Ureteral stent extraction strings in children: Stratifying the risk of post operative urinary tract infection

INTRODUCTION

Ureteral stents facilitate recovery and avoid external drains in pediatric ureteral reconstruction. Extraction strings avoid the need for a secondary cystoscopy and anesthetic. Due to concerns regarding febrile UTIs in children with extraction strings, we retrospectively assessed the relative risk of UTI in children with extraction strings.

OBJECTIVE

Our hypothesis was that stents with extraction strings do not increase the risk of UTI after pediatric ureteral reconstruction.

METHODS

Records of all children undergoing pyeloplasty and ureteroureterostomy (UU) from 2014 to 2021 were reviewed. The incidences of UTI, fever, and hospitalization were recorded.

RESULTS

245 patients mean age 6.4 years (163M:82F) underwent pyeloplasty (n = 221) or UU (n = 24). 42% (n = 103) received prophylaxis. Of these, 15% developed UTI versus 5% of those not receiving prophylaxis (p < 0.05). 42 females had prior history of UTI, compared to 20 males (p < 0.05). 49 patients had an extraction string. Stents with extraction strings were removed on average 0.6 months post-op while others underwent cystoscopic removal on average 1.26 months post-op (p < 0.05). 9 (18.4%) required hospitalization for febrile UTI while the stent with extraction string was in place, while only 13 (6.6%) of those without extraction string did (p < 0.02). Of the 9 children with a febrile UTI in the extraction string group, 6 had history of prior UTI (46.1%), compared to only 3 (8.3%) without a prior UTI (p < 0.05). With no prior UTI, there was no difference in UTI risk between those with (3, 8.3%) and without (8, 6.4%) extraction string (p = 0.71). Females with prior UTI and extraction string were more likely to develop UTI than those with prior UTI and no extraction string (p = 0.01). There were not enough males with history of UTI to analyze alone. There were 5 (10%) stent dislodgements in the extraction string group, 2 required further intervention with cystoscopy or percutaneous drainage.

DISCUSSION

Extraction strings provide the assurance of drainage while avoiding the need for a second general anesthetic procedure. There is not an increased risk of UTI with extraction string in those without prior history of UTI, but we no longer routinely leave extraction strings if there is history of UTI.

CONCLUSION

Children, particularly females, with prior history of UTI have a significantly increased risk of febrile UTIs associated with the use of extraction strings. Prophylaxis does not seem to reduce this risk. Patients with no prior UTI had no higher risk of UTI with extraction string use for pyeloplasty or UU.

Clinical utility and interrater reliability of video urodynamics in children with isolated fibrolipoma of filum terminale

INTRODUCTION

Children with an isolated fibrolipoma of filum terminale (IFFT) but otherwise normal spinal cord are often evaluated with video urodynamics (VUDS). VUDS interpretation is subjective and can be difficult in young children. These patients may undergo detethering surgery if there is concern for current or future symptomatic tethered cord.

OBJECTIVE

We hypothesized that VUDS in children with IFFT would have limited clinical utility regarding decision for or against detethering surgery and VUDS interpretation would have poor interrater reliability.

METHODS

Patients with IFFT who underwent VUDS for from 2009 to 2021 were retrospectively reviewed to evaluate clinical utility of VUDS. 6 pediatric urologists who were blinded to patient clinical characteristics reviewed the VUDS. Gwet's first order agreement coefficient (AC1) with 95% CI was used to assess interrater reliability.

RESULTS

47 patients (24F:23M) were identified. Median age at initial evaluation was 2.8yrs (IQR:1.5-6.8). 24 (51%) patients underwent detethering surgery (Table). VUDS at initial evaluation were interpreted by treating urologist as normal in 4 (8%), reassuring for normal in 39 (81%), or concerning for abnormal in 4 (9%). Based on neurosurgery clinic and operative notes for the 47 patients, VUDS made no change in management in 37 patients (79%), prompted detethering in 3 (6%), was given as reason for observation in 7 (15%), and was normal or reassuring for normal but not documented as a reason for observation in 16 (34%) (Table). Interrater reliability for VUDS interpretation had fair agreement (AC1 = 0.27) for overall categorization of VUDS and EMG interpretation (AC1 = 0.34). Moderate agreement was seen for detrusor overactivity interpretation (AC1 = 0.54) and bladder neck appearance (AC1 = 0.46).

DISCUSSION

In our cohort, 90% of patients had a normal or reassuring for normal interpretation of VUDS. VUDS interpretation affected clinical course in a minority of patients. There was fair interrater reliability for overall VUDS interpretation and therefore clinical course regarding detethering surgery could vary depending upon interpreting urologist. This fair interrater variability appeared to be related to variability in EMG, bladder neck appearance, and detrusor overactivity interpretation.

CONCLUSION

VUDS affected clinical management in about 20% of our cohort and supported the choice for observation in around 50% of patients. This suggests VUDS does have clinical utility in pediatric patients with IFFT. The overall VUDS interpretation had fair interrater reliability. This suggest VUDS interpretation has limitations in determining normal versus abnormal bladder function in children with IFFT. Neurosurgeons and urologists should be aware of VUDS limitations in this patient population.

Cannabinoid modulation of corticolimbic activation during extinction learning and fear renewal in adults with posttraumatic stress disorder

Failure to successfully extinguish fear is a hallmark of trauma-related disorders, like posttraumatic stress disorder (PTSD). PTSD is also characterized by dysfunctional corticolimbic activation and connectivity. The endocannabinoid system is a putative system to target for rescuing these behavioral and neural deficits. In healthy adults, acute, low-dose delta-9-tetrahydrocannabinol (THC) facilitates fear extinction and increases cortico-limbic activation and connectivity in response to threat. The present study determines the effect of acute, low-dose THC on fear-related brain activation and connectivity during fear extinction in trauma-exposed adults with (PTSD = 19) and without PTSD [trauma-exposed controls (TEC) = 26] and non-trauma-exposed [healthy controls (HC) = 26]. We used a Pavlovian fear conditioning and extinction paradigm, where we measured concurrent functional magnetic resonance imaging (fMRI) and behavioral responses (i.e., skin conductance responding and expectancy ratings). Using a randomized, double-blind, placebo-controlled design, N = 71 subjects were randomized to receive placebo (PBO, n = 37) or THC (n = 34) prior to fear extinction learning. During early extinction learning, individuals with PTSD given THC had greater vmPFC activation than their TEC counterparts. During a test of the return of fear (i.e., renewal), HC and individuals with PTSD given THC had greater vmPFC activation compared to TEC. Individuals with PTSD given THC also had greater amygdala activation compared to those given PBO. We found no effects of trauma group or THC on behavioral fear indices during extinction learning, recall, and fear renewal. These data suggest that low dose, oral THC can affect neural indices of fear learning and memory in adults with trauma-exposure; this may be beneficial for future therapeutic interventions seeking to improve fear extinction learning and memory.

Delayed Surgical Management of an Unusual Classic Bladder Exstrophy Variant

Anterior abdominal wall defects are rare anomalies that can affect multiple organ systems including gastrointestinal, genitourinary, musculoskeletal, and the neurospinal axis. The highly varied, complex anatomy in this patient population creates a challenging reconstruction scenario that merits careful surgical planning. We present an unusual female variant with an anorectal malformation as well as musculoskeletal and genital abnormalities consistent with classic bladder exstrophy in which the urinary bladder, sphincter, and urethra were largely uninvolved.

Is a "Urology Intern Boot Camp" Needed?

INTRODUCTION

The preparation of medical students for internship during medical school is variable, which can negatively affect the performance and confidence of new urology residents year 1. The primary objective is to assess the need for a workshop/curriculum to prepare medical students transitioning to urology residency. Our secondary objective is to identify the appropriate workshop/curriculum design and to identify the needed topics.

METHODS

A survey was developed to evaluate the utility of a Urology Intern Boot Camp for incoming first year urology residents utilizing 2 existing intern boot camp models from other surgical disciplines. Urology Intern Boot Camp content and format and programmatic structure were also considered. The survey was sent to all first- and second-year urology residents and urology residency program directors and chairs.

RESULTS

A total of 730 surveys were sent, including 362 first- and second-year urology residents and 368 program directors/chairs. Responses were received from 63 residents and 80 program directors/chairs for an overall response rate of 20%. Only 9% of urology programs provide a Urology Intern Boot Camp. Interest in participating in Urology Intern Boot Camp was high with 92% of residents interested. Programmatic support for a Urology Intern Boot Camp was also high with 72% of program directors/chairs willing to allow time off and 51% willing to financially support intern participation.

CONCLUSIONS

There is significant interest from urology residents and program directors/chairs in providing incoming urology interns a boot camp. The format of the Urology Intern Boot Camp preferred was a combination of didactics and hands-on skills, and a hybrid delivery model of virtual and in-person carried out in multiple sites around the country.

Perineal groove: Case report

We report the case of a newborn female with a perineal groove and review the limited literature. This is a rare congenital midline malformation of the perineal raphe with no data driven management strategies available. Our patient was managed conservatively with topical Vaseline application. At 52 days of life, her perineal groove was about 50% resolved, and at 9 months of age, it was barely perceptible. She maintained normal urinary function without evidence of infection or discomfort. We recommend this strategy for initial management of perineal grooves that have not had any symptoms or complications attributable to the condition.

Bladder management in children with transverse myelitis

BACKGROUND

Patients with transverse myelitis (TM) often present with urinary retention. While many recover their bladder function, some have persistent voiding dysfunction, and both intermediate and long-term outcomes are variable.

OBJECTIVE

In patients who develop urinary retention requiring clean intermittent catheterization (CIC) at onset of TM, we sought to assess factors associated with improved voiding function and the risk of requiring persistent CIC over time.

STUDY DESIGN

We reviewed children evaluated at our institution for TM from April 1998 to October 2018. Patients were included if they required CIC at initial presentation of TM. Demographics, initial and follow up neurologic exams were evaluated for their association with a return to baseline volitional voiding after requiring catheterization upon diagnosis of TM, with or without medical therapy.

RESULTS

Among the 78 patients who presented with TM during the study period, 43 patients required CIC, with median follow up of 2.7 years. When evaluating for demographic or sensorimotor features associated with improvement to baseline voiding function in patients who initially required CIC, preserved lower extremity reflexes at presentation was the only significant prognostic factor (p < 0.05). Additionally, having complete lower motor neurologic recovery was associated with volitional voiding (p < 0.05). Among the 43 patients who were initially catheterizing, 27/43 (62%) were volitionally voiding at median follow up of 7 months from initial presentation, while the remaining 16/43 remained on CIC for a median follow up of 3.6 years. The cumulative risk of remaining on CIC was 60%, 47%, and 42% at 1, 5, and 10 year follow up, respectively, though there was not a significant difference in the rate of bladder recovery if patients had preserved reflexes.

DISCUSSION

In children with TM who initially developed urinary retention, intact reflexes at presentation were associated with urologic recovery. Additionally, complete neurologic recovery was associated with volitional voiding. While 62% were volitionally voiding at most recent follow-up, the cumulative incidence of dependence on CIC within the first year of diagnosis was 60%, with a relatively few patients regaining volitional voiding by 10 years of follow-up.

CONCLUSION

Among those initially evaluated for urinary retention in the setting of transverse myelitis, intact lower extremity reflexes on physical exam was associated with improved voiding function at most recent follow-up. However, more than half the patients on CIC at initial presentation required CIC at one year of follow-up. Careful, long-term monitoring of voiding status in patients with TM is recommended, even with improvement of neurological status.

Inguinal prolapse of a retroperitoneal lymphovascular malformation

Abdominal lymphovascular malformations (ALMs) are rare cystic masses that can present with nonspecific symptoms. We present a case of a 7-month-old boy who, during an uncomplicated communicating hydrocele repair, was found to have an incidental large, prolapsed mesenteric abdominal lymphovascular malformation. The case serves to highlight the variability in presentation and natural history of ALMs, and the ease with which they can be disguised by more common pathology. We further underscore the importance of individualized therapy with regards to ALMs, emphasized by our course of active surveillance allowing our patient to avoid ionizing radiation and additional surgical intervention.

Meeting report on the NIDDK/AUA Workshop on Congenital Anomalies of External Genitalia: challenges and opportunities for translational research

Congenital anomalies of the external genitalia (CAEG) are a prevalent and serious public health concern with lifelong impacts on the urinary function, sexual health, fertility, tumor development, and psychosocial wellbeing of affected individuals. Complications of treatment are frequent, and data reflecting long-term outcomes in adulthood are limited. To identify a path forward to improve treatments and realize the possibility of preventing CAEG, the National Institute of Diabetes and Digestive and Kidney Diseases and the American Urological Association convened researchers from a range of disciplines to coordinate research efforts to fully understand the different etiologies of these common conditions, subsequent variation in clinical phenotypes, and best practices for long term surgical success. Meeting participants concluded that a central data hub for clinical evaluations, including collection of DNA samples from patients and their parents, and short interviews to determine familial penetrance (small pedigrees), would accelerate research in this field. Such a centralized datahub will advance efforts to develop detailed multi-dimensional phenotyping and will enable access to genome sequence analyses and associated metadata to define the genetic bases for these conditions. Inclusion of tissue samples and integration of clinical studies with basic research using human cells and animal models will advance efforts to identify the developmental mechanisms that are disrupted during development and will add cellular and molecular granularity to phenotyping CAEG. While the discussion focuses heavily on hypospadias, this can be seen as a potential template for other conditions in the realm of CAEG, including cryptorchidism or the exstrophy-epispadias complex. Taken together with long-term clinical follow-up, these data could inform surgical choices and improve likelihood for long-term success.

ACR Appropriateness Criteria® Antenatal Hydronephrosis-Infant

Antenatal hydronephrosis is the most frequent urinary tract anomaly detected on prenatal ultrasonography. It occurs approximately twice as often in males as in females. Most antenatal hydronephrosis is transient with little long-term significance, and few children with antenatal hydronephrosis will have significant obstruction, develop symptoms or complications, and require surgery. Some children will be diagnosed with more serious conditions, such as posterior urethral valves. Early detection of obstructive uropathy is necessary to mitigate the potential morbidity from loss of renal function. Imaging is an integral part of screening, diagnosis, and monitoring of children with antenatal hydronephrosis. Optimal timing and appropriate use of imaging can reduce the incidence of late diagnoses and prevent renal scarring and other complications. In general, follow-up neonatal ultrasound is recommended for all cases of antenatal hydronephrosis, while further imaging, including voiding cystourethrography and nuclear scintigraphy, is recommended for moderate or severe cases, or when renal parenchymal or bladder wall abnormalities are suspected. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Robotic Ureteral Reimplantation

Minimally invasive techniques have gained popularity in pediatric surgery. Among these, is the robotic approach for ureteral reimplantation in children with vesico-ureteral reflux. We describe main indications of this surgery, our surgical technique as well as trouble shooting of anatomical variants and the post-operative management. We also provide a description of other techniques described in the literature and a brief review of outcomes of published series.

The learning curve for robotic-assisted pyeloplasty in children: Our initial experience from a single center

Background:

Robotic-assisted pyeloplasty surgery has become the preferred approach of ureteropelvic junction obstruction (UPJO) in pediatrics. However, to our knowledge, there is limited data on the learning curve for robotic-assisted pyeloplasty in children and no similar study from Saudi Arabia.

Aims:

The objective of the study was to evaluate the progression of the surgical team performing robotic-assisted laparoscopic pyeloplasty (RALP) and to assess the feasibility of the RALP in children, since it is having been recently started in the Kingdom.

Settings and Design:

Retrospective charts and surgical videos review at the tertiary care centre.

Subjects and Methods:

After approval from the internal review board (IRB), we reviewed the surgical video recording of the RALP procedure of 15 patients presented with UPJO from January 2016 to October 2017. Statistical analysis was done for the variables includes dissection time, pyelotomy, anastomosis on both sides, and total surgery time and calculated in minutes. Renal ultrasound reviewed to assess any change in grade.

Results:

Fifteen patients with UPJO underwent RALP. Of 15 cases, nine were primary and six cases as secondary UPJO. The median age was 8 (3–15) years. Out of 15 cases, 13 and 2 patients diagnosed as Society for Fetal Urology grades of 4 and 3, respectively. Total operative time was prolonged in secondary group as compared to primary pyeloplasty group (mean [standard deviation (SD)]: 166.3 [35.1], range: 125–223, P = 0.0028 versus mean (SD): 149.17 (30.4), range: (114–207), P = 0.0008). The success rate was 100% in primary and 84% in secondary cases. The median length of follow-up was 12.0 (7.0–18.0) and 10.0 (8.0–12.5) months in primary and secondary cases, respectively. The overall complication rate was 13% (2/15) (Clavien grade: 1–2).

Conclusions:

The evaluation of the learning curve of RALP for this group of patients concluded that total operative time for RALP, performed by the pediatric urology team, steadily decreased with collective surgical experience.

ACR Appropriateness Criteria® Hematuria-Child

Hematuria is the presence of red blood cells in the urine, either visible to the eye (macroscopic hematuria) or as viewed under the microscope (microscopic hematuria). The clinical evaluation of children and adolescents with any form of hematuria begins with a meticulous history and thorough evaluation of the urine. The need for imaging evaluation depends on the clinical scenario in which hematuria presents, including the suspected etiology. Ultrasound and CT are the most common imaging methods used to assess hematuria in children, although other imaging modalities may be appropriate in certain instances. This review focuses on the following clinical variations of childhood hematuria: isolated hematuria (nonpainful, nontraumatic, and microscopic versus macroscopic), painful hematuria (ie, suspected nephrolithiasis or urolithiasis), and renal trauma with hematuria (microscopic versus macroscopic). The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Robotic excision and ureteroureterostomy of blind-ending ureteral 'Duplication'

INTRODUCTION

Duplicated ureteral anatomy can be a reconstructive challenge. Blind-ending ureteral duplication has been reported with recommendations for surgical excision.

OBJECTIVE

This video reviews the importance of exposure of anatomic landmarks in surgical excision of a blind-ending ureteral duplication.

MATERIALS AND METHODS

This is a retrospective case report of a patient who presented with a blind-ending ureteral duplication.

DISCUSSION

A 13-year-old female presented with a right-sided abdominal mass. Abdominal and pelvic imaging revealed a tubular structure adjacent to and below the right kidney, possibly connecting to the right lower pole. While initially observed, the patient re-presented with urosepsis. A retrograde pyelogram showed no connection between the right ureter and this structure. The patient underwent robotic-assisted excision of this structure. Intra-operatively, it was connected to the right lower pole calyces. A ureteroureterostomy to the orthotopic ureter was performed. Although the structure was adjacent to the bladder dome, there was no communication distally. Postoperatively, the patient did well; follow-up imaging showed a non-dilated lower pole. The pathology of this structure was benign urothelium.

CONCLUSIONS

Surgical management of aberrant ureteral duplications should focus on identifying known landmarks and should be considered to prevent symptomatic infections and renal scarring.

Managing vesicoureteral reflux in children: making sense of all the data

Current management of vesicoureteral reflux (VUR) in children is the result of a steady albeit controversial evolution of data and thinking related to the clinical impact of VUR and urinary tract infection (UTI) in children, the value of clinical screening, and the relative impact of testing and interventions for VUR. While controversy continues, there is consensus on the importance of bladder dysfunction on VUR outcomes, the likelihood of VUR resolution, and the fact that not all children with VUR require active treatment. Early efforts to define risk stratification hold the most promise to provide more patient-specific treatment of UTI and VUR in children.

Robotic Assisted Surgery in Pediatric Urology: Current Status and Future Directions

The evolution of robotic surgical technology and its application in Pediatric Urology have been rapid and essentially successful. Further development remains limited in three key areas: procedural inefficiencies, cost and integration of surgical and clinical information. By addressing these challenges through technology and novel surgical paradigms, the real potential of surgical robotics in pediatric, as well as adult applications, may ultimately be realized. With this evolution, a continued focus on patient-centered outcomes will be essential to provide optimal guidance to technical innovations.

ACR Appropriateness Criteria® Urinary Tract Infection-Child

Urinary tract infection (UTI) is common in young children and may cause pyelonephritis and renal scarring. Long-term complications from renal scarring are low. The role of imaging is to evaluate for underlying urologic abnormalities and guide treatment. In neonates there is increased risk for underlying urologic abnormalities. Evaluation for vesicoureteral reflux (VUR) may be appropriate especially in boys because of higher prevalence of VUR and to exclude posterior urethral valve. In children older than 2 months with first episode of uncomplicated UTI, there is no clear benefit of prophylactic antibiotic. Ultrasound is the only study that is usually appropriate. After the age of 6 years, UTIs are infrequent. There is no need for routine imaging as VUR is less common. In children with recurrent or complicated UTI, in addition to ultrasound, imaging of VUR is usually appropriate. Renal cortical scintigraphy may be appropriate in children with VUR, as renal scarring may support surgical intervention. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Mindfulness and dynamic functional neural connectivity in children and adolescents

BACKGROUND

Interventions that promote mindfulness consistently show salutary effects on cognition and emotional wellbeing in adults, and more recently, in children and adolescents. However, we lack understanding of the neurobiological mechanisms underlying mindfulness in youth that should allow for more judicious application of these interventions in clinical and educational settings.

METHODS

Using multi-echo multi-band fMRI, we examined dynamic (i.e., time-varying) and conventional static resting-state connectivity between core neurocognitive networks (i.e., salience/emotion, default mode, central executive) in 42 children and adolescents (ages 6-17).

RESULTS

We found that trait mindfulness in youth relates to dynamic but not static resting-state connectivity. Specifically, more mindful youth transitioned more between brain states over the course of the scan, spent overall less time in a certain connectivity state, and showed a state-specific reduction in connectivity between salience/emotion and central executive networks. The number of state transitions mediated the link between higher mindfulness and lower anxiety, providing new insights into potential neural mechanisms underlying benefits of mindfulness on psychological health in youth.

CONCLUSIONS

Our results provide new evidence that mindfulness in youth relates to functional neural dynamics and interactions between neurocognitive networks, over time.

Report on The Society for Fetal Urology panel discussion on the selection criteria and intervention for fetal bladder outlet obstruction

INTRODUCTION

The Society for Fetal Urology panel section at the 2016 Fall Congress featured a multidisciplinary discussion on appropriate patient selection, the conservative versus surgical management, and postnatal renal outcome of fetuses with lower urinary tract obstruction (LUTO).

SELECTION CRITERIA FOR INTERVENTION

Rodrigo Ruano shared his experience of prenatal intervention, presenting the outcome of 111 fetuses with severe LUTO treated with vesicoamniotic shunting (VAS) (n = 16), cystoscopy (n = 34) or no intervention (n = 61) in a non-randomized series. Multivariate analysis at the 6-month follow-up suggested a significantly higher probability of survival with fetal intervention versus no intervention. A clear trend for normal renal function was present in the fetal cystoscopy group, but not in the VAS group. In cases in which there was a postnatal diagnosis of posterior urethral valves (n = 57), fetal cystoscopy was effective in improving both the 6-month survival rate and renal function, while VAS was associated with an improvement in the 6-month survival rate. In an attempt to better define which fetuses would benefit from intervention, Michael Braun explained the proposed LUTO classification system that incorporates: (1) fetal urinary biomarkers of renal injury; (2) amniotic fluid levels as a surrogate for the severity of obstruction; and (3) imaging studies to identify signs of renal dysplastic or cystic changes. Intervention was not recommended in patients at low risk of either renal disease or pulmonary hypoplasia (Stage 1). Vesicoamniotic shunting was performed in patients at high risk of either progressive renal injury or pulmonary hypoplasia without evidence of severe pre-existing renal damage (Stage 2). For those patients, who at the time of evaluation had evidence of severe renal disease (Stage 3), fetal intervention was individualized and often based on bladder capacity and bladder refilling after vesicocentesis. He went on to present the nephrologic outcome of fetuses managed over the last 3 years utilizing the selection criteria. Craig Peters supported the concept of selective criteria and discussed the cautious viewpoint, namely: (1) the procedure may be unnecessary, as it is possible for patients to do well, in spite of severe prenatal obstruction; and (2) the risk of giving partial treatment by allowing the baby to survive to delivery with the daunting postnatal journey of renal and pulmonary insufficiency.

CONCLUSION

Standardized patient selection utilizing a staging system is undoubtedly the way forward and will enable comparable long-term renal and bladder functional outcome studies.

Simple visual review of pre- to post-operative renal ultrasound images predicts pyeloplasty success equally as well as geometric measurements: A blinded comparison with a gold standard

BACKGROUND

MAG3 diuretic renal scan remains the gold standard for determination of improvement in renal drainage following pyeloplasty for ureteropelvic junction obstruction. We hypothesized that (i) a change in geometric measurements between pre-operative and post-operative renal ultrasound (RUS) images and (ii) blinded simple visual review of images both would predict pyeloplasty success.

OBJECTIVE

To determine if simple visual review and/or novel geometric measurement of renal ultrasounds can detect pyeloplasty failure.

STUDY DESIGN

This study was a retrospective, blinded comparison with a gold standard. Included were children aged ≤18 years undergoing pyeloplasty at our institution from 2009 to 2015. For each kidney, representative pre-operative and post-operative RUS images were chosen. Our standard for pyeloplasty success was improved drainage curve on MAG3 and lack of additional surgery. Measurements for collecting system circularity, roundness, and renal parenchymal to collecting system area ratio (RPCSR) were obtained by three raters (Figure), who were blinded to the outcome of the pyeloplasty. Changes in geometric measurements were analyzed as a diagnostic test for MAG3-defined pyeloplasty success using ROC curve analysis. In addition, six reviewers blinded to pyeloplasty success reviewed pre-operative and post-operative images visually for improved hydronephrosis and categorized pyeloplasty as success or failure based on simple visual review of RUS.

RESULTS

Fifty-three repaired renal units were identified (50 children). There were five pyeloplasty failures, four of which underwent revision or nephrectomy. While all geometric measurements could discriminate pyeloplasty failure and success, the geometric measurements that discriminated best between pyeloplasty failure and success were change in collecting system roundness and change in RPCSR. Consensus opinion among six blinded reviewers using simple visual review had a sensitivity of 94% and PPV of 100% with respect to identifying pyeloplasty success (AUC 0.97 (95% CI 0.93-1.0)). This was not significantly different from AUC for change in roundness (p = 0.09) or change in RPCSR (p = 0.1).

DISCUSSION

Change in collecting system roundness and change in RPCSR were the most accurate geometric measurements in predicting pyeloplasty success. Simple visual review of ultrasound images for pyeloplasty success performed as well or better than geometric measurements. However, geometric measurements remain useful as a research tool or to communicate findings between clinicians.

CONCLUSIONS

Complex geometric measurements of hydronephrosis or post-operative MAG3 scans are not needed if hydronephrosis is visually significantly improved, as simple visual review is highly sensitive for detecting pyeloplasty failure.

Congenital infundibulopelvic stenosis: Indications for intervention, surgical technique, and review of literature

INTRODUCTION

Congenital infundibulopelvic stenosis (IFPS) is a rare renal dysmorphism marked by dilated calyces proximal to diminutive infundibulum and renal pelvises. The entity is theorized to exist on the spectrum of congenital obstructive renal diseases between ureteropelvic junction obstruction and multicystic dysplasia.

OBJECTIVE

This case series sought to review and present the surgical management of three cases of IFPS with progressive renal insufficiency.

MATERIALS AND METHODS

After Institute Review Board approval, we reviewed three cases of IFPS treated by a single surgeon over a 20-year period. All cases displayed evidence of progressive renal decline. The first case of a 16-year-old female had IFPS in a solitary kidney, with previous contralateral nephrectomy of a multicystic dysplastic kidney. The second case, a 17-year-old male, presented after blunt trauma to the ipsilateral flank. The third case of a 10-year-old female presented with microhematuria, mild azotemia and bilateral IFPS.

RESULTS

Our current surgical management has evolved from renal sinus exposure and multiple infundibuloplasties in the first case to preoperative three-dimensional mapping of the dilated calyceal system with intraoperative ultrasonography for selective calicocalicostomies draining to a lower pole ureterocalicostomy in the third case. Our first case, treated with multiple infundibuloplasties experienced slow renal decline into her 20s, and the later cases, treated with calicocalicostomies, have experienced stable to mild loss of renal function with ongoing nephrological follow-up.

DISCUSSION

IFPS is a complex pediatric urology problem without a clear treatment algorithm. The goal of surgical intervention is to offer an opportunity to halt or reduce progressive renal insufficiency. Our current surgical approach utilizes preoperative three-dimensional modeling via magnetic resonance urography to guide placement of multiple calicocalicostomies draining to a lower pole ureterocalicostomy.

CONCLUSIONS

Not all cases of IFPS require surgical intervention. We have intervened in cases of IFPS with progressive hydronephrosis or worsening renal insufficiency with acceptable results.

Reoperative robotic pyeloplasty in children

INTRODUCTION

Reoperative pyeloplasty for recurrent ureteropelvic junction obstruction (UPJO) can be technically challenging and is associated with greater morbidity and lower success rates than an initial repair. Robotic-assisted laparoscopic pyeloplasty (RALP) previously has been demonstrated to be a safe and effective approach for management of recurrent UPJO; however, the length of follow-up has been limited. The objective of this study was to confirm the safety and efficacy of RALP for UPJO in children following failed previous pyeloplasty and provide clinical benchmarks for intermediate length follow-up in this patient population.

METHODS

An IRB approved retrospective chart review was performed for all patients undergoing reoperative RALP from June 2006 to December 2014. All cases were performed by surgeons from two institutions for persistent UPJO following failed initial pyeloplasty. Information including demographic information, radiographic studies, and operative interventions performed between the initial repair and reoperative surgery, reoperative RALP intraoperative data, postoperative clinical course and imaging studies, and subsequent interventions following reoperative RALP were extracted.

RESULTS

Twenty-three children underwent reoperative RALP. Eleven patients had right- and 12 left-sided repairs. Median age at reoperative RALP was 4.0 years and median interval between surgeries was 1.3 years. Indications for repeat repair included pain, infection, and/or radiographic evidence of worsening obstruction and/or deteriorating renal function. Mean operative time was 198 min from incision to port closure. Mean length of stay was 2.3 days. Six complications occurred in five patients within 30 days postoperatively, including ileus, pneumonia, and urinary tract infection. Median length of follow-up was 26 months (range 4-45 months) for all patients and 31 months (range 16-45 months) in 18 patients with >12 months of follow-up. More than 80% of patients presenting with flank pain prior to reoperative RALP had resolution of this symptom. To date, 78% of patients with >12 months of follow-up have not required further operative intervention. Excellent results have been achieved in 14 of 18 patients (78%) with sufficient postoperative follow-up in terms of length of follow-up (>12 months), symptom resolution, and/or improved imaging results.

CONCLUSIONS

RALP following previous pyeloplasty is technically feasible with acceptable operative times, lengths of stay, and complication rates. Reoperative RALP is our preferred modality for repair of recurrent UPJO with the vast majority of patients having successful outcomes based on imaging, resolution of symptoms, and the rare need for further intervention across an intermediate length follow-up period.

Renal Segmentation From 3D Ultrasound via Fuzzy Appearance Models and Patient-Specific Alpha Shapes

Ultrasound (US) imaging is the primary imaging modality for pediatric hydronephrosis, which manifests as the dilation of the renal collecting system (CS). In this paper, we present a new framework for the segmentation of renal structures, kidney and CS, from 3DUS scans. First, the kidney is segmented using an active shape model-based approach, tailored to deal with the challenges raised by US images. A weighted statistical shape model allows to compensate the image variation with the propagation direction of the US wavefront. The model is completed with a new fuzzy appearance model and a multi-scale omnidirectional Gabor-based appearance descriptor. Next, the CS is segmented using an active contour formulation, which combines contour- and intensity-based terms. The new positive alpha detector presented here allows to control the propagation process by means of a patient-specific stopping function created from the bands of adipose tissue within the kidney. The performance of the new segmentation approach was evaluated on a dataset of 39 cases, showing an average Dice's coefficient of 0.86±0.05 for the kidney, and 0.74 ± 0.10 for the CS segmentation, respectively. These promising results demonstrate the potential utility of this framework for the US-based assessment of the severity of pediatric hydronephrosis.

Quantification of kidneys from 3D ultrasound in pediatric hydronephrosis

This paper introduces a complete framework for the quantification of renal structures (parenchyma, and collecting system) in 3D ultrasound (US) images. First, the segmentation of the kidney is performed using Gabor-based appearance models (GAM), a variant of the popular active shape models, properly tailored to the imaging physics of US image data. The framework also includes a new graph-cut based method for the segmentation of the collecting system, including brightness and contrast normalization, and positional prior information. The significant advantage (p = 0.03) of the new method over previous approaches in terms of segmentation accuracy has been successfully verified on clinical 3DUS data from pediatric cases with hydronephrosis. The promising results obtained in the estimation of the volumetric hydronephrosis index demonstrate the potential of our new framework to quantify anatomy in US and asses the severity of hydronephrosis.

Neonatal and early infancy management of prenatally detected hydronephrosis

Hydronephrosis discovered during prenatal ultrasound will often resolve spontaneously; however, it should be evaluated in the postnatal period in a manner commensurate with its risk of renal injury. Early intervention is appropriate in cases of bladder outlet obstruction or the severely obstructed solitary kidney. In most other cases, it is both safe and reasonable to allow the possibility of spontaneous improvement with the intensity of follow-up based on the severity of the hydronephrosis. Clinical decision making should be a shared process between families and caregivers.

Bi-Institutional Comparison of Robot-Assisted Laparoscopic Versus Open Ureteroureterostomy in the Pediatric Population

PURPOSE

Ureteroureterostomy (UU) is a useful surgical option for the management of duplication anomalies as well as obstructed single system ureters for children. We aimed to evaluate the safety, efficacy, and outcomes of robot-assisted laparoscopic UU (RALUU) compared with open UU (OUU) in the pediatric population.

PATIENTS AND METHODS

A retrospective review was performed at two institutions including six surgeons' experience with all cases of RALUU and OUU from January 2005 to June 2014. Indications for a surgical procedure included duplex systems with an upper pole ectopic ureter, obstructed ureterocele or lower pole vesicoureteral reflux, and obstruction in a single system. Transureteroureterostomy, laparoscopic UU, and major reconstruction cases where UU was the secondary procedure were excluded.

RESULTS

There were 25 RALUU and 19 OUU cases included. All cases involved duplex systems except two proximal to distal anastomoses in single system obstructed kidneys. RALUUs were more likely to be performed proximally (P = 0.01) and with the use of cystoscopy and stent placement (P = <0.0001). Operative times and estimated blood loss were similar between the two groups. Postoperative complications included four febrile urinary tract infections in each group, one recurrence of nonfebrile urinary tract infection in the open group, and one postoperative obstruction at the ureterovesical junction because of attempted stent placement necessitating nephrostomy tube placement in the open group. This OUU patient was the only one to demonstrate more severe hydronephrosis after surgery on initial follow-up imaging that was again unrelated to the open UU procedure. RALUU had shorter hospital stays by 0.5 days (P = 0.04).

CONCLUSION

Robot-assisted laparoscopic UU is a safe and effective alternative to open UU in children with duplication anomalies and single system obstructed ureters. Operative times and complication rates were comparable with slightly shorter length of hospitalization in robotic cases.

Antibiotic prophylaxis and reflux: critical review and assessment

The use of continuous antibiotic prophylaxis (CAP) was critical in the evolution of vesicoureteral reflux (VUR) from a condition in which surgery was the standard of treatment to its becoming a medically managed condition. The efficacy of antibiotic prophylaxis in the management of VUR has been challenged in recent years, and significant confusion exists as to its clinical value. This review summarizes the critical factors in the history, use, and investigation of antibiotic prophylaxis in VUR. This review provides suggestions for assessing the potential clinical utility of prophylaxis.

Do Not Judge a Kidney by Its Pelvis: A Rare Case of an Unobstructed Dilated Renal Pelvis

We present a rare case of an unobstructed dilated renal pelvis in a newborn female. Prenatal imaging documented a large abdominal cyst in a stable fetus. Postnatal imaging confirmed persistence of this large cyst but with an unclear etiology. The child was taken to surgery by the pediatric surgeons with concern for a possible harmful nonurologic diagnosis. Intraoperative findings were that of a severely dilated renal pelvis; however, in the absence of an expected ureteropelvic junction obstruction. Reduction pyeloplasty without interference of the ureteropelvic junction proved successful.

Stereoscopic augmented reality for laparoscopic surgery

BACKGROUND

Conventional laparoscopes provide a flat representation of the three-dimensional (3D) operating field and are incapable of visualizing internal structures located beneath visible organ surfaces. Computed tomography (CT) and magnetic resonance (MR) images are difficult to fuse in real time with laparoscopic views due to the deformable nature of soft-tissue organs. Utilizing emerging camera technology, we have developed a real-time stereoscopic augmented-reality (AR) system for laparoscopic surgery by merging live laparoscopic ultrasound (LUS) with stereoscopic video. The system creates two new visual cues: (1) perception of true depth with improved understanding of 3D spatial relationships among anatomical structures, and (2) visualization of critical internal structures along with a more comprehensive visualization of the operating field.

METHODS

The stereoscopic AR system has been designed for near-term clinical translation with seamless integration into the existing surgical workflow. It is composed of a stereoscopic vision system, a LUS system, and an optical tracker. Specialized software processes streams of imaging data from the tracked devices and registers those in real time. The resulting two ultrasound-augmented video streams (one for the left and one for the right eye) give a live stereoscopic AR view of the operating field. The team conducted a series of stereoscopic AR interrogations of the liver, gallbladder, biliary tree, and kidneys in two swine.

RESULTS

The preclinical studies demonstrated the feasibility of the stereoscopic AR system during in vivo procedures. Major internal structures could be easily identified. The system exhibited unobservable latency with acceptable image-to-video registration accuracy.

CONCLUSIONS

We presented the first in vivo use of a complete system with stereoscopic AR visualization capability. This new capability introduces new visual cues and enhances visualization of the surgical anatomy. The system shows promise to improve the precision and expand the capacity of minimally invasive laparoscopic surgeries.

Robot-assisted and laparoscopic repair of ureteropelvic junction obstruction: a systematic review and meta-analysis

CONTEXT

Over the last two decades, minimally invasive treatment options for ureteropelvic junction obstruction (UPJO) have been developed and popularized.

OBJECTIVE

To critically analyze the current status of laparoscopic and robotic repair of UPJO.

EVIDENCE ACQUISITION

A systematic literature review was performed in November 2012 using PubMed. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta-analyses criteria.

EVIDENCE SYNTHESIS

Multiple series of laparoscopic pyeloplasty have demonstrated high success rates and low perioperative morbidity in pediatric and adult populations, with both the transperitoneal and retroperitoneal approaches. Data on pediatric robot-assisted pyeloplasty are increasingly becoming available. A larger number of cases have also been reported for adult patients, confirming that robotic pyeloplasty represents a viable option for either primary or secondary repair. Robot-assisted redo pyeloplasty has been mostly described in the pediatric population. Different technical variations have been implemented with the aim of tailoring the procedure to each specific case. The type of stenting, retrograde versus antegrade, continues to be debated. Internal-external stenting as well as a stentless approach have been used, especially in the pediatric population. Comparative studies demonstrate similar success and complication rates between minimally invasive and open pyeloplasty in both the adult and pediatric setting. A clear advantage in terms of hospital stay for minimally invasive over open pyeloplasty was observed only in the adult population.

CONCLUSIONS

Laparoscopy represents an efficient and effective less invasive alternative to open pyeloplasty. Robotic pyeloplasty is likely to emerge as the new minimally invasive standard of care whenever robotic technology is available because its precise suturing and shorter learning curve represent unique attractive features. For both laparoscopy and robotics, the technique can be tailored to the specific case according to intraoperative findings and personal surgical experience.

Transurethral placement of vaginal contraceptive device in a patient with neurogenic bladder: a case report and review of the literature

BACKGROUND

The NuvaRing is a vaginal contraceptive device that is placed and later removed by the user herself. Incorrect placement is a possible complication and seems an increased risk in patients with spinal cord abnormalities.

CASE

A 21-year-old female with a history of a T7-8 level spinal cord injury at birth and subsequent neurogenic bladder dysfunction and bladder augmentation presented with an 8 month history of suprapubic pain, right hip pain and urgency unresponsive to antibiotic therapy. Her symptoms began after her caretaker placed a NuvaRing contraceptive device, which subsequently was unable to be located. A thorough evaluation revealed a NuvaRing in the bladder.

CONCLUSION

Foreign objects should be considered in patients with recurrent symptoms of cystitis which are unrelieved by antibiotic therapy. Intravaginal contraceptive rings should be used cautiously in patients with spinal cord abnormalities who require the assistance of caretakers for management of these devices.

Changes in the pore network structure of Hanford sediment after reaction with caustic tank wastes

At the former nuclear weapon production site in Hanford, WA, caustic radioactive tank waste leaks into subsurface sediments and causes dissolution of quartz and aluminosilicate minerals, and precipitation of sodalite and cancrinite. This work examines changes in pore structure due to these reactions in a previously-conducted column experiment. The column was sectioned and 2D images of the pore space were generated using backscattered electron microscopy and energy dispersive X-ray spectroscopy. A pre-precipitation scenario was created by digitally removing mineral matter identified as secondary precipitates. Porosity, determined by segmenting the images to distinguish pore space from mineral matter, was up to 0.11 less after reaction. Erosion-dilation analysis was used to compute pore and throat size distributions. Images with precipitation had more small and fewer large pores. Precipitation decreased throat sizes and the abundance of large throats. These findings agree with previous findings based on 3D X-ray CMT imaging, observing decreased porosity, clogging of small throats, and little change in large throats. However, 2D imaging found an increase in small pores, mainly in intragranular regions or below the resolution of the 3D images. Also, an increase in large pores observed via 3D imaging was not observed in the 2D analysis. Changes in flow conducting throats that are the key permeability-controlling features were observed in both methods.

Clinical practice: surgical approaches to urolithiasis in children

The incidence of urolithiasis in children is increasing. Adequate knowledge of treatment modalities and surgical options is therefore essential for every pediatrician. Surgical approaches to urolithiasis in children continue to evolve with advancements in technology and sophistication of current equipment and techniques. Perhaps the most significant development in new techniques is the advent of robotic-assisted laparoscopy. This review, for the general pediatrician, summarizes the most recent pediatric data and guidelines for surgical approaches to treatment of urolithiasis.