Expert Consensus on Pediatric Urodynamics Reporting Using Modified Delphi Technique.

PURPOSE: Urodynamic testing (UDS) is an important tool in the management of pediatric lower urinary tract conditions. There have been notable efforts to standardize pediatric UDS nomenclature and technique, but no formal guidelines exist on essential elements to include in a clinical report. We sought to identify ideal structure and elements of a pediatric UDS assessment based on expert consensus. MATERIALS AND METHODS: Pediatric urologists regularly performing UDS were queried using a Delphi process. Participants were invited representing varied geographic, experience, and societal involvement. Participants underwent 3 rounds of questionnaires between November 2022 and August 2023 focusing on report organization, elements, definitions, and automated electronic health record clinical decision support. Professional billing requirements were also considered. Consensus was defined as 80% agreeing either in favor of or against a topic. Elements without consensus were discussed in subsequent rounds. RESULTS: A diverse sample of 30 providers, representing 27 institutions across 21 US states; Washington, District of Columbia; and Canada completed the study. Participants reported interpreting an average number of 5 UDS reports per week (range 1-22). The finalized consensus report identifies 93 elements that should be included in a pediatric UDS report based on applicable study conditions and findings. CONCLUSIONS: This consensus report details the key elements and structure agreed upon by an expert panel of pediatric urologists. Further standardization of documentation should aid collaboration and research for patients undergoing UDS. Based on this information, development of a standardized UDS report template using electronic health record implementation principles is underway, which will be openly available for pediatric urologists.

Effect of Return Electrode Placement at Apical Cochleostomy on Current Flow With a Cochlear Implant.

OBJECTIVES: A method for stimulating the cochlear apex using perimodiolar electrode arrays is described. This method involves implanting an electrode (ECE1) into the helioctrema in addition to standard cochlear implant placement. One objective is to verify a suitable approach for implanting ECE1 in the helicotrema. Another is to determine how placement of ECE1 reshapes electric fields. DESIGN: Two cadaveric half-heads were implanted, and electric voltage tomography was measured with ECE1 placed in many positions. RESULTS: An approach for placing ECE1 was identified. Changes in electric fields were only observed when ECE1 was placed into the fluid in the helicotrema. When inside the helicotrema, electric voltage tomography modeling suggests an increased current flow toward the apex. CONCLUSIONS: Placement of ECE1 into the cochlear apex is clinically feasible and has the potential to reshape electric fields to stimulate regions of the cochlea more apical than those represented by the electrode array.

Deep Learning of Videourodynamics to Classify Bladder Dysfunction Severity in Patients With Spina Bifida.

PURPOSE: Urologists rely heavily on videourodynamics to identify patients with neurogenic bladders who are at risk of upper tract injury, but their interpretation has high interobserver variability. Our objective was to develop deep learning models of videourodynamics studies to categorize severity of bladder dysfunction. MATERIALS AND METHODS: We performed a cross-sectional study of patients aged 2 months to 28 years with spina bifida who underwent videourodynamics at a single institution between 2019 and 2021. The outcome was degree of bladder dysfunction, defined as none/mild, moderate, and severe, defined by a panel of 5 expert reviewers. Reviewers considered factors that increase the risk of upper tract injury, such as poor compliance, elevated detrusor leak point pressure, and detrusor sphincter dyssynergia, in determining bladder dysfunction severity. We built 4 models to predict severity of bladder dysfunction: (1) a random forest clinical model using prospectively collected clinical data from videourodynamics studies, (2) a deep learning convolutional neural network of raw data from the volume-pressure recordings, (3) a deep learning imaging model of fluoroscopic images, (4) an ensemble model averaging the risk probabilities of the volume-pressure and fluoroscopic models. RESULTS: Among 306 videourodynamics studies, the accuracy and weighted kappa of the ensemble model classification of bladder dysfunction when at least 75% expected bladder capacity was reached were 70% (95% CI 66%,76%) and 0.54 (moderate agreement), respectively. The performance of the clinical model built from data extracted by pediatric urologists was the poorest with an accuracy of 61% (55%, 66%) and a weighted kappa of 0.37. CONCLUSIONS: Our models built from urodynamic pressure-volume tracings and fluoroscopic images were able to automatically classify bladder dysfunction with moderately high accuracy.

Deep learning imaging features derived from kidney ultrasounds predict chronic kidney disease progression in children with posterior urethral valves.

BACKGROUND: We sought to use deep learning to extract anatomic features from postnatal kidney ultrasounds and evaluate their performance in predicting the risk and timing of chronic kidney disease (CKD) progression for boys with posterior urethral valves (PUV). We hypothesized that these features would predict CKD progression better than clinical characteristics such as nadir creatinine alone. METHODS: We performed a retrospective cohort study of boys with PUV treated at two pediatric health systems from 1990 to 2021. Features of kidneys were extracted from initial postnatal kidney ultrasound images using a deep learning model. Three time-to-event prediction models were built using random survival forests. The Imaging Model included deep learning imaging features, the Clinical Model included clinical data, and the Ensemble Model combined imaging features and clinical data. Separate models were built to include time-dependent clinical data that were available at 6 months, 1 year, 3 years, and 5 years. RESULTS: Two-hundred and twenty-five patients were included in the analysis. All models performed well with C-indices of 0.7 or greater. The Clinical Model outperformed the Imaging Model at all time points with nadir creatinine driving the performance of the Clinical Model. Combining the 6-month Imaging Model (C-index 0.7; 95% confidence interval [CI] 0.6, 0.79) with the 6-month Clinical Model (C-index 0.79; 95% CI 0.71, 0.86) resulted in a 6-month Ensemble Model that performed better (C-index 0.82; 95% CI 0.77, 0.88) than either model alone. CONCLUSIONS: Deep learning imaging features extracted from initial postnatal kidney ultrasounds may improve early prediction of CKD progression among children with PUV. A higher resolution version of the Graphical abstract is available as Supplementary information.

Quantifying Glans Width Changes in Response to Preoperative Androgen Stimulation in Patients Undergoing Hypospadias Repair.

PURPOSE: Testosterone (T) administration prior to hypospadias surgery to increase glans size remains controversial. Understanding T's effect on glans width (GW) is essential to understanding its potential impact on surgical outcomes. We hypothesized that preoperative T in prepubertal boys significantly increases GW at the time of hypospadias surgery. MATERIALS AND METHODS: Our single institutional database was queried to identify patients who underwent hypospadias surgery from 2016 to 2020, in which data for T administration and GW were available. Descriptive, nonparametric and categorical statistics were performed as indicated. RESULTS: A total of 579 patients were eligible for analysis. Median age at surgery was 0.9 years (IQR 0.6-1.6). A total of 247/579 patients (42.7%) received T. The median GW at surgery was 15 mm (IQR 13-17). When comparing patients who had T administered to those who did not, we found a significant difference in GW at surgery (16 mm vs 14 mm, p <0.001). The median change in GW from the office to surgery was 4 mm for those receiving T vs 0 mm for those not receiving T (p <0.001). We identified a greater change in GW from preoperative to intraoperative measurements in patients who received 2 doses of T vs 1 dose (4 mm vs 2 mm, p <0.001). A histogram plot revealed the distribution of GW change at surgery. CONCLUSIONS: In our prospectively collected cohort of patients undergoing hypospadias surgery, we were able to quantitate the change in GW from preoperative T. Two doses of T resulted in a significant increase in GW vs 1 dose.

Expanding the Use of Nephron-Sparing Surgery for Wilms Tumor.

Radical nephrectomy combined with contemporary chemotherapeutic and radiation therapy protocols has drastically improved outcomes for children with Wilms tumor. Patients with bilateral disease and a syndrome predisposing to tumor development have necessitated the use of nephron-sparing surgery in select cases. Success in managing these patients has increased the indication for partial nephrectomy, although current guidelines for unilateral Wilms tumor are limited. Given that children are being cured with increasing success, recent focus has shifted to long-term health outcomes in addition to tumor treatment. Specifically, renal function has an impact on long-term cardiovascular health and events. Adult outcomes with partial nephrectomy provide a guideline for a paradigm shift in the management of children with Wilms tumor, particularly with advances in imaging and adjuvant therapy. The data are limited for children undergoing partial nephrectomy for unilateral Wilms tumor and outcomes for larger tumors will need to be studied closely in future trials. Increased utilization of neoadjuvant chemotherapy could further expand the number of patients eligible for partial nephrectomy.

Total Motile Sperm Count in Adolescent Boys with Varicocele is Associated with Hormone Levels and Total Testicular Volume.

PURPOSE: The risk factors for future infertility in adolescents with varicocele are controversial, and little is known about the association between hormone levels and semen parameters. Semen analysis is likely the closest marker of fertility but may be difficult to obtain in some boys secondary to personal, familial or religious reasons. Identifying other clinical surrogates for abnormal semen parameters may offer an alternative for assessing varicocele severity in these boys. We hypothesized that hormone levels and total testicular volume are predictive of abnormal total motile sperm count. MATERIALS AND METHODS: We retrospectively reviewed Tanner 5 boys with palpable left varicoceles who underwent a semen analysis and had serum hormone levels tested (luteinizing hormone, follicle-stimulating hormone, inhibin B, anti-müllerian hormone and/or total testosterone) within a 6-month period. Total testicular volume was also calculated. Abnormal total motile sperm count was defined as <9 million sperm per ejaculate. RESULTS: A total of 78 boys (median age 17.2 years, IQR 16.5-18.0) were included. Luteinizing hormone, anti-müllerian hormone and total testosterone were not correlated with any semen analysis parameter. There was a negative correlation between follicle-stimulating hormone and total motile sperm count (ρ -0.35, p=0.004) and positive correlation between inhibin B and total motile sperm count (ρ 0.50, p <0.001). Total testicular volume was significantly positively correlated with total motile sperm count (ρ 0.35, p=0.01). ROC analyses revealed an optimal follicle-stimulating hormone cutoff of 2.9, an optimal inhibin B cutoff of 204 and an optimal total testicular volume cutoff of 34.4 cc to predict abnormal total motile sperm count. CONCLUSIONS: Total motile sperm count is inversely associated with follicle-stimulating hormone levels, and directly associated with inhibin B levels and total testicular volume. Optimized cutoffs for serum follicle-stimulating hormone, inhibin B and total testicular volume may prove to be reasonable surrogates for total motile sperm count in boys who defer semen analysis for personal or religious/cultural reasons.

Time to Complication Detection after Primary Pediatric Hypospadias Repair: A Large, Single Center, Retrospective Cohort Analysis.

PURPOSE: Controversy remains within the pediatric urology community regarding adequate duration of followup after hypospadias repair. Some have suggested that minimal long-term followup is necessary due to a low incidence of late complications. The objective of this study was to delineate time to complication detection for primary hypospadias repairs. MATERIALS AND METHODS: We queried our prospectively maintained hypospadias database and identified all patients undergoing primary hypospadias repair from June 2007 to June 2018. Patients were excluded if they had undergone primary repair elsewhere or did not have a followup visit. Complications were defined by the need for an additional unplanned surgical procedure. Kaplan-Meier analysis was performed to assess time to complication by degree of hypospadias. RESULTS: A total of 1,280 patients met inclusion criteria, of whom 976 (68.9%) underwent distal, 64 (4.9%) mid shaft and 240 (18.8%) proximal hypospadias repair. Complication rates were 10.7% (104 patients), 18.8% (12) and 53.8% (129, p<0.0001) for distal, mid shaft and proximal hypospadias repair, respectively. Only 47% of complications were detected within the first year postoperatively. Median time to complication for all repair types was 69.2 months (IQR 23 to 131.9), ie 83.1 months (IQR 42.0 to 131) for patients undergoing distal repair and 29.4 months (IQR 11.9 to 82.1) for patients undergoing proximal repair (p <0.001). CONCLUSIONS: In our large single institution series of pediatric patients undergoing hypospadias repair fewer than half of the complications presented within the first year postoperatively. Long-term followup is recommended for patients undergoing hypospadias repair to adequately detect and address complications.

A multiplexed in vitro assay system for evaluating human skeletal muscle functionality in response to drug treatment.

In vitro systems that mimic organ functionality have become increasingly important tools in drug development studies. Systems that measure the functional properties of skeletal muscle are beneficial to compound screening studies and also for integration into multiorgan devices. To date, no studies have investigated human skeletal muscle responses to drug treatments at the single myotube level in vitro. This report details a microscale cantilever chip-based assay system for culturing individual human myotubes. The cantilevers, along with a laser and photo-detector system, enable measurement of myotube contractions in response to broad-field electrical stimulation. This system was used to obtain baseline functional parameters for untreated human myotubes, including peak contractile force and time-to-fatigue data. The cultured myotubes were then treated with known myotoxic compounds and the resulting functional changes were compared to baseline measurements as well as known physiological responses in vivo. The collected data demonstrate the system's capacity for screening direct effects of compound action on individual human skeletal myotubes in a reliable, reproducible, and noninvasive manner. Furthermore, it has the potential to be utilized for high-content screening, disease modeling, and exercise studies of human skeletal muscle performance utilizing iPSCs derived from specific patient populations such as the muscular dystrophies.

Long-Term Electrical and Mechanical Function Monitoring of a Human-on-a-Chip System.

The goal of human-on-a-chip systems is to capture multi-organ complexity and predict the human response to compounds within physiologically relevant platforms. The generation and characterization of such systems is currently a focal point of research given the long-standing inadequacies of conventional techniques for predicting human outcome. Functional systems can measure and quantify key cellular mechanisms that correlate with the physiological status of a tissue, and can be used to evaluate therapeutic challenges utilizing many of the same endpoints used in animal experiments or clinical trials. Culturing multiple organ compartments in a platform creates a more physiologic environment (organ-organ communication). Here is reported a human 4-organ system composed of heart, liver, skeletal muscle and nervous system modules that maintains cellular viability and function over 28 days in serum-free conditions using a pumpless system. The integration of non-invasive electrical evaluation of neurons and cardiac cells and mechanical determination of cardiac and skeletal muscle contraction allows the monitoring of cellular function especially for chronic toxicity studies in vitro. The 28 day period is the minimum timeframe for animal studies to evaluate repeat dose toxicity. This technology could be a relevant alternative to animal testing by monitoring multi-organ function upon long term chemical exposure.

Predicting and Modifying Risk for Development of Renal Failure in Boys with Posterior Urethral Valves.

PURPOSE OF REVIEW: The purpose of this review is to bring the reader up to date on the current risk factors for the development of renal deterioration in the boys with posterior urethral valves (PUV) and approaches to modify this risk. RECENT FINDINGS: Renal bladder ultrasound (RBUS) is routinely performed in boys with PUV and recent advancements allow imaging processing that can more accurately quantify renal parenchyma and correlate this with risk for renal loss. Refinement of urine studies may improve our ability to stratify patients into renal loss categories. Use of videourodynamics (VUDS) allows refined assessment of the valve bladder to identify those who might benefit from secondary procedures and/or the addition of targeted pharmacotherapy to improve bladder emptying or dangerous storage pressures. All boys with a history of PUV are at a significant long-term risk of renal deterioration. The literature suggests that several technical advances have improved our ability to predict this risk, although there needs to be further refinement and validation before widespread use. Utilization of close follow-up, VUDS, pharmacotherapy, and bladder drainage provide the best methods to improve care to this group of patients and if more studies confirm their utility, adoption of these as part of standard of care protocols may be warranted.

Intermediate-Term Followup of Proximal Hypospadias Repair Reveals High Complication Rate.

PURPOSE: Results following distal hypospadias repair are favorable. Grouping proximal and distal hypospadias repair artificially increases the perceived success rate of proximal hypospadias. We identified our complication rate of proximal hypospadias repair and hypothesized a higher complication rate for 1-stage repair. MATERIALS AND METHODS: We retrospectively reviewed the records of consecutive boys who underwent proximal hypospadias from 2007 to 2014. Proximal hypospadias was defined as a urethral meatus location at or more proximal than the penoscrotal junction after penile degloving. We further stratified boys into those with planned 1-stage vs 2-stage repair. Univariate and Cox regression analyses were performed to assess associations with covariates and compare time to the first complication, respectively. RESULTS: A total of 167 boys met study inclusion criteria. Median followup was 31.7 months for 1-stage repair in 86 patients and staged repair in 81. The overall complication rate was 56%. Complications developed in 53 of 86 1-stage (62%) vs 40 of 81 staged (49%) repairs (p = 0.11). The number of unplanned procedures per patient was higher in the 1-stage than in the staged group (0.99 vs 0.69, p = 0.06), as was the number of patients who had at least 2 complications (29 of 86 or 33% vs 13 of 81 or 16%, p = 0.03). Cox regression showed no difference in time to the first complication for staged compared to 1-stage repair (HR 0.77, 95% CI 0.43-1.39). CONCLUSIONS: Our 56% complication rate of proximal hypospadias warrants further long-term patient followup. More patients in the 1-stage group experienced at least 2 complications. However, when complications developed, they developed no differently in the 2 groups.

Child Abuse Mimic: Avulsion Injury in a Child With Penoscrotal Webbing.

Sexual abuse of children is prevalent in today's society. In 2012, approximately 686,000 children (9.2 per 1000) in the United States were determined to be victims of substantiated child abuse and neglect, according to national data compiled by child protective service agencies; victimization rates were highest for children younger than 1 year. Nearly 9.3% of maltreated children were victims of sexual abuse, this finding was reported by US Department of Health and Human Services (http://www.acf.hhs.gov/programs/cb/research-data-technology/statistics-research/child-maltreatment). Previous research has shown that as many as 1 in 3 girls and 1 in 7 boys will be sexually abused during childhood (Child Abuse Negl. 2003;27:1205-1222). Although sexual abuse seems to be less common in boys than girls, this may be partly due to underdiagnosis and underreporting of sexual abuse in boys (Arch Dis Child. 2007;92:328-331). Clinicians should therefore consider the possibility of sexual abuse when boys present with genital injuries, because failing to recognize and diagnose sexual abuse can pose an ongoing safety risk to a child. However, an erroneous diagnosis of sexual abuse can have equally hazardous repercussions, including removal of a child from their caregivers or prosecution of an innocent individual. A number of medical conditions can mimic child sexual abuse injuries, including anal fissures, failure of midline fusion, perianal streptococcal dermatitis, and straddle injury (J Pediatr Health Care. 2009;23:283-288 and Acta Paediatr. 2011;100:590-593). The following case involves a 5-week-old male infant who presented to the pediatric emergency department with an avulsion injury to his penis concerning for sexual abuse. He was ultimately diagnosed with a relatively rare anatomic variant of the genitalia and determined to have sustained an accidental injury whose appearance mimicked abuse.

Connectivity-based functional analysis of dopamine release in the striatum using diffusion-weighted MRI and positron emission tomography.

The striatum acts in conjunction with the cortex to control and execute functions that are impaired by abnormal dopamine neurotransmission in disorders such as Parkinson's and schizophrenia. To date, in vivo quantification of striatal dopamine has been restricted to structure-based striatal subdivisions. Here, we present a multimodal imaging approach that quantifies the endogenous dopamine release following the administration of d-amphetamine in the functional subdivisions of the striatum of healthy humans with [(11)C]PHNO and [(11)C]Raclopride positron emission tomography ligands. Using connectivity-based (CB) parcellation, we subdivided the striatum into functional subregions based on striato-cortical anatomical connectivity information derived from diffusion magnetic resonance imaging (MRI) and probabilistic tractography. Our parcellation showed that the functional organization of the striatum was spatially coherent across individuals, congruent with primate data and previous diffusion MRI studies, with distinctive and overlapping networks. d-amphetamine induced the highest dopamine release in the limbic followed by the sensory, motor, and executive areas. The data suggest that the relative regional proportions of D2-like receptors are unlikely to be responsible for this regional dopamine release pattern. Notably, the homogeneity of dopamine release was significantly higher within the CB functional subdivisions in comparison with the structural subdivisions. These results support an association between local levels of dopamine release and cortical connectivity fingerprints.