The Toronto nomogram: A Bayesian meta-regression derived prenatal ultrasound index to predict lower urinary tract obstruction and prune belly syndrome.

INTRODUCTION: A nomogram for predicting the diagnosis of lower urinary tract obstruction (LUTO) based on an antenatal ultrasound index generated from a Bayesian Meta-regression analysis has been in development and noted with superior diagnostic accuracy compared to the keyhole sign (KHS). We aim to assess the accuracy of the nomogram in expanded diagnostic utilization to predict LUTO. METHODOLOGY: The validation of the nomogram for expanded diagnostic utilization was based on data from a prospective institutional antenatal clinic database between January 2020 and June 2022. Diagnostic accuracy indices were determined for confirmed postnatal diagnosis of LUTO or prune belly syndrome (PBS). Receiver operating characteristics (ROC) curves were generated to compare the area under the curve (AUC) of the nomogram versus KHS. RESULTS: Based on 84 male fetuses with antenatal ultrasound of moderate-severe hydronephrosis (PUV n = 15, PBS n = 4), the KHS had 26.3% (95%CI 9.1-51.2) sensitivity and 100% (95%CI 94.4%-100%) specificity, with 14 false-negatives. The nomogram showed a 84.2 (95%CI 60.4%-96.6%) sensitivity and 95.4 (95%CI 87.1%-99%) specificity with three false-positives. The nomogram also had a superior AUC compared to KHS (0.98 vs. 0.63). CONCLUSION: The nomogram can be used as a valuable tool to trigger further postnatal screening and provide individualized risk assessments to families during prenatal counseling.

Implementation of a standardized clinical pathway in a dedicated posterior urethral valves clinic: short-term outcomes.

BACKGROUND: To determine if the implementation of a posterior urethral valves (PUV) clinic and standardized management pathway improves the short-term kidney outcomes of infants with PUV. METHODS: From 2016-2022, 50 consecutive patients were divided into groups after the implementation of the clinic (APUV, n = 29) and before (BPUV, n = 21) during a comparable timeframe. Assessed data included age at initial visit, timing and type of surgery, frequency of follow-up visits, medications, nadir creatinine, and development of CKD/kidney failure. Data are shown as median with interquartile range (IQR) and odds ratios (OR) with 95% confidence interval (CI). RESULTS: APUV had higher rates of prenatal diagnoses (12/29 vs. 1/21; p = 0.0037), earlier initial surgical intervention (8 days; IQR 0, 105 vs. 33 days; IQR 4, 603; p < 0.0001), and higher rates of primary diversions (10/29 vs. 0/21; p = 0.0028). Standardized management led to earlier initiation of alpha blockers (326 days; IQR 6, 860 vs. 991; IQR 149, 1634; p = 0.0019) and anticholinergics (57 days; IQR 3, 860 vs. 1283 days; IQR 477, 1718; p < 0.0001). Nadir creatinine was reached at earlier ages in APUV (105 days; IQR 2, 303 vs. 164 days; IQR 21, 447; p = 0.0192 BPUV). One patient progressed to CKD5 in APUV compared to CKD3, CKD5 and one transplant in BPUV. CONCLUSION: Implementing the PUV clinic with standardized treatment expedited postnatal management and resulted in a higher number of cases detected prenatally, a shift in primary treatment, younger ages at initial treatment, reduced time to nadir creatinine, and timely initiation of supportive medications. A higher resolution version of the Graphical abstract is available as Supplementary information.

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.

Vascular hitch for paediatric pelvi-ureteric junction obstruction with crossing vessels: institutional analysis and systematic review with meta-analysis.

OBJECTIVE: To compare the outcomes for laparoscopic vascular hitch (VH) and dismembered pyeloplasty in patients with pelvi-ureteric junction obstruction (PUJO) secondary to crossing vessels (CV). PATIENTS AND METHODS: Patients who underwent laparoscopic management of CV at our institution were identified between 2008 and 2020. Baseline characteristics and outcome measures were compared between those who underwent VH and those who underwent dismembered pyeloplasty. Those who underwent VH were selected intraoperatively by identifying CV in the absence of intrinsic obstruction by assessing resolution of hydronephrosis after cranially displacing the CV away from the PUJ, followed by intraoperative fluid bolus and diuretic test. In addition, a systematic search and meta-analysis were performed in June 2020 (International Prospective Register of Systematic Reviews [PROSPERO] ID CRD42020195833). RESULTS: A total of 20 patients underwent VH and 74 dismembered pyeloplasty. On multivariate analysis, VH was associated with: shorter operative time (P = 0.001; odds ratio [OR] 0.455, 95% confidence interval [CI] 0.294-0.705) and length of stay (P = 0.012; OR 0.383, 95% CI 0.183-0.803), lower use of stents (P < 0.001; OR 0.024, 95% CI 0.004-0.141) and opioid administration (P = 0.005; OR 0.157, 95% CI 0.044-0.567). From our literature search, 194 records were identified and 18 records were included (three comparative and 16 non-comparative). Meta-analysis of the comparative studies and our institutional data showed similar success rates (relative risk [RR] 1.77, 95% CI 0.33-9.52) and complication rates (RR 0.75, 95% CI 0.20-2.82). VH was associated with shorter operative time (standardised mean difference [SMD] -1.65, 95% CI -2.58 to -0.72 h) and hospital stay (SMD -1.41, 95% CI -2.36 to -0.47 days). The VH success rates ranged from 87.5% to 100% in the identified studies. Failure of VH was associated with unrecognised concomitant intrinsic obstruction in addition to CV. CONCLUSIONS: A VH, for well-selected patients with CV without concomitant intrinsic obstruction, offers a high success rate with shorter operative times.

Pre-versus postnatal presentation of posterior urethral valves: a multi-institutional experience.

OBJECTIVE: To compare the outcomes of pre- vs postnatally diagnosed posterior urethral valves (PUV) at two large paediatric centres in North America to ascertain if the prenatal diagnosis of PUV is associated with better outcomes. PATIENTS AND METHODS: All boys with PUV were identified at two large paediatric institutions in North America between 2000 and 2020 (The Hospital for Sick Children [SickKids, SK] and Children's Hospital of Philadelphia [CHOP]). Baseline characteristics and outcome measures were compared between those diagnosed pre- vs postnatally. Main outcomes of interest included progression of chronic kidney disease (CKD), the need for renal replacement therapy (RRT), and bladder function compromise, as determined by need for clean intermittent catheterisation (CIC). Time-to-event analyses were completed when possible. RESULTS: During the study period, 152 boys with PUV were treated at the SK (39% prenatal) and 216 were treated at the CHOP (71% prenatal). At the SK, there was no difference between the pre- and postnatal groups in the proportion of boys who required RRT, progressed to CKD Stage ≥3, or who were managed with CIC when comparing the timing of diagnosis. The time to event for RRT and CIC was significantly younger for prenatally detected PUV. At the CHOP, significantly more prenatal boys required RRT; however, there was no significant difference in the age this outcome was reached. The proportion of boys managed with CIC was not different but the time to event was significantly earlier in the prenatal group. CONCLUSION: This study represents the largest multi-institutional series of boys with PUV and failed to identify any difference in the outcomes of pre- vs postnatal detection of PUV. A multidisciplinary approach with standardisation of the treatment pathways will help in understanding the true impact of prenatal/early detection on outcomes of PUV.

Personalized application of machine learning algorithms to identify pediatric patients at risk for recurrent ureteropelvic junction obstruction after dismembered pyeloplasty.

PURPOSE: To develop a model that predicts whether a child will develop a recurrent obstruction after pyeloplasty, determine their survival risk score, and expected time to re-intervention using machine learning (ML). METHODS: We reviewed patients undergoing pyeloplasty from 2008 to 2020 at our institution, including all children and adolescents younger than 18 years. We developed a two-stage machine learning model from 34 clinical fields, which included patient characteristics, ultrasound findings, and anatomical variation. We fit and trained with a logistic lasso model for binary cure model and subsequent survival model. Feature importance on the model was determined with post-selection inference. Performance metrics included area under the receiver-operating-characteristic (AUROC), concordance, and leave-one-out cross validation. RESULTS: A total of 543 patients were identified, with a median preoperative and postoperative anteroposterior diameter of 23 and 10 mm, respectively. 39 of 232 patients included in the survival model required re-intervention. The cure and survival models performed well with a leave-one-out cross validation AUROC and concordance of 0.86 and 0.78, respectively. Post-selective inference showed that larger anteroposterior diameter at the second post-op follow-up, and anatomical variation in the form of concurrent anomalies were significant model features predicting negative outcomes. The model can be used at https://sickkidsurology.shinyapps.io/PyeloplastyReOpRisk/ . CONCLUSION: Our ML-based model performed well in predicting the risk of and time to re-intervention after pyeloplasty. The implementation of this ML-based approach is novel in pediatric urology and will likely help achieve personalized risk stratification for patients undergoing pyeloplasty. Further real-world validation is warranted.

Posterior Urethral Valves Outcomes Prediction (PUVOP): a machine learning tool to predict clinically relevant outcomes in boys with posterior urethral valves.

BACKGROUND: Early kidney and anatomic features may be predictive of future progression and need for additional procedures in patients with posterior urethral valve (PUV). The objective of this study was to use machine learning (ML) to predict clinically relevant outcomes in these patients. METHODS: Patients diagnosed with PUV with kidney function measurements at our institution between 2000 and 2020 were included. Pertinent clinical measures were abstracted, including estimated glomerular filtration rate (eGFR) at each visit, initial vesicoureteral reflux grade, and renal dysplasia at presentation. ML models were developed to predict clinically relevant outcomes: progression in CKD stage, initiation of kidney replacement therapy (KRT), and need for clean-intermittent catheterization (CIC). Model performance was assessed by concordance index (c-index) and the model was externally validated. RESULTS: A total of 103 patients were included with a median follow-up of 5.7 years. Of these patients, 26 (25%) had CKD progression, 18 (17%) required KRT, and 32 (31%) were prescribed CIC. Additionally, 22 patients were included for external validation. The ML model predicted CKD progression (c-index = 0.77; external C-index = 0.78), KRT (c-index = 0.95; external C-index = 0.89) and indicated CIC (c-index = 0.70; external C-index = 0.64), and all performed better than Cox proportional-hazards regression. The models have been packaged into a simple easy-to-use tool, available at https://share.streamlit.io/jcckwong/puvop/main/app.py CONCLUSION: ML-based approaches for predicting clinically relevant outcomes in PUV are feasible. Further validation is warranted, but this implementable model can act as a decision-making aid. A higher resolution version of the Graphical abstract is available as Supplementary information.

Omental Procedures During Peritoneal Dialysis Insertion: A Systematic Review and Meta-Analysis.

OBJECTIVES: Peritoneal dialysis (PD) is an option for ultrafiltration for patients with end-stage renal disease. Once placed, PD catheters may malfunction often due to omental wrapping. Omental procedures such as omentectomy and omentopexy may reduce this risk. This investigation aims to perform a systematic review and meta-analysis of the literature on the role of omental procedures on PD catheter insertions. METHODS: Following protocol registration on PROSPERO (CRD42020218950), a systematic review was performed in accordance with the Cochrane Collaboration. A literature search was performed in February 2021 across Medline, EMBASE, Scopus, and Cochrane Library. Records with patients who underwent PD catheter insertion with and without omental manipulation were included. The records underwent screening, full-text review, and data extraction. Study qualities were assessed using RoBINS-I and RoB2. Effect estimates were extracted as risk ratios and corresponding 95% confidence intervals (CI) were pooled using inverse variance method with random-effect model. RESULTS: Of 510 records identified, 15 studies were included in the meta-analysis (1 RCT, 2 prospective, 12 retrospective). With omental procedures, there was decreased the likelihood of failure requiring removal of PD catheter (RR 0.47, 95% CI 0.38, 0.58) and PD catheter obstruction (RR 0.23, 95% CI 0.14, 0.39); there was no difference in likelihood of catheter malposition or migration (RR 0.87, 95% CI 0.23, 3.29) or peritonitis (RR 0.74, 95% CI 0.40, 1.35). CONCLUSION: Based on the current low to moderate quality of evidence, omental manipulation at the time of PD catheter insertion confers benefits of decreased obstruction and failure requiring removal.

Evolving trends in peri-operative management of pediatric ureteropelvic junction obstruction: working towards quicker recovery and day surgery pyeloplasty.

OBJECTIVE: To describe the evolution of practice patterns for pediatric pyeloplasty and determine how these changes have impacted length of stay (LOS), reoperation rates and return emergency department (ER) visits. METHODS: We reviewed our pyeloplasty database from 2008 to 2020 at a quaternary pediatric referral center and we included children 0-18 years undergoing pyeloplasty. Variables captured included: age, sex, baseline and follow-up anteroposterior diameter (APD) and differential renal function (DRF). We also collected data on the use of drains, catheters and/or stents, nausea and vomiting prophylaxis, opioids, regional anesthesia, and non-opioid analgesia. Outcomes were LOS, reoperation rates and ER visits. RESULTS: A total of 554 patients (565 kidneys) were included. Reoperation rate was 7%, redo rate 4% and ER visits 17%. There was a trend towards less opioids, indwelling catheters and internal stents and increasing non-opioid analgesia, externalized stents, and regional anesthesia during the study period. Same-day discharge (SDD) was possible for 88 (16%) children with no differences in reoperation or readmission rates between SDD and admitted (ADM). There was a difference in ER visits (21 [24%] vs. 26 [6%]; p = 0.04) for SDD vs. ADM, respectively. On multivariate analysis, the only predictor of ER visits was younger age. Patients < 7 months were more likely to present to ER (15/41; 37% vs. 6/47, 13%; p = 0.009). Multivariate analysis determined indwelling catheters and opioids were associated with ADM while dexamethasone and ketorolac with SDD. CONCLUSION: Progressive changes in care have contributed to a shorter LOS and increasing rates of SDD for pyeloplasty patients. SDD appears to be feasible and does not result in higher complication rates. These data support the development of a pediatric pyeloplasty ERAS protocol to maximize quicker recovery and foster SDD as a goal.

Predictive accuracy of prenatal ultrasound findings for lower urinary tract obstruction: A systematic review and Bayesian meta-analysis.

BACKGROUND: Lower urinary tract obstruction (LUTO) is a rare but critical fetal diagnosis. Different ultrasound markers have been reported with varying sensitivity and specificity. AIMS: The objective of this systematic review and meta-analysis was to identify the diagnostic accuracy of ultrasound markers for LUTO. MATERIALS AND METHODS: We performed a systematic literature review of studies reporting on fetuses with hydronephrosis or a prenatally suspected and/or postnatally confirmed diagnosis of LUTO. Bayesian bivariate random effects meta-analytic models were fitted, and we calculated posterior means and 95% credible intervals for the pooled diagnostic odds ratio (DOR). RESULTS: A total of 36,189 studies were identified; 636 studies were available for full text review and a total of 42 studies were included in the Bayesian meta-analysis. Among the ultrasound signs assessed, megacystis (DOR 49.15, [15.28, 177.44]), bilateral hydroureteronephrosis (DOR 41.33, [13.36,164.83]), bladder thickening (DOR 13.73, [1.23, 115.20]), bilateral hydronephrosis (DOR 8.36 [3.17, 21.91]), male sex (DOR 8.08 [3.05, 22.82]), oligo- or anhydramnios (DOR 7.75 [4.23, 14.46]), and urinoma (DOR 7.47 [1.14, 33.18]) were found to be predictive of LUTO (Table 1). The predictive sensitivities and specificities however are low and wide study heterogeneity existed. DISCUSSION: Classically, LUTO is suspected in the presence of prenatally detected megacystis with a dilated posterior urethra (i.e., the keyhole sign), and bilateral hydroureteronephrosis. However, keyhole sign has been found to have modest diagnostic performance in predicting the presence of LUTO in the literature which we confirmed in our analysis. The surprisingly low specificity may be influenced by several factors, including the degree of obstruction, and the diligence of the sonographer at searching for and documenting it during the scan. As a result, providers should consider this when establishing the differential for a fetus with hydronephrosis as the presence or absence of keyhole sign does not reliably rule in or rule out LUTO. CONCLUSIONS: Megacystis, bilateral hydroureteronephrosis and bladder wall thickening are the most accurate predictors of LUTO. Given the significant consequences of a missed LUTO diagnosis, clinicians providing counselling for prenatal hydronephrosis should maintain a low threshold for considering LUTO as part of the differential diagnosis.

Vascular inflow after renal transplantation: Does the arteriotomy technique impact early allograft perfusion and function?

BACKGROUND: There are two main techniques for arterial reconstruction in RT: TA using a stab longitudinal incision which creates an elliptical opening and AP which fashions a circular defect. We hypothesized that AP creates a natural anastomosis lumen, similar to the donor renal artery, which optimizes RT perfusion. METHODS: A retrospective review of a single-institution database was performed between 2000 and 2018. Twenty patients who underwent AP arteriotomy were compared to 40 TA-matched controls. Data were collected on creatinine (preoperative, nadir, and time to nadir), and DUS RI and PSV at 1 week, 3 months, and 6-12 months post-RT. RESULTS: ttNC was shorter in the AP group (5 ± 4 vs 12 ± 13 days; P = .03). PSV at 1 week was lower in the AP group (186 ± 65 cm/s vs 232 ± 89 cm/s; P = .04). There was no difference in nadir creatinine value (P = .26), preoperative creatinine (P = .66), and initial postoperative creatinine (P = .80). RI at week 1 were not different between groups (P = .37). Follow-up DUS showed the difference in PSV between groups became non-significant (1 month P = .50 and 6-12 months P = .53). CONCLUSIONS: AP arteriotomy in RT improves early perfusion and function parameters (ttNC and initial PSV) as compared to TA. AP arteriotomy optimizes early allograft reperfusion, which may have important long-term implications and deserves further evaluation.

Perineural invasion on biopsy is associated with upstaging at radical prostatectomy in Gleason score 3 + 4 = 7 prostate cancer.

This study assesses if perineural invasion (PNI) detected on biopsy with Gleason score (GS) 3 + 4 = 7 prostate cancer (PCa) is associated with upstaging/upgrading of disease after radical prostatectomy (RP). 154 patients with GS 3 + 4 = 7 PCa diagnosed from biopsy who underwent RP were assessed for PNI. The percentage of biopsy sites with PNI (%PNI) was also calculated. Pattern 4 morphologies (ill-defined glands [IDG], fused, cribriform, and glomerulations) were also assessed. Clinical information, GS and stage after RP were retrieved from the medical records. 45 % (69/154) of patients were upstaged (≥pT3) and 29 % (44/154) were upgraded to GS >3 + 4 = 7 after RP. 37 % (57/154) of patients had PNI which was associated with upstaging (RR 1.4; P = 0.04) but not upgrading (RR 0.9; P = 0.7). There was higher %PNI in upstaged patients (12.1 % ± 1.8 vs. 7.1 % ± 1.5, P = 0.03) with a significant correlation between %PNI and ≥pT3 (r = 0.178, P = 0.027). After multivariate analysis, only cribriform formations were significantly associated with upstaging (P = 0.009). The presence of PNI in biopsies with GS 3 + 4 = 7 PCa is associated with upstaging at RP but is a weaker predictor of ≥pT3 disease than cribriform morphology.

Suture slippage in knotless suture anchors resulting in subacromial-subdeltoid bursitis.

Rotator cuff repair using a suture bridge and knotless suture anchors is a relatively new, but increasingly used technique. The suture bridge technique creates an anatomically similar and more secure rotator cuff repair compared with conventional arthroscopic techniques and the use of knotless anchors eliminates the challenges associated with knot tying during arthroscopic surgery. However, previous in vitro biomechanical tests have shown that the hold of the suture in a knotless suture anchor is far lower than the pullout strength of the anchor from bone. Up until now slippage has been a theoretical concern. We present a prospectively diagnosed case of in vivo suture loosening after rotator cuff repair using a knotless bridge technique resulting in subacromial-subdeltoid bursitis.

Pediatric testicular torsion management practices A survey of Canadian urologists.

INTRODUCTION: Pediatric testicular torsion (TT) is a urologic emergency that may result in testicular loss if left untreated. Testicular salvage is dependent on prompt intervention, and thus delays in diagnosis and management may threaten testicular viability. Knowledge of real-world Canadian practice patterns for pediatric TT will allow optimization of practices based on resource availability and geographic limitations to improve care. METHODS: An electronic survey on pediatric TT management was distributed to Canadian urologists. Descriptive statistics were performed on respondent demographic factors, hospital policies and barriers to care, surgical approaches, and transfer practices. Respondent practice patterns were analyzed based on geographic location and training. RESULTS: Thirty-four urologists responded, with most respondents operating a community practice. Ultrasonography (US) was frequently used to support TT diagnosis. Despite this, poor US access was often cited as a barrier to care, with particular impact on rural urologists. Neonatal patients and <10 years old were commonly transferred to a pediatric hospital for definitive management due to surgeon discomfort and hospital policies. Reported transport methods commonly included use of the patient's own vehicle or ambulance based on availability and timing. CONCLUSIONS: Neonatal patients and patients under 10 years old are most commonly reported to be transferred to pediatric hospitals for TT management. Patients located in rural locations and at centers with limited US access may be at risk for delayed diagnosis and treatment. Pathways for prompt management of suspected TT may better serve these younger pediatric patients.

Radiation exposure associated with computed tomography for pediatric urolithiasis evaluation: A scoping review of the literature.

INTRODUCTION: Computed tomography (CT) imaging is used for assessment of pediatric urolithiasis in cases where ultrasound is inconclusive. The utility of CT imaging must be considered alongside the potential risks of radiation exposure in this patient population due to the increased risk of cancer development. The purpose of this review is to investigate the radiation exposure associated with standard-dose and low-dose computed tomography (CT) imaging for the assessment of pediatric urolithiasis. METHODS: A scoping literature review over a 23 year period between 2000 and 2023 was conducted of all English-language studies reporting on the use of non-contrast CT imaging for assessment of pediatric urolithiasis. Patients that were specified as pediatric with age ≤20 years at time of intervention and undergoing standard-dose or low/ultra-low-dose CT were included. Low-dose and ultra-low-dose CT were defined as a radiation dose ≤3.0 mSv and ≤1.9 mSv, respectively. RESULTS: A total of 8121 articles were identified and after screening, 6 articles representing 309 patients were included in this scoping review. Of the articles reviewed, standard non-contrast CT radiation doses for pediatric urolithiasis evaluation ranged from 2.9 to 5.5 mSv and low-dose CT radiation dose was reported to be 1.0-2.72 mSv. Only 2 studies directly evaluated low-dose CT imaging compared to standard-dose CT imaging for pediatric urolithiasis assessment. Radiation reduction approaches did not negatively impact urolithiasis detection or characterization in 2 studies reviewed. CONCLUSIONS: CT radiation doses for suspected or known pediatric urolithiasis are underreported and vary greatly with underutilization of low-dose/ultra-dose protocols for pediatric urolithiasis especially in comparison to the adult population. Results from this scoping review support that low-dose CTprotocols for pediatric stone disease are feasible to reduce radiation exposure.

AI-PEDURO - Artificial intelligence in pediatric urology: Protocol for a living scoping review and online repository.

BACKGROUND: Artificial intelligence (AI) and machine learning (ML) methods are increasingly being applied in pediatric urology across a growing number of settings, with more extensive databases and wider interest for use in clinical practice. More than 30 ML models have been published in the pediatric urology literature, but many lack items required by contemporary reporting frameworks to be high quality. For example, most studies lack multi-institution validation, validation over time, and validation within the clinical environment, resulting in a large discrepancy between the number of models developed versus the number of models deployed in a clinical setting, a phenomenon known as the AI chasm. Furthermore, pediatric urology is a unique subspecialty of urology with low frequency conditions and complex phenotypes where clinical management can rely on a lower quality of evidence. OBJECTIVE: To establish the AI in PEDiatric UROlogy (AI-PEDURO) collaborative, which will carry out a living scoping review and create an online repository (www.aipeduro.com) for models in the field and facilitate an evidence synthesis of AI models in pediatric urology. METHODS AND ANALYSIS: The scoping review will follow PRISMA-ScR guidelines. We will include ML models identified through standardized search methods of four databases, hand-search papers, and user-submitted models. Retrieved records will be included if they involve ML algorithms for prediction, classification, or risk stratification for pediatric urology conditions. The results will be tabulated and assessed for trends within the literature. Based on data availability, models will be divided into clinical disease sections (e.g. hydronephrosis, hypospadias, vesicoureteral reflux). A risk assessment will be performed using the APPRAISE-AI tool. The retrieved model cards (brief summary model characteristics in table form) will be uploaded to the online repository for open access to clinicians, patients, and data scientists, and will be linked to the Digital Object Identifier (DOI) for each article. DISCUSSION AND CONCLUSION: We hope this living scoping review and online repository will offer a valuable reference for pediatric urologists to assess disease-specific ML models' scope, validity, and credibility to encourage opportunities for collaboration, external validation, clinical testing, and responsible deployment. In addition, the repository may aid in identifying areas in need of further research.

Diagnosis, Classification, and Contemporary Management of Undescended Testicles.

This article provides a comprehensive review regarding undescended testicles and other related conditions. We have included background information summarizing variable clinical presentations, epidemiology, and the implications of undescended testis (UDT) on fertility and malignancy risk. This article has an emphasis on the approach to diagnosis and surgical management for the UDT. The purpose of this review is to provide readers with useful clinical tools for assessing and treating patients with cryptorchidism.

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.