improves reliability compared to current grading methods. qVUR is generalizable and robust with similar accuracy to clinicians but the added prognostic value of quantitative measures warrants further study.

Is Stone-free Status After Surgical Intervention for Kidney Stones Associated With Better Health-related Quality of Life? - A Multicenter Study From the North American Stone Quality of Life Consortium.

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

Evaluation of a Single-Use Flexible Cystoscope: A Multi-Institutional International Study.

Introduction: Acquisition costs and prohibitively expensive technical support for endoscope maintenance, repair, and reprocessing have deterred adoption of flexible cystoscopes by many urologists internationally. This study evaluated the performance of a novel single-use digital cystoscope that can directly connect to a laptop or computer monitor for visualization, obviating the need for a tower. Materials and Methods: The performance characteristics of flexible single-use cystoscopes (NeoScope) were prospectively evaluated vs a reusable flexible cystoscope (Olympus) in three clinical cases and two independent benchtop testing episodes in Canada. Cystoscope maneuverability, imaging, deflection, irrigation, and ease of use of instrumentation were investigated. Additional investigations were performed during clinical use in Zimbabwe (7 patients), Egypt (10 patients), and Dominica (5 patients). Results: Bench testing revealed smaller tip diameter (4.06 vs 6.09 mm) and shorter (35.4 vs 38 cm) single-use cystoscopes vs reusable cystoscopes. Deflection of the single-use scope was superior with an empty working channel (230 up/220 down) vs the reusable (195 up/95 down) but showed a more substantial decrease in deflection on placement of instruments including a grasper. Clinical use revealed satisfactory maneuverability, ease of use of instruments, deflection, and visualization. Conclusions: Benchtop testing performance of the single-use digital flexible cystoscopes was inferior compared with reusable digital cystoscopes. However, these single-use endoscopes offer adequate illumination, imaging, and maneuverability. Direct connection to any computer monitor allowed truly portable use, allowing for treatment of patients in a variety of clinical settings without the need for ancillary equipment.

Evaluating collagenase Clostridium histolyticum administration protocols in the treatment of Peyronie's disease.

PURPOSE OF REVIEW: Treatment of Peyronie's disease with collagenase Clostridium histolyticum (CCh) has gained world-wide adoption following the phase III clinical trials IMPRESS I and II. However, the optimal treatment parameters remain largely unknown. Many groups have made modifications to CCh treatment in Peyronie's disease in recent years. This review aims to discuss the variations in CCh treatment reported and associated outcomes. RECENT FINDINGS: Variations in CCh treatment protocols include administering higher CCh doses (0.9 mg) less frequently (q1month), use of home penile modeling, use of angulating penile traction devices, and vacuum therapy devices. Authors have reported different injection techniques to include three-point fans and tunneling techniques. Patient selection has expanded to include and evaluate responses among men with some extent of plaque calcification, and ventral curves. SUMMARY: Since publication of the IMPRESS trials, several variations of CCh treatment have been reported with similar treatment responses to the original trials. However, future studies are required with prospective, randomized comparative designs to identify the optimal treatment strategies for men with Peyronie's disease.

Total Surface Area Influences Stone Free Outcomes in Shock Wave Lithotripsy for Distal Ureteral Calculi.

Introduction: Current American Urological Association guidelines recommend ureteroscopy (URS) as primary management of distal ureteral stones and shock wave lithotripsy (SWL) as a secondary option. Utilization of SWL in the management of nephrolithiasis in North America has decreased. We hypothesized that SWL continues to be an effective option in the management of distal ureteral calculi and studied data from our center in patients who received SWL for distal ureteral stones. Methods: A retrospective review was performed of 104 patients treated initially with SWL for distal ureteral calculi between 2011 and 2018 at this institution. The success rate of SWL was assessed through radiologic imaging and if subsequent procedures were required to render patients stone free. Results: Operative note and chart review identified 104 patients who presented with distal ureteral stones and were treated with SWL as the initial form of management. Average patient age was 52.2 ± 15.3 years, average BMI was 27.4 ± 5.7, and average total axial stone surface area was 25.96 ± 14.32 mm2. Of these patients, 78.8% (n = 82) were stone free following one SWL and required no subsequent procedures. Of these patients, 87.5% (n = 91) were stone free following a second SWL, and 87.5% (n = 91) were stone free following a secondary URS. After the initial SWL, residual stones were identified in 21.2% of patients (n = 22). Four patients, 3.8%, required a salvage URS following a failed second SWL to achieve stone-free status. Conclusion: One SWL procedure offers a stone-free rate (SFR) of 78.8% and after two SWLs an 87.5% SFR. Only 12.5% of patients undergoing SWL at our center required URS to achieve a stone-free status. SWL is an effective modality in the treatment of distal ureteral stones.

Single-Use Flexible Ureteroscopes: How Do They Compare with Reusable Ureteroscopes?

Flexible ureteroscopy has become an important tool in the urologist's armamentarium. Until recently, reusable ureteroscopes were the only tools available to perform ureteroscopy. However, in recent years, single-use flexible and semirigid ureteroscopes have been developed as an alternative to reusable ureteroscopes. These disposable ureteroscopes were designed to mitigate problems associated with the use of reusable ureteroscopes, including the high costs related to ureteroscope acquisition, maintenance, processing, sterilization, and repairs. In this review, we provide an overview of currently available single-use flexible ureteroscopes, which include LithoVue, Uscope, NeoFlex, and Shaogang, as well as the Neoscope semirigid ureteroscope. The functional capabilities (deflection, irrigation, and optical properties) of each ureteroscope are also discussed.