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Congenital abnormalities of the kidneys and urinary tract (CAKUT) encompass a spectrum of pathology ranging in severity from incidental findings to marked deviations of anatomic form and function. The imaging appearance of CAKUT generally reflects a deviation from normal embryologic development. Common and uncommon congenital abnormalities of the kidneys, ureters, bladder, and urethra are reviewed with an emphasis on the imaging appearance and embryologic origin so that they may be promptly identified and treated when encountered in clinical practice., Competing Interests: Disclosure None., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Contrast media are an indispensable adjunct to pediatric imaging. The most common include iodine-based contrast media for CT and fluoroscopy, gadolinium-based contrast media and iron-oxide nanoparticles for MRI, and microbubbles for ultrasound. Although many of the considerations in the routine use of contrast media in infants and children (relating for example to renal function, allergic-like reactions, GBCM deposition, and extravasations) are similar to considerations in adult patients, some important differences exist. These variances are often age-dependent and require an appreciation of pediatric physiology for safe and effective clinical practice. This article highlights ten concepts relating to contrast media administration for diagnostic imaging in children that are important for radiologists and pediatricians to recognize and understand. We present contrast media classes and their use in children, discuss safety concerns and complications, and explore environmental impacts.

Background: Technique survival, also reported with negative connotations as technique failure or transfer from peritoneal dialysis to haemodialysis, has been identified by patients, caregivers and health professionals as a critically important outcome to be reported in all trials. However, there is wide variation in how peritoneal dialysis technique survival is defined, measured and reported, leading to difficulty in comparing or consolidating results., Methods: We conducted an online international consensus workshop to establish a core outcome measure of technique survival. Discussions were analysed thematically., Results: Fifty-five participants including 14 patients and caregivers from 13 countries took part in facilitated breakout discussions using video-conferencing. The following themes were identified: capturing important aspects of the outcome (requiring a core event to define the outcome, distinguishing temporary from permanent events, recognising heterogeneous experiences of transfers), adopting appropriate neutral nomenclature (conveying with clarity, avoiding negative connotations), and ensuring feasibility and applicability (capturing data relevant to clinical and research settings, ease of adoption). The suggested definitions for the core outcome measure were 'the event of a transfer to haemodialysis', or 'discontinuation of peritoneal dialysis'. Applying the principles described within the workshop, defining the outcome measure as a 'transfer to haemodialysis' was preferable., Conclusions: It is proposed that the core outcome of technique survival is redefined as 'transfer to haemodialysis' and that its components are standardised using simple, neutral terminology Components considered important by stakeholders included recording the reasons for transfer from peritoneal dialysis, and focussing on permanent events whilst ensuring the outcome remains easy to implement., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship and/or publication of this article: ML and SD have received speaker's honoraria from Baxter Healthcare and Fresenius Medical Care, and an unrestricted research grant from Baxter Healthcare. JSFC has received speaker's honoraria and research funds from Baxter Healthcare, Fresenius Medical Care, Roche Pharmaceuticals and Amgen. NB has received speaking honoraria from Baxter Healthcare and Otsuka and is on the Advisory Board for Astra Zeneca, Fresenius Medical Care, Vifor, and GSK. DWJ has received consultancy fees, research grants, speaker's honoraria and travel sponsorships from Baxter Healthcare and Fresenius Medical Care, consultancy fees from Astra Zeneca, Bayer, and AWAK, speaker's honoraria from ONO and Boehringer Ingelheim & Lilly, and travel sponsorships from Ono and Amgen. He is a current recipient of an Australian National Health and Medical Research Council (NHMRC) Leadership Investigator Grant. AL has served as a consultant and member of advisory boards for Alnylam Pharmaceuticals, AstraZeneca, Baxter Healthcare, Bayer AG, Boehringer-Ingelheim, Chinook Therapeutics, Dimerix Limited, Eledon Pharmaceuticals, George Clinical, GlaxoSmithKline, Kira Pharmaceuticals, Prokidney, Otsuka Pharmaceuticals and Visterra Inc, Zai Lab Co. Ltd; has received Speaker's honorarium from AstraZeneca, Baxter Healthcare, Boehringer-Ingelheim, Chinook Therapeutics and Otsuka Pharmaceuticals; and has served as a member of Data Safety and Monitoring Committee for Dimerix Limited and Zai Lab Co. Ltd. AKJ has received research and education grants from Baxter Healthcare, Otsuka Pharmaceuticals and serves as an advisory board member for AWAK Technologies. JIS has served as a consultant and member of advisory boards for Healthmap Solutions and Dialco Medical, grants from the Canadian Institutes of Health Research, and speaker's honorarium from Outset Medical. AKV receives grant support from a Queensland Advancing Clinical Research Fellowship and an NHMRC Emerging Leader Grant. MW has received speakers honoraria from Baxter Healthcare and Fresenius Medical Care, consulting fees from Triomed AB, and an unrestricted research grant from Baxter Healthcare. RQ is the co-inventor of the Dialysis Information Management System™, Canada, and is the co-owner of the intellectual property associated with it, and has received honoraria and attended advisory boards for Baxter Healthcare. YC is a current recipient of the Australian NHMRC Emerging Leadership Investigator Grant (2022–2026) and Queensland Advancing Clinical Fellowship (2022–2025; mid-career). She has received honoraria and research grants from Baxter Healthcare and Fresenius Medical Care, and a consultancy fee from Bupa Health Insurance. ACNF has received honoraria for presentations from Baxter Healthcare and a Scholarship from Fond de Recherche du Québec – Santé. NA is supported by an NHMRC Postgraduate Scholarship. SQ is on the board of the Renal Physician's Association (unpaid) and a medical director at the Davita home dialysis unit. PG, KEM, TH, both AJ's, AMG, DP, AYW, JCC and EE have no disclosures.

Introduction: Zinner Syndrome (ZS), a rare congenital malformation of the mesonephric duct, combines seminal vesicle cyst (SVC) with ipsilateral upper urinary tract abnormalities. Typically asymptomatic in childhood, ZS manifests between 2nd to 4th decades with bladder symptoms, perineal pain and infertility. Diagnostic confirmation with additional imaging is needed when either renal or seminal abnormalities are identified., Materials and Methods: A retrospective study spanning 22 years identified 20 pediatric ZS cases through clinical analytics. Demographic, clinical, and radiological data were analyzed, including presenting complaints, imaging modalities (ultrasound, CT, MRI), and surgical findings. The study was HIPAA-compliant and IRB-approved., Results: Among 20 cases (mean age: 7.3 years), clinical presentations included asymptomatic cases, urinary symptoms, and abdominal pain. Imaging revealed renal anomalies (agenesis, multicystic dysplastic kidney) and seminal vesicle abnormalities. Surgical interventions (n = 12) addressed symptomatic cases, often involving robotic or laparoscopic procedures., Discussion: ZS, though rare, presents with varied clinical features, necessitating a multidisciplinary approach. Early diagnosis is facilitated by prenatal identification of renal abnormalities. Surgical intervention is reserved for symptomatic cases, with techniques such as vesiculectomy and resection of remnant structures employed., Conclusion: This study highlights ZS's diverse clinical and radiological spectrum, emphasizing the need for vigilance in detecting overlapping entities. Timely identification, utilizing advanced imaging techniques, is crucial for accurate diagnosis and appropriate management of Zinner Syndrome in the pediatric population., Competing Interests: Conflict of interest None., (Copyright © 2024 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

This publication provides an overview of current imaging indications and practices for patients undergoing gender-affirming surgery, with an emphasis on the importance of tailored, patient-specific care. Gender-affirming surgeries are performed with personalized approaches at various stages of life for those with intersex traits or differences in sex development (I/DSD) and transgender and gender diverse (TGD) individuals. For I/DSD patients, ultrasound, genitography, or MRI occurs during infancy and puberty to evaluate genital and gonadal anatomy. Facial harmonization involves bony and soft tissue modifications, guided by maxillofacial computerized tomography (CT) with three-dimensional reconstruction. Ultrasound is the main modality in assessing hormone-related and post-surgical changes in the chest. Imaging for genital reconstruction uses cross-sectional images and fluoroscopy to assess neoanatomy and complications., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Vesicoureteral reflux (VUR) is a common congenital anomaly of the urinary tract that can present with collecting system dilation or as a febrile infection. VUR can lead to permanent renal sequelae requiring surgery but can also spontaneously resolve without complication. Therefore, recognizing patient populations who warrant imaging for screening, confirmation, or ongoing surveillance for VUR is important, as is avoiding overdiagnosis. In the appropriate patient populations, an accurate diagnosis of VUR allows early treatment and prevention of pyelonephritis and scarring. Various imaging modalities are available to diagnose and grade VUR, including voiding cystourethrography, radionucleotide cystography, and contrast-enhanced voiding urosonography (ceVUS). The objective of this article is to summarize the current understanding of VUR diagnosis and management and to discuss these imaging modalities' strengths and pitfalls. Considerations include indications for VUR imaging, patient preparation, conduct of the examination, issues related to radiologic reporting, and cost-effectiveness. An emphasis is placed on ceVUS, which is the most recently introduced of the three imaging modalities and is receiving growing support among pediatric radiologists.

Background Fluoroscopy is an imaging modality associated with a wide range of dose levels, characterized using a variety of dose metrics, including effective dose. However, for clinical procedures, effective dose is a seldom-used and unregulated metric in the United States, and thus, it is not extensively studied in radiology despite potentially large clinical implications for patients, especially children and infants. Purpose To formulate and report a dose catalog across all diagnostic and interventional radiology (IR) fluoroscopy examination or procedure types at a specialized tertiary care pediatric hospital. Materials and Methods In this retrospective study, dose metrics taken from radiation dose structured reports of fluoroscopy between October 2014 and March 2023 were analyzed. The reports included fluoroscopy across 18 diagnostic examination types and 24 IR procedure types. The National Cancer Institute dosimetry system for Radiography and Fluoroscopy Monte Carlo software was used to estimate age-specific effective dose from dose-area product (DAP). The DAP-to-effective dose conversion factors were estimated per IR procedure type and diagnostic fluoroscopy examination type based on age. Results A total of 11 536 individual diagnostic fluoroscopy examinations (18 types) and 8017 individual IR procedures (24 types) were analyzed. Median effective dose values per diagnostic fluoroscopy examination type ranged from 0.0010 to 0.44 mSv (mean, 0.0808 mSv ± 0.0998 [SD]). Calculated DAP-to-effective dose conversion factors ranged from 0.04 to 2.48 mSv/Gy · cm 2 (mean, 0.758 mSv/Gy · cm 2 ± 0.614) across all diagnostic fluoroscopy examination types. Median effective dose values per IR procedure type ranged from 0.0007 to 3.90 mSv (mean, 0.6757 mSv ± 0.8989). Calculated DAP-to-effective dose conversion factors ranged from 0.001 to 0.87 mSv/Gy · cm 2 (mean, 0.210 mSv/Gy · cm 2 ± 0.235) across all IR procedure types. Conclusion A pediatric fluoroscopy dose catalog was created, including age-specific effective dose, using a repeatable robust method based on accurate clinical data. © RSNA, 2024 Supplemental material is available for this article . See also the editorial by Borrego and Balter in this issue.

Introduction: Somatosensory evoked potential (SSEP) and urodynamic studies (UD) are valuable tools for assessing patients with closed spinal dysraphism (CSD) before neurosurgical intervention. No studies have correlated their findings in this cohort and our aim is to study their correlation and prognostic value in pediatric patients with closed spinal dysraphism., Methods: Retrospective review of all patients referred to a multidisciplinary clinic in a tertiary pediatric surgical center over a 17 years period between April 2004 to September 2021 was performed. Inclusion criteria were <18 years old, diagnosed with CSD, with SSEP and UD done within 1 year of each other. Demographics data collected include age at presentation/at referral/at neurosurgical operation, gender, symptoms at presentation and intra-operative diagnoses. Pre-operative SSEP and UD findings were documented. Primary outcome was UD results in the group with normal and abnormal SSEP. Secondary outcome was urological and bowel function outcome in 4 groups of patients (Group A-both normal SSEP and UD, Group B- abnormal SSEP only, Group C - abnormal UD only and Group D-both abnormal SSEP and UD)., Results: A total of 45 patients were included for analysis. Mean follow up time was 118.9 months (24-216 months, SD 55.8 months). SSEP was normal in 20 patients and abnormal in 25 patients. Baseline demographics, preoperative symptoms and imaging were similar between 2 groups. Primary outcome Patients with abnormal SSEP were more likely to have abnormal UD results with a statistically significant difference (84% vs 40%, p < 0.05). They have a significantly higher end-fill detrusor pressure (12% vs 0%, p < 0.05), abnormal bladder compliance (20% vs 0%, p < 0.05), abnormal cystometric capacity (48% vs 10%, p < 0.05), poor emptying efficiency (24% vs 5%, p < 0.05) and sphincter incompetence (8% vs 0%, p < 0.05). Secondary outcome When compared to Groups A to C, patients in group D were more likely to be on anti-cholinergic (33.3% vs 4.3%, p < 0.05), required clean intermittent catheterization (42.9% vs 4.3%, p < 0.05) and had intravesical botulinum injection (19% vs 0%, p < 0.05). All the patients who had augmentation cystoplasty were in this group as well. Bowel function in terms of regular enema use was also statistically significantly higher in this group (33.4% p < 0.05)., Conclusion: Pre-operative SSEP and UD results correlate well in patients with closed spinal dysraphism. Patients with abnormal SSEP and UD preoperatively have higher risk of urological deterioration over time. Close monitoring in this group is warranted., (Copyright © 2022 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: There is limited quality of evidence regarding the accuracy of contrast-enhanced voiding urosonography (ceVUS) for diagnosis of vesicoureteral reflux (VUR) compared to fluoroscopic voiding cystourethrography (VCUG), and minimal data on the use of the ultrasound contrast agent Optison™ for this purpose., Objective: To compare the accuracy of ceVUS using Optison™ to VCUG, and to assess inter-rater agreement regarding presence and grading of VUR., Study Design: In this retrospective investigation, all sequential ceVUS with Optison™ and VCUG studies performed in children between 2014 and 2017 were reviewed. Two raters independently graded all ceVUS studies using a 5-point scale. CeVUS sensitivity and specificity were estimated separately for each rater using the VCUG report as the ground truth for presence and degree of VUR. Logistic and ordinary linear regression models assessed rater-report agreement and inter-rater agreement for each kidney, Optison™ dose, and referral diagnosis., Results: 97 children (51 females) with 101 paired studies were included. Sensitivity and specificity of ceVUS for VUR detection were identical for both raters: right kidney 75%/90.9%; left kidney 85.7%/78.9% (Figure). There was no statistically significant difference in disagreement between raters and the VCUG report for the right or left kidney. Inter-rater agreement on ceVUS grading was 90% and 88% for right and left kidneys, respectively. There was a significant negative association between fetal hydronephrosis vs urinary tract infection and disagreement between Rater 2 and the VCUG report for the left kidney. There were no other significant associations with respect to either kidney, Optison™ dose, or referral diagnosis., Discussion: Our study showed that detection of VUR with ceVUS and Optison™ is comparable to fluoroscopic VCUG. Based on the VCUG reports, the incidence of VUR in our patient population was substantially lower than in the meta-analysis of Chua et al. and in the study of Kim et al. The explanation for the large discrepancy in VUR incidence may reflect differences in the patient populations, and in our reporting of VUR with respect to kidney number rather than to pelviureteral units. Study limitations include its retrospective nature and potential bias in terms of patient selection. Since VUR is an intermittent phenomenon, sequential rather than simultaneous performance of the ceVUS and fluoroscopic studies might have influenced VUR detection., Conclusion: A blinded comparison of ceVUS performed with Optison™ to fluoroscopic VCUG showed moderate-good sensitivity and specificity for diagnosis of VUR., (Copyright © 2022 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: Assessment of the ureter is a fundamental part of the radiologic evaluation of the urinary tract. Abnormal ureteral dilation warrants further investigation to assess the etiology, which includes obstruction and/or reflux. Despite this fundamental need, there are no established normative values in children based on imaging., Objective: To provide normative values for ureteral diameter in pediatric patients with age-related ranges., Materials and Methods: We retrospectively reviewed all magnetic resonance (MR) urography studies and chose only normal ureters for assessment. The images were analyzed on commercially available software to assess maximum internal diameter. Manual measurements were done in cases where the images were below the resolution for automated assessment. Maximum intraluminal ureteral diameters were measured in upper, mid and lower thirds and the average of the three maximum ureteral diameters was used to obtain the average widest internal ureteral diameter. Multivariable linear regression was performed to test the association between the calculated diameter and gender. Differences in sizes between the left and right ureter were assessed using paired Wilcoxon signed rank test., Results: One hundred twenty-one MR urography studies were selected, which included 160 ureter units. The diameter increases progressively with age, ranging from 3.2 mm during infancy to 5.0 mm in patients older than 16 years of age. After 9 years of age, the average widest internal ureteral diameter is slightly larger in males compared to females (odds ratio [OR]=1.91, 95% confidence interval [CI] [1.63, 2.25], P<0.0001). The right ureter was slightly larger than the left (3.9 mm vs. 3.7 mm, P=0.004) among 39 patients in whom both right and left ureter units were included. The average mid ureteral diameter is widest, followed by the distal third then proximal third., Conclusion: We present the normative values for the average widest internal ureteral diameter based on laterality and different segments. In the pediatric population, 3.8 mm should be considered the average widest internal ureteral diameter., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Peritoneal dialysis (PD) technique survival is an important outcome for patients, caregivers and health professionals, however, the definition and measures used for technique survival vary. We aimed to assess the scope and consistency of definitions and measures used for technique survival in studies of patients receiving PD., Method: MEDLINE, EMBASE and CENTRAL databases were searched for randomised controlled studies (RCTs) conducted in patients receiving PD reporting technique survival as an outcome between database inception and December 2019. The definition and measures used were extracted and independently assessed by two reviewers., Results: We included 25 RCTs with a total of 3645 participants (41-371 per trial) and follow up ranging from 6 weeks to 4 years. Terminology used included 'technique survival' (10 studies), 'transfer to haemodialysis (HD)' (8 studies) and 'technique failure' (7 studies) with 17 different definitions. In seven studies, it was unclear whether the definition included transfer to HD, death or transplantation and eight studies reported 'transfer to HD' without further definition regarding duration or other events. Of those remaining, five studies included death in their definition of a technique event, whereas death was censored in the other five. The duration of HD necessary to qualify as an event was reported in only four (16%) studies. Of the 14 studies reporting causes of an event, all used a different list of causes., Conclusion: There is substantial heterogeneity in how PD technique survival is defined and measured, likely contributing to considerable variability in reported rates. Standardised measures for reporting technique survival in PD studies are required to improve comparability.

When infants are identified with a difference of sex development (DSD), a thoughtful approach to imaging is essential to appropriate clinical management. This review provides a comprehensive guide for radiologists who are tasked with performing this critical assignment. We review the embryologic basis of DSDs, with attention to the imaging findings that can indicate specific diagnoses. We also discuss techniques for optimal imaging, including strategies for identifying the gonads by US, tactics for performing genitograms with fluoroscopy and contrast-enhanced US, and the appropriate utilization of MRI. Finally, we review the clinical data and imaging findings that characterize some of the most common DSDs, including congenital adrenal hyperplasia, complete androgen insensitivity syndrome and gonadal dysgenesis., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In 2014, a multidisciplinary consensus on the classification of pre- and postnatal urinary tract dilation (UTD classification) was developed. Its goal was to provide a standardized system for evaluating and reporting urinary tract dilation both in the prenatal and postnatal periods. In this review, we summarize insights learned from the implementation of the UTD classification system since its inception, providing clarifications on common points of confusion. In addition, we review current literature in the clinical validation of the UTD classification system to provide credence for its use in managing fetuses and children with urinary tract dilation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

There is a growing demand for fast, accurate computation of clinical markers to improve renal function and anatomy assessment with a single study. However, conventional techniques have limitations leading to overestimations of kidney function or failure to provide sufficient spatial resolution to target the disease location. In contrast, the computer-aided analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) could generate significant markers, including the glomerular filtration rate (GFR) and time-intensity curves of the cortex and medulla for determining obstruction in the urinary tract. This paper presents a dual-stage fully modular framework for automatic renal compartment segmentation in 4D DCE-MRI volumes. (1) Memory-efficient 3D deep learning is integrated to localise each kidney by harnessing residual convolutional neural networks for improved convergence; segmentation is performed by efficiently learning spatial-temporal information coupled with boundary-preserving fully convolutional dense nets. (2) Renal contextual information is enhanced via non-linear transformation to segment the cortex and medulla. The proposed framework is evaluated on a paediatric dataset containing 60 4D DCE-MRI volumes exhibiting varying conditions affecting kidney function. Our technique outperforms a state-of-the-art approach based on a GrabCut and support vector machine classifier in mean dice similarity (DSC) by 3.8% and demonstrates higher statistical stability with lower standard deviation by 12.4% and 15.7% for cortex and medulla segmentation, respectively.

Ultrasound (US) has been increasingly used as an important imaging tool to assess the urethra in children. The earliest reports of pediatric urethral sonography involved imaging the urethra in a non-voiding state, during physiological voiding of urine, and after instillation of saline. The introduction of US contrast agents has continued to improve visualization of urethral anatomy. Contrast-enhanced US of the urethra can be performed during the voiding phase of a standard contrast-enhanced voiding urosonography (ceVUS) exam or with retrograde instillation of a contrast agent, depending on the exam indication. Both techniques are well tolerated by children and provide accurate information about urethral pathology and periurethral soft tissues. This article reviews the technical aspects and imaging findings of urethral pathologies in children using contrast-enhanced US, both by the voiding and retrograde instillation techniques., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Imaging plays a crucial role in evaluating newborns and infants with cloacal and urogenital malformations. Contrast-enhanced genitosonography (ceGS) and contrast-enhanced colosonography (ceCS) are sensitive and radiation-free alternatives to fluoroscopic genitography and colography for diagnosis and surgical planning. These imaging techniques are performed by instilling a US contrast agent into specific body cavities to define the genitourinary and colorectal anatomy. This review article presents the experience with ceGS and ceCS applications in children, focusing on the background, examination technique, and interpretation of imaging findings, as well as strengths and weaknesses compared to conventional techniques., (© 2020. Springer-Verlag GmbH Germany, part of Springer Nature.)

Contrast-enhanced voiding urosonography (ceVUS) is a well-established, sensitive and safe ultrasound (US) modality for detecting and grading vesicoureteral reflux (VUR) and urethral imaging in children. Nearly three decades of remarkable advances in US technology and US contrast agents have refined ceVUS's diagnostic potential. The recent approval of Lumason/SonoVue in the United States, Europe and China for pediatric intravesical applications marked the beginning of a new era for this type of contrast US imaging. Consequently, the use of ceVUS in children has expanded to multiple places around the globe. In the first part of this review article, we describe the current experience in the use of ceVUS for VUR evaluation, with an emphasis on historical background, examination technique, image interpretation and diagnostic accuracy. In the second part, we will present the role of ceVUS for urethral imaging in children., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Background and Objective: We evaluated inattention and behavioural outcomes following surgery versus watchful waiting (WW) in school-aged children with mild obstructive sleep apnoea (OSA)., Methods: A prospective randomized controlled study was performed in pre-pubertal children aged 6-11 years with polysomnography (PSG)-confirmed mild OSA. They were assigned randomly to early surgical intervention (ES) or WW. The surgical intervention consisting of tonsillectomy with or without adenoidectomy and turbinate reduction was carried out within 4-6 weeks after randomization. Both groups underwent PSG, attention and behavioural assessment and review by an otorhinolaryngologist at baseline and 9-month follow-up. The primary outcome was omission T score from Conners' continuous performance test (CPT). Secondary outcomes were parent-reported behaviours, quality of life, symptoms and PSG parameters., Results: A total of 114 participants were randomized. Data of 35 subjects from the ES and 36 from the WW group were available for final analysis. No significant treatment effect could be found in all CPT parameters and behavioural outcomes. Nevertheless, significantly greater reductions were seen in PSG parameters (obstructive apnoea-hypopnoea index [-1.4 ± 2.0 cf. +0.3 ± 4.1/h, p = 0.038] and arousal index [-1.3 ± 4.4 cf. +1.4 ± 4.5/h, p = 0.013]) and OSA-18 total symptom score (-17.3 ± 19.7 cf. -3.6 ± 14.1, p = 0.001) in the ES group. Subjects who underwent surgery also had significantly greater weight gain (+3.3 ± 2.1 cf. +2.2 ± 1.5 kg, p = 0.014) and increase in systolic blood pressure (+5.1 ± 12.4 cf. -1.2 ± 8.7 mm Hg, p = 0.016)., Conclusion: Despite improvements in PSG parameters and parent-reported symptoms, surgical treatment did not lead to parallel improvements in objective attention measures in school-aged children with mild OSA., (© 2021 Asian Pacific Society of Respirology.)

Early identification of kidney function deterioration is essential to determine which newborn patients with congenital kidney disease should be considered for surgical intervention as opposed to observation. Kidney function can be measured by fitting a tracer kinetic (TK) model onto a series of Dynamic Contrast Enhanced (DCE) MR images and estimating the filtration rate parameter from the model. Unfortunately, breathing and large bulk motion events due to patient movement in the scanner create outliers and misalignments that introduce large errors in the TK model parameter estimates even when using a motion-robust dynamic radial VIBE sequence for DCE-MR imaging. The misalignments between the series of volumes are difficult to correct using standard registration due to 1) the large differences in geometry and contrast between volumes of the dynamic sequence and 2) the requirement of fast dynamic imaging to achieve high temporal resolution and motion deteriorates image quality. These difficulties reduce the accuracy and stability of registration over the dynamic sequence. An alternative registration approach is to generate noise and motion free templates of the original data from the TK model and use them to register each volume to its contrast-matched template. However, the TK models used to characterize DCE-MRI are tissue specific, non-linear and sensitive to the same motion and sampling artifacts that hinder registration in the first place. Hence, these can only be applied to register accurately pre-segmented regions of interest, such as kidneys, and might converge to local minima under the presence of large artifacts. Here we introduce a novel linear time invariant (LTI) model to characterize DCE-MR data for different tissue types within a volume. We approximate the LTI model as a sparse sum of first order LTI functions to introduce robustness to motion and sampling artifacts. Hence, this model is well suited for registration of the entire field of view of DCE-MR data with artifacts and outliers. We incorporate this LTI model into a registration framework and evaluate it on both synthetic data and data from 20 children. For each subject, we reconstructed the sequence of DCE-MR images, detected corrupted volumes acquired during motion, aligned the sequence of volumes and recovered the corrupted volumes using the LTI model. The results show that our approach correctly aligned the volumes, provided the most stable registration in time and improved the tracer kinetic model fit., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Introduction: Understanding details of anatomic relationships between the colon and surrounding structures is a critical piece of preoperative planning prior to surgical repair of anorectal malformations (ARMs). Traditional imaging techniques involve ionizing radiation, distention of the rectum with supraphysiologic intraluminal pressures, and sometimes require sedation. Recent developments in the field of contrast agents have allowed the emergence of an ultrasound-based technique that can avoid these requirements while continuing to provide high resolution structural information in three dimensions., Methods: Fourteen children (13 male, 1 female, age 1-11 months) with ARMs underwent contrast enhanced colostography (ceCS) in addition to traditional preoperative imaging techniques to delineate anatomic relationships of pelvic structures., Results: ceCS and traditional imaging yielded concordant anatomic information, including structural relationships and fistulous connections, in 10/14 patients (71%). ceCS detected fistulous connection in 2/13 patients (15%) that were not seen by traditional imaging. Ultrasonography failed to detect the fistulous connection in one patient., Conclusions: ceCS is a safe, effective and flexible method for defining important structural information in ARM patients. When compared with traditional methods, it provided equivalent or superior results 93% of the time and bears consideration as a standard tool in preoperative planning for this population., Type of Study: Retrospective Comparative Study., Level of Evidence: Level III., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Introduction: The Urinary Tract Dilation (UTD) system was created to address variability in hydronephrosis grading. It is unknown if or how pediatric urologists are integrating this newer system into practice., Objective: We sought to evaluate the current use of hydronephrosis grading systems, inter-rater reliability (IRR) for individual systems, and management preferences based on degree of hydronephrosis., Study Design: A survey was emailed to the Societies for Pediatric Urology listserv. Questions addressed familiarity/preference for various grading systems and respondent confidence in interpretation of hydronephrosis. Three clinical vignettes asked respondents to grade hydronephrosis using their system of choice and report further imaging they would obtain. Descriptive statistics were calculated, and IRR was calculated using a linear-weighted modified Fleiss' kappa test., Results: Response rate was 43% (n = 138). The majority of respondents used Society for Fetal Urology (SFU) (70%) or UTD (19%) systems. Most favored SFU (58%) or UTD (34%) systems for a unified system. Confidence in own interpretation was higher than confidence in radiologists' reads (median 4.4 vs 3.6, p < 0.001). IRR was substantial for UTD (κ0.68 [0.64-0.71]) and moderate for SFU (κ0.60 [0.52-0.76]). There was notable heterogeneity regarding follow-up imaging for cases. There was no difference in requested follow-up studies between SFU and UTD systems, except for fewer voiding cystourethrogram (VCUG) requests for Case 3 with UTD (28% vs 4%, p = 0.02)., Conclusion: Most pediatric urologists still use SFU rather than the UTD system. There was slightly higher IRR with the UTD system. There was substantial variability in follow-up imaging not related to grading system, except with low grade hydronephrosis., (Copyright © 2020 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: Evaluation of kidney function in newborns with hydronephrosis is important for clinical decisions. Dynamic contrast-enhanced (DCE) MRI can provide the necessary anatomical and functional information. Golden angle dynamic radial acquisition and compressed sensing reconstruction provides sufficient spatiotemporal resolution to achieve accurate parameter estimation for functional imaging of kidneys. However, bulk motion during imaging (rigid or nonrigid movement of the subject resulting in signal dropout) remains an unresolved challenge., Purpose: To evaluate a motion-compensated (MoCo) DCE-MRI technique for robust evaluation of kidney function in newborns. Our method includes: 1) motion detection, 2) motion-robust image reconstruction, 3) joint realignment of the volumes, and 4) tracer-kinetic (TK) model fitting to evaluate kidney function parameters., Study Type: Retrospective., Subjects: Eleven newborn patients (ages <6 months, 6 female)., Field Strength/sequence: 3T; dynamic "stack-of-stars" 3D fast low-angle shot (FLASH) sequence using a multichannel body-matrix coil., Assessment: We evaluated the proposed technique in terms of the signal-to-noise ratio (SNR) of the reconstructed images, the presence of discontinuities in the contrast agent concentration time curves due to motion with a total variation (TV) metric and the goodness of fit of the TK model, and the standard variation of its parameters., Statistical Tests: We used a paired t-test to compare the MoCo and no-MoCo results., Results: The proposed MoCo method successfully detected motion and improved the SNR by 3.3 (P = 0.012) and decreased TV by 0.374 (P = 0.017) across all subjects. Moreover, it decreased nRMSE of the TK model fit for the subjects with less than five isolated bulk motion events in 6 minutes (mean 1.53, P = 0.043), but not for the subjects with more frequent events or no motion (P = 0.745 and P = 0.683)., Data Conclusion: Our results indicate that the proposed MoCo technique improves the image quality and accuracy of the TK model fit for subjects who present isolated bulk motion events., Level of Evidence: 3 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2020;52:207-216., (© 2019 International Society for Magnetic Resonance in Medicine.)

Background: Current methods to estimate glomerular filtration rate (GFR) have shortcomings. Estimates based on serum creatinine are known to be inaccurate in the chronically ill and during acute changes in renal function. Gold standard methods such as inulin and 99m Tc diethylenetriamine pentaacetic acid (DTPA) require blood or urine sampling and thus can be difficult to perform in children. Motion-robust radial volumetric interpolated breath-hold examination (VIBE) dynamic contrast-enhanced MRI represents a novel tool for estimating GFR that has not been validated in children., Objective: The purpose of our study was to determine the feasibility and accuracy of GFR measured by motion-robust radial VIBE dynamic contrast-enhanced MRI compared to estimates by serum creatinine (eGFR) and 99m Tc DTPA in children., Materials and Methods: We enrolled children, 0-18 years of age, who were undergoing both a contrast-enhanced MRI and nuclear medicine 99m Tc DTPA glomerular filtration rate (NM-GFR) within 2 weeks of each other. Enrolled children consented to an additional 6-min dynamic contrast-enhanced MRI scan using the motion-robust high spatiotemporal resolution prototype dynamic radial VIBE sequence (Siemens, Erlangen, Germany) at 3 tesla (T). The images were reconstructed offline with high temporal resolution (~3 s/volume) using compressed sensing image reconstruction including regularization in temporal dimension to improve image quality and reduce streaking artifacts. Images were then automatically post-processed using in-house-developed software. Post-processing steps included automatic segmentation of kidney parenchyma and aorta using convolutional neural network techniques and tracer kinetic model fitting using the Sourbron two-compartment model to calculate the MR-based GFR (MR-GFR). The NM-GFR was compared to MR-GFR and estimated GFR based on serum creatinine (eGFR) using Pearson correlation coefficient and Bland-Altman analysis., Results: Twenty-one children (7 female, 14 male) were enrolled between February 2017 and May 2018. Data from six of these children were not further analyzed because of deviations from the MRI protocol. Fifteen patients were analyzed (5 female, 10 male; average age 5.9 years); the method was technically feasible in all children. The results showed that the MR-GFR correlated with NM-GFR with a Pearson correlation coefficient (r-value) of 0.98. Bland-Altman analysis (i.e. difference of MR-GFR and NM-GFR versus mean of NM-GFR and MR-GFR) showed a mean difference of -0.32 and reproducibility coefficient of 18 with 95% confidence interval, and the coefficient of variation of 6.7% with values between -19 (-1.96 standard deviation) and 18 (+1.96 standard deviation). In contrast, serum creatinine compared with NM-GFR yielded an r-value of 0.73. Bland-Altman analysis (i.e. difference of eGFR and NM-GFR versus mean of NM-GFR and eGFR) showed a mean difference of 2.9 and reproducibility coefficient of 70 with 95% confidence interval, and the coefficient of variation of 25% with values between -67 (-1.96 standard deviation) and 73 (+1.96 standard deviation)., Conclusion: MR-GFR is a technically feasible and reliable method of measuring GFR when compared to the reference standard, NM-GFR by serum 99m Tc DTPA, and MR-GFR is more reliable than estimates based on serum creatinine.

In this case series, contrast enhanced genitosonography is compared to genitography performed using fluoroscopy and cone-beam computed tomography in patients with urogenital sinus and the cloacal malformation. The method of contrast enhanced genitosonography is described, including contrast preparation, contrast administration, ultrasound imaging approaches, as well as the benefits and potential pitfalls of this technique compared to fluoroscopy and computed tomography., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: There is substantial variation in peritonitis rates across peritoneal dialysis (PD) units globally. This may, in part, be related to the wide variability in the content and delivery of training for PD nurse trainers and patients., Aim: The aim of this study was to test the feasibility of implementing the Targeted Education ApproaCH to improve Peritoneal Dialysis Outcomes (TEACH-PD) curriculum in real clinical practice settings., Methods: This study used mixed methods including questionnaires and semi-structured interviews (pretraining and post-training) with nurse trainers and patients to test the acceptability and usability of the PD training modules implemented in two PD units over 6 months. Quantitative data from the questionnaires were analysed descriptively. Interviews were analysed using thematic analysis., Results: Ten PD trainers and 14 incident PD patients were included. Mean training duration to complete the modules were 10.9 h (range 6-17) and 24.9 h (range 15-35), for PD trainers and patients, respectively. None of the PD patients experienced PD-related complications at 30 days follow-up. Three (21%) patients were transferred to haemodialysis due to non-PD-related complications. Ten trainers and 14 PD patients participated in the interviews. Four themes were identified including use of adult learning principles (trainers), comprehension of online modules (trainers), time to complete the modules (trainers) and patient usability of the manuals (patient)., Conclusion: This TEACH-PD study has demonstrated feasibility of implementation in a real clinical setting. The outcomes of this study have informed refinement of the TEACH-PD modules prior to rigorous evaluation of its efficacy and cost-effectiveness in a large-scale study.

Objective: To describe a technique for performing magnetic resonance urogram (MRU) in infants without sedation or anesthesia., Methods: Eighteen infants underwent MRU in the absence of sedating medications using a 'feed and wrap' technique (FW-MRU). Dynamic contrast enhanced images were obtained. Dynamic radial VIBE and compressed sensing image reconstruction were used to correct for motion artifact., Results: Seventeen of the 18 patients had successful FW-MRU. Feed and wrap' magnetic resonance urogram provided high-quality anatomic and functional renal data., Conclusion: Initial experience with FW-MRU demonstrates it to be a promising anesthesia-free modality for obtaining anatomic and functional imaging of the urinary tract in infants., (Copyright © 2019 Journal of Pediatric Urology Company. All rights reserved.)

This case series describes a novel method for showing the preoperative anatomy of children with anorectal malformations using ultrasound contrast, which we have termed "contrast-enhanced colosonography (ceCS)." Six patients with anorectal malformations without a perineal fistula were studied both by fluoroscopic distal colostography and ceCS, and their results were confirmed surgically. Contrast-enhanced CS precisely showed the complex anatomic relationships in all cases. Compared to traditional fluoroscopic studies, ceCS has the benefit of no associated ionizing radiation and thus is safer for children., (© 2019 by the American Institute of Ultrasound in Medicine.)

Background: There are limited data on the predictive value of the consensus urinary tract dilation (UTD) score with respect to subsequent clinical diagnoses. We sought to define the relationship between postnatal UTD risk score and clinical outcomes during childhood., Methods: Complete ultrasound image sets from a random selection of infants aged 0-90 days undergoing initial ultrasound at a single institution for prenatal hydronephrosis between 2012 and 2014 were assigned a UTD score by 1 pediatric urologist and 1 pediatric radiologist. Urinary tract dilation risk score was analyzed for association with a composite outcome comprising urinary tract infection, vesicoureteral reflux (VUR), ureteropelvic junction obstruction, non-refluxing megaureter (NRM), ureterocele, bladder outlet obstruction (BOO), and chronic kidney disease. Surgical intervention and resolution of UTD were evaluated separately. Descriptive and survival analyses were performed., Results: Urinary tract dilation scores for 494 subjects were P0 in 23.5%, P1 in 26.5%, P2 in 23.5%, and P3 in 26.5%. Seventy-four percent were male. Median age at initial imaging was 28 days; median follow-up was 19.8 months. The composite outcome occurred in 138 of 494 patients (27.9%) and varied significantly (p < 0.001) by UTD score: 11.2% for P0, 10.7% for P1, 29.3% for P2, and 58.8% for P3. On survival analysis (Summary Figure), higher UTD grade was significantly associated with the composite outcome (hazard ratio for P3 vs. P0 was 7.4 [95% CI: 3.44-15.92, p < 0.001]). Urinary tract infection and VUR diagnosis varied by UTD score (p = 0.03 and p < 0.001, respectively). Ureteropelvic junction obstruction was diagnosed (based on MAG3 results) in 6.3% of patients, 84% of whom were P3. Non-refluxing megaureter was diagnosed in 7.7%. Ureterocele and BOO were uncommon (1.4%, and 0.6%, respectively). Surgical intervention was also associated with UTD risk, with 46% of P3 undergoing surgery vs. 1% of P0, 1% of P1, and 6% of P2 (p < 0.001). Resolution of UTD occurred in 41% (median 10.1 months) and varied significantly by UTD risk (p < 0.001)., Discussion: Urinary tract dilation risk score is associated with clinical events, although ascertainment bias may influence some of the differences in outcomes, particularly for VUR, because VCUG utilization varied by the UTD group. The lack of any significant difference in outcomes between patients with UTD P0 versus P1 suggests that the P1 category could be eliminated as it does not meaningfully distinguish between outcome risk., Conclusions: Higher UTD risk scores are strongly associated with genitourinary diagnoses during the first two years of life., (Copyright © 2019 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Objectives: This paper reports the utilization of intraoperative ultrasound in the removal of an accidentally ingested wire grill-brush bristle from the pharyngeal space of a child., Methods: Standard procedures for obtaining imaging of an accidentally ingested foreign body were performed, including radiograph, computed tomography (CT) imaging, and preoperative ultrasonography. Despite preoperative imaging, the object could neither be located nor removed. Ultrasonography was performed intraoperatively for real-time localization., Results: Intraoperative ultrasonography was required to successfully locate and remove the wire grill-brush bristle from the patient's oropharyngeal space., Conclusions: Intraoperative ultrasound serves as a useful tool to guide surgical removal of aerodigestive foreign bodies and may offer an opportunity to reduce the need for CT imaging.

Purpose: The Urinary Tract Dilation classification system was designed to be more objective and reproducible than currently available grading systems. We evaluated the reliability and consistency of the system in newborns., Materials and Methods: Of 1,046 infants 0 to 90 days old undergoing ultrasound for hydronephrosis 243 were randomly selected for study inclusion. Seven readers (4 radiologists and 3 urologists) at 4 institutions classified complete, de-identified ultrasound studies on a Web based platform. Interobserver and intra-observer agreement was evaluated using the Fleiss kappa statistic., Results: Interobserver agreement for Urinary Tract Dilation risk score was moderate among the 7 readers (kappa = 0.421, 95% CI 0.404-0.438). Interobserver agreement using the Society for Fetal Urology scale was worse than with the Urinary Tract Dilation classification (kappa = 0.344, 95% CI 0.330-0.359). All 7 readers assigned the same Urinary Tract Dilation score in 19.3% of cases (47 of 243). In 38.7% of cases (94 of 243) at least 3 readers assigned a Urinary Tract Dilation score different from that assigned by the other readers. In 7% of cases (17 of 243) at least 3 readers assigned a score of P0/P1, while at least 3 readers scored the same cases as P2/P3. At least 3 different Urinary Tract Dilation risk scores were assigned to the same patient in 30.45% of patients (74 of 243). Among individual Urinary Tract Dilation elements calyceal dilatation and bladder status had the highest disagreement. Five readers regraded 80 cases and agreed with their previous Urinary Tract Dilation risk score in 63.8% to 75.0% of cases (kappa 0.458 to 0.729)., Conclusions: Interobserver agreement using the Urinary Tract Dilation grading system is fair to moderate, with variable agreement on individual elements of the system. Agreement was higher for the Urinary Tract Dilation system compared to the Society for Fetal Urology scale.

Paraneoplastic syndromes are defined as clinical syndromes that are not related to direct tumor invasion or compression but are secondary to tumor secretion of functional peptides/hormones or related to immune cross-reactivity with normal host tissue. Paraneoplastic syndromes have a wide range of presentations and can present before the primary malignancy or tumor recurrence is diagnosed. They can mimic non-neoplastic processes, making detection, diagnosis and treatment difficult. However, they can also provide clues to the presence of an underlying malignancy. In this paper, we reviewed a range of paraneoplastic syndromes that can occur in children including: (1) neurologic (opsoclonus-myoclonus, limbic, anti-N-methyl-d-aspartate [NMDA] and anti-Ma2 encephalitis and myasthenia gravis); (2) endocrine (neuroendocrine tumors, hypercalcemia, SIADH [syndrome of inappropriate antidiuretic hormone secretion], osteomalacia/rickets and ROHHAD [rapid onset of obesity, hypoventilation, hypothalamic dysfunction and autonomic dysregulation]); and (3) dermatologic/rheumatologic syndromes (hypertrophic osteoarthropathy and paraneoplastic pemphigus). Familiarity with these syndromes can aid in early diagnosis, treatment and imaging optimization.

Introduction: Stress urinary incontinence (SUI) is common among older multiparous females but rarely reported in active, young girls., Objectives: Our hypothesis is: physically active adolescent females develop pelvic floor laxity demonstrable on upright VCUG. Our objectives are to (1) increase awareness of SUI in young females, (2) test our hypothesis with an upright VCUG, and (3) report effectiveness of step-wise management., Study Design: A retrospective review was performed of nulliparous girls with only SUI seen from 2000 to 2015, who were evaluated with upright voiding cystourethrography (VCUG) (bladder descent defined as ≥2 cm drop of bladder neck below pubic ramus at capacity). Data collection included level of physical activity, physical examination, BMI and Z-scores, urodynamics, management, and treatment response. Standard urotherapy (SUT) (timed voiding, proper diet, adequate fluids, bowel management) and biofeedback therapy (BFT) was initiated. Fisher exact test was used to calculate 'p' values., Results: Thirty-three females (median age 15.1 years, range 5.5-20.3) were identified who underwent an upright VCUG; 20 had bladder neck descent (Fig.). Of these 20, 15 (75%) were involved in strenuous activity, whereas only three of 13 (23%) without descent engaged in intense athletics. No differences were noted in median BMI and Z-score with strenuous activity (21.1 (15.2-26.7) and 0.31 (-0.9-1.94)), respectively, versus patients without (21.3 (15.8-33.5) and 0.62 (-0.0-2.38)). Average follow-up for all was 16.6 months (range 0.4-102.2). Of 20 demonstrating bladder neck descent, three did not complete therapy and were lost to follow-up. Only six of these 17 became dry. Of the remaining 11, eight underwent surgery: Burch colposuspension (5), fascial sling (2), Coaptite to the bladder neck (1), and an artificial urinary sphincter (1). This latter girl had a failed Burch colposuspension 1 year previously. All surgical patients are dry. Of 13 without bladder descent on VCUG, five did not complete therapy and were lost to follow-up. The remaining eight were managed non-surgically; seven were fully dry at last follow-up. Overall, 13 of 25 (52%) achieved dryness. SUT and BFT were more effective in those without, than in those with bladder descent (87.5% vs. 35.3%, p = 0.0302, Fisher exact test)., Discussion and Conclusions: Physically active, nulligravid girls with SUI can be efficaciously diagnosed on upright VCUG. They should be considered for non-surgical therapy but will likely require bladder neck elevating surgery. Non-surgical therapy works for those with minimal bladder descent on cystography., (Copyright © 2018 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Background: Fluoroscopy is commonly used during pediatric ureteroscopy (PURS) for urolithiasis, and the most important contributor to overall radiation exposure is fluoroscopy time (FT). One factor that may impact FT is who controls activation of the fluoroscope: the urologist (with a foot pedal) or the radiation technologist (as directed by the urologist). While there are plausible reasons to believe that either approach may lead to reduced FT, there are no systematic investigations of this question. We sought to compare FT with surgeon-control versus technologist control during PURS for urolithiasis., Methods: We conducted a randomized controlled trial (Clinicaltrials.gov ID number: NCT02224287). Institutional Review Board approval was sought and obtained for this study. All subjects (or their legal guardians) provided informed consent. Each patient (age 5-26 years) was randomized to surgeon- or technologist-controlled fluoroscope activation. Block randomization was stratified by the surgeon. For technologist control, the surgeon verbally directed the technologist to activate the fluoroscope. For surgeon control, a foot pedal was used by the surgeon. The technologist controlled c-arm positioning, settings, and movement. The primary outcome was total FT for the procedure. Secondary outcomes included radiation exposure (entrance surface air kerma [ESAK] mGy). We also analyzed clinical and procedural predictors of FT and exposure. Mixed linear models accounting for clustering by surgeon were developed., Results: Seventy-three procedures (5 surgeons) were included. The number of procedures per surgeon ranged from seven to 36. Forty-three percent were pre-stented. Thirty-one procedures were left side, 35 were right side, and seven were bilateral. Stones were treated in 71% of procedures (21% laser, 14% basket, and 65% laser/basket). Stone locations were distal ureter (11.5%), proximal/mid-ureter (8%), renal (69%), and ureteral/renal (11.5%). An access sheath was used in 77%. Median stone size was 8.0 mm (range 2.0-20.0). Median FT in the surgeon control group was 0.5 min (range 0.01-6.10) versus 0.55 min (range 0.10-5.50) in the technologist-control group (p = 0.284). Median ESAK in the surgeon control group was 46.02 mGy (range 5.44-3236.80) versus 46.99 mGy (range: 0.17-1039.31) in the technologist-control group (p = 0.362). Other factors associated with lower FT on univariate analysis included female sex (p = 0.015), no prior urologic surgeries (p = 0.041), shorter surgery (p = 0.011), and no access sheath (p = 0.006). On multivariable analysis only female sex (p = 0.017) and no access sheath (p = 0.049) remained significant. There was significant variation among surgeons (p < 0.0001); individual surgeon median FT ranged from 0.40 to 2.95 min., Conclusions: Fluoroscopy time and radiation exposure are similar whether the surgeon or technologist controls fluoroscope activation. Other strategies to reduce exposure might focus on surgeon-specific factors, given the significant variation between surgeons., (Copyright © 2018 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.)

Catheters are commonly used to treat and diagnose urinary tract abnormalities in the pediatric population. This pictorial essay reviews commonly placed genitourinary catheters imaged by radiography, fluoroscopy, computed tomography (CT) and ultrasonography (US). The purpose of the catheter, how the catheter is placed, and the imaging findings associated with appropriately positioned catheters as well as misplaced and displaced catheters are described. It is important for radiologists to recognize common genitourinary catheters, and be familiar with their normal and abnormal positions as displacement is often first recognized by diagnostic imaging.

A 3-month-old premature male infant with imperforate anus and hypospadias underwent contrast-enhanced voiding urosonography (ceVUS) followed by voiding cystourethrography (VCUG). Images from the ceVUS demonstrated a distinct linearity arising dorsally from the posterior urethra that partially opacified with contrast. VCUG confirmed a urethral duplication. To our knowledge, this exceedingly rare anomaly has yet to be reported by ceVUS., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Background: International guidelines recommend treatment of anaemia due to chronic kidney disease (CKD) with erythropoiesis-stimulating agents (ESAs)., Objective: To document the time required and the cost in terms of nursing time to prepare and administer ESAs to patients on facility based haemodialysis (HD) with anaemia due to CKD before and after the introduction of long-acting ESAs., Design: A time and motion study was implemented at four HD units in Australia to determine the time and costs associated with preparing and administering ESAs before and after the introduction of long-acting ESAs., Participants: This was a prospective, observational study of workplace practices at four HD units in Australia., Measurements: Outcome data included the time taken to prepare, and administer ESAs., Results: The time costs of preparation and administration per patient per year had a wide variability within each unit and ranged from Australian AUD$55.75 (38 euros) to AUD$90.49 (62 euros) before the introduction of long-acting ESAs. This dropped by 73-80% following the introduction of long-acting ESAs, representing an annual cost savings of between AUD$2,591 and AUD$5,914 if all patients on HD were switched to a long acting ESA., Conclusion: Switching from a short-acting to a long-acting ESA in HD units leads to a significant reduction in time costs of health professionals in preparation and administration of ESAs by up to 80%. Practical application: This time and motion study has added further evidence on reduction of human effort by taking advantages of new research development, such as the long acting ESAs., (© 2017 European Dialysis and Transplant Nurses Association/European Renal Care Association.)

Duplication anomalies of the urinary collecting system are common and can be discovered and characterized with multiple imaging modalities. The embryology, imaging manifestations and clinical ramifications of duplicated ureters and renal collecting systems vary from a normal anatomical variant to urological pathology and are discussed and illustrated in this review.

The multidisciplinary consensus on the classification of prenatal and postnatal urinary tract dilation (UTD classification system) was created to unify the language used to describe urinary tract dilation on antenatal and postnatal ultrasound examinations and thereby facilitate communication among providers and improve outcomes research. The background and new classification system are described in this review, with imaging examples.

Introduction: Voiding cystourethrogram (VCUG) provides a wealth of data on urinary tract function and anatomy, but few standards exist for reporting VCUG findings., Objective: We aimed to assess variability in VCUG reports and to test our hypothesis that VCUG reports from pediatric facilities and pediatric radiologists are more complete than those performed at other facilities or by non-pediatric radiologists., Study Design: We analyzed original VCUG reports from children enrolled in the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) trial. A 23-item checklist was created and used to evaluate reporting of technical (e.g. catheter size), anatomic (e.g. vesicoureteral reflux (VUR) presence and grade, bladder shape), and functional information (e.g. bladder emptying). Radiologists were classified as pediatric or non-pediatric radiologists. Facilities were categorized as to whether they were a free-standing pediatric hospital (FSPH), a pediatric "hospital within a hospital" (PHWH), a non-pediatric hospital (NPH), or an outpatient radiology facility (ORF). Multivariate linear regression was used to analyze factors associated with the completeness of the VCUG reports (percent of items reported from the 23-item checklist)., Results: Six-hundred and two VCUGs were performed at 90 institutions. Of those, 76% were read by a pediatric radiologist, and 49% were performed at a FSPH (Table). On average, less than half of the 23 items in our standardized assessment tool were included in VCUG reports (mean 48%, SD 12). The completeness of reports varied by facility type: 51% complete at FSPH (SD 11), 50% at PHWH (SD 10), 36% at NPH (SD 11), and 43% at ORF (SD 8) (p < 0.0001). In multivariate analysis, VCUG reports generated at NPH or ORF had 8% fewer items included (95% CI 3.0-12.8, p < 0.01), and those generated at PHWH did not differ from those generated at FSPH. Reports read by a non-pediatric radiologist had 6% fewer items included (95% CI 3-9.7; p < 0.01) compared with those read by a pediatric radiologist., Discussion: There is substantial underreporting of findings in VCUG reports when assessing a widely represented sample of routine, community-generated reports using an idealized standard. Although VUR was often reported, other crucial anatomic and functional findings of the VCUG were consistently underreported across all facility types., Conclusion: Although pediatric radiologist and pediatric hospitals generated more complete VCUG reports compared with those having non-pediatric origins, the differences are small when considering the substantial underreporting of VCUG findings in general. This underscores the opportunities for improvement in reporting of VCUG findings., (Copyright © 2016. Published by Elsevier Ltd.)

Introduction: Voiding cystourethrography (VCUG) is the modality of choice to diagnose vesicoureteral reflux (VUR). Although grading of VUR is essential for prognosis and clinical decision-making, the inter-observer reliability for grading has been shown to vary substantially. The Randomized Intervention for Children with VesicoUreteral Reflux (RIVUR) trial provides a large cohort of children with VUR to better understand the reliability of VCUG findings., Objective: To determine the inter-observer consistency of the grade of VUR and other VCUG findings in a large cohort of children with VUR., Study Design: The RIVUR trial is a randomized controlled trial of antimicrobial prophylaxis in children with VUR diagnosed after UTI. Each enrollment VCUG was read by a local clinical (i.e. non-reference) radiologist, and independently by two blinded RIVUR reference radiologists. Reference radiologists' disagreements were adjudicated for trial purposes. The grade of VUR and other VCUG findings were extracted from the local clinical radiologist's report. The unit of analysis included individual ureters and individual participants. We compared the three interpretations for grading of VUR and other VCUG findings to determine the inter-observer reliability., Results: Six-hundred and two non-reference radiology reports from 90 institutions were reviewed and yielded the grade of VUR for 560 left and 524 right ureters. All three radiologists agreed on VUR grade in only 59% of ureters; two of three agreed on 39% of ureters; and all three disagreed on 2% of ureters (Table). Agreement was better (≥92%) for other VCUG findings (e.g. bladder shape "normal"). The non-reference radiologists' grade of VUR differed from the reference radiologists' adjudicated grade by exactly one grade level in 19% of ureters, and by two or more grade levels in 2.2% of ureters. When the participant was the unit of analysis, all three radiologists agreed on the grade of VUR in both ureters in just 43% of cases., Discussion: Our study shows considerable and clinically relevant variability in grading VUR by VCUG. This variability was consistent when comparing non-reference to the adjudicated reference radiologists' assessment and the reference radiologists to each other. This study was limited to children with a history of UTI and grade I-IV VUR and may not be generalizable to all children who have a VCUG., Conclusion: The considerable inter-observer variability in VUR grading has both research and clinical implications, as study design, risk stratification, and clinical decision-making rely heavily on grades of VUR., (Copyright © 2016 Journal of Pediatric Urology Company. All rights reserved.)

Pediatric urolithiasis is an important and increasingly prevalent cause of pediatric morbidity and hospital admission. Ultrasound (US) is the recommended primary imaging modality for suspected urolithiasis in children. There is, however, widespread use of CT as a first-line study for abdominal pain in many institutions involved in pediatric care. The objective of this review is to outline state-of-the-art imaging modalities and methods for diagnosing urolithiasis in children. The pediatric radiologist plays a key role in ensuring that the appropriate imaging modality is performed in the setting of suspected pediatric urolithiasis. Our proposed imaging algorithm starts with US, and describes the optimal technique and indications for the use of CT. We emphasize the importance of improved communication with a greater collaborative approach between pediatric and general radiology departments so children undergo the appropriate imaging evaluation.

Objective: To determine the mean and normal range of anteroposterior diameter (APD) of the renal pelves in children., Methods: Patients aged 0-19 years with normal spinal MRIs were identified after institutional review board approval. Those with dilating uropathy or abdominal surgery/radiation were excluded. The maximum APD was measured. A mixed linear model was fit to determine the relationship between APD and age, adjusted for bladder distention. The left and right kidneys were treated independently., Results: 283 left and 285 right renal units were included. For the left, a 3.5% increase in APD per year was predicted (p < 0.0001), with the average APD for infants and 18-year olds with non-distended bladders being 2.5 mm (95th percentile: 7.2 mm) and 4.6 mm (13.4 mm), respectively. For the right, a 3.9% increase in APD per year was predicted (p < 0.0001), with the average APD for infants and 18-year olds with non-distended bladders being 2.8 mm (8.4 mm) and 5.5 mm (16.6 mm), respectively. Compared with a non-distended bladder, a distended bladder increased the predicted APD between 23% (right) and 38% (left) (p = 0.01 and p < 0.0001, respectively)., Conclusion: The mean and normal ranges of APD measured by MRI in children are provided. APD increases with age and bladder distension and is greater on the left. Advances in knowledge: This article establishes normative ranges for APD, a critical component of genitourinary tract evaluation, and does so using the most precise imaging modality for this condition.

A 9-month-old girl underwent conventional cyclic voiding cystourethrography (VCUG) followed immediately by cyclic contrast-enhanced voiding urosonography (ceVUS). Although the VCUG showed unilateral grade II reflux, the ceVUS showed no reflux. Images from the ceVUS showed posterior dependent layering of the denser iodinated contrast in the bladder. This layering likely prevented reflux of US microbubbles resulting in a false-negative ceVUS. To our knowledge, this potential pitfall has not yet been reported.