Contemporary disparities in progression to orchiopexy for cryptorchidism as reported in the Pediatric Health Information System (PHIS) database

INTRODUCTION

When evaluating the timeliness of orchiopexy for cryptorchidism, health disparities are apparent among Hispanic and African American males and those with public insurance. Since the publication of these data, the COVID-19 pandemic has stressed our healthcare system and significantly affected the provision of pediatric urology care.

OBJECTIVE

We sought to assess if certain groups were disproportionately affected in progression to orchiopexy after the diagnosis of cryptorchidism during and after the pandemic in US freestanding children's hospitals.

STUDY DESIGN

Using the PHIS database, pediatric patients ≤5 years who underwent orchiopexy between January 2018 and December 2022 were retrospectively analyzed. Exclusion criteria included prematurity, retractile testes, and testicular torsion. Primary outcomes were age at orchiopexy and the proportion of individuals undergoing timely orchiopexy for cryptorchidism.

RESULTS

Over the study period 3140 patients ≤5 years old underwent orchiopexy for cryptorchidism. Non-Hispanic Blacks and Hispanics were significantly less likely to have timely orchiopexy and underwent orchiopexy 2.13 and 3.60 months later compared to whites (p < 0.01). As compared to pre-COVID-19, during the pandemic the proportion of patients who had timely surgery was higher and the median age was significantly lower (p = 0.01 and p < 0.01, respectively) in white patients only. Over the study period, patients with public insurance were less likely to have timely orchiopexy and underwent orchiopexy 2.94 months later (p < 0.01) than patients with private insurance. Compared to during the pandemic, post-pandemic a significantly lower proportion of publicly insured patients have since undergone timely orchiopexy (p = 0.04). Patients in the West were less likely to have timely orchiopexy and had a higher age at time of orchiopexy (p < 0.01) than other regions. However, in the West during the pandemic, the proportion of children who had timely surgery was higher compared to pre-and post-COVID-19 (p < 0.01).

DISCUSSION

Overall, regardless of insurance status, race, or location, a significant proportion of patients did not undergo timely orchiopexy. During the pandemic white patients had a lower median age and an increased proportion underwent timely orchiopexy, despite the number of orchiopexies remaining constant. Disparities in the post-COVID-19 era have been further exacerbated for publicly insured patients, who a significantly lower proportion of have since undergone timely orchiopexy. Specific efforts are required across the United States to increase timely orchiopexy for all boys.

CONCLUSIONS

Progression to timely orchiopexy remains low for all boys in the era surrounding COVID-19; certain groups appear to be more adversely affected.

Gonadal tumors in a contemporary cohort of patients with differences in sex development undergoing surgery - A multi-site study from the Pediatric Urologic Oncology Working Group of the societies for pediatric urology

BACKGROUND

Disturbances in gonadal development lead to increased risk of gonadal malignancy in some but not all patients with differences in sex development (DSD). However, the natural history of these tumors is poorly described, and the literature remains sparse.

OBJECTIVE

The objective of this study was to describe the incidence of germ cell neoplasia in situ (GCNIS) and germ cell tumor (GCT) in a contemporary cohort of patients with DSD undergoing surgery and to provide long-term oncologic outcomes for these patients.

STUDY DESIGN

Patients with DSD who have undergone gonadectomy or gonadal biopsy were identified at four institutions. Clinical characteristics, pathology, and treatment details were obtained retrospectively. Patients were stratified into risk categories based on DSD diagnosis. Oncologic treatment and outcomes were recorded. Descriptive statistics are reported using parametric methods.

RESULTS

83 patients were identified. Distribution of diagnoses is summarized in the summary table. 14 (16.9%) patients underwent gonadal biopsy, and 71 (85.5%) patients underwent gonadectomy (50/71 gonadectomies were bilateral). 8/83 (9.6%) patients had GCNIS or GCT (7 GCNIS, 1 GCT). Median age at surgery was 2.95 years (y) (interquartile range [IQR] 0.6-12.2) and 14y (IQR 0.85-16.9) in patients without and with GCNIS/GCT, respectively. All 8 patients with GCNIS/GCT had high or intermediate risk DSD diagnoses (4 mixed gonadal dysgenesis, 3 Turner with Y, 1 partial gonadal dysgenesis). Of the patients with high-risk diagnoses, 8/54 (15%) had GCNIS/GCT. No patient received adjuvant therapy, no patient had a recurrence, and all patients were living with mean follow up 6.4y.

DISCUSSION

The risk of gonadal malignancy is heterogeneous in the DSD population and can vary based on DSD diagnosis as well as maturation, testicularization, and location of the gonads. The most recent consensus recommendations on gonadal management emphasize risk stratification and consideration of gonadal surveillance based on gender of rearing, but supporting literature remains sparse. In this contemporary cohort of DSD patients who underwent gonadal surgery, most patients did not have evidence of adverse pathology, all patients with malignant or premalignant pathology had a high/intermediate risk DSD diagnosis, and all patients with GCNIS/GCT were treated with surgery alone without recurrence.

CONCLUSIONS

The distribution of patients with premalignant and malignant gonadal pathology and DSD in this cohort aligns with prior literature, and oncologic outcomes were excellent. These data add valuable information to the current literature and highlight the necessity to develop appropriate screening regimens for retained gonads.

Current practice in robotic surgery among pediatric urologists: A survey study

INTRODUCTION

Since its introduction, robotic surgery has gained most traction among urologists. Pediatric urologists have been slower to adopt the technology compared to their adult counterparts. Our objectives were to understand current practice patterns for robotic surgery among pediatric urologists, to identify perceived barriers, and to identify factors associated with the use of robotic surgery.

METHODS

An anonymous online survey was administered using REDCap to members of the Societies for Pediatric Urology (SPU) including questions about provider demographics and personal practice patterns. Comparisons were made using Pearson's Chi-Squared analysis.

RESULTS

Of 351 SPU members surveyed, 95 completed the survey (27%). Fifty-five (58%) reported performing robotic surgery, 40 (42%) reported not performing robotic surgery. Twenty-seven (28%) reported receiving robotic training in residency, 26 (27%) in fellowship, 34 (36%) in a robotics course, and 30 (32%) with proctored surgery. Cited reasons for not performing robotic surgery were lack of training, referring to practice partners, and lack of benefit. Of those performing robotic surgery, most reported performing 0-1 or 2-4 per month. Thirty-one (56%) reported having selection criteria for use of the robot: 26 (47%) cited an age cut-off, 12 (22%) a weight cut-off, and 14 (26%) an abdominal size cut-off. Eighteen (33%) reported using hidden incisions endoscopic surgery (HIdES) approach, and 40 (42%) reported using an assistant port. Factors associated with using the robot included surgeon age, years in practice, practice setting, having robotic training, and having practice partners who perform robotic surgery.

CONCLUSIONS

Practice variation exists in the use and application of robotic surgery among pediatric urologists. The main self-reported barriers to performing robotic surgery are lack of training, referring to practice partners, and no perceived benefit to robotic surgery. Factors associated with performing robotic surgery were surgeon age, years in practice, practice setting, and having practice partners perform robotic surgery.

A novel urinary biomarker protein panel to identify children with ureteropelvic junction obstruction - A pilot study

INTRODUCTION AND OBJECTIVE

Reliable urinary biomarker proteins would be invaluable in identifying children with ureteropelvic junction obstruction (UPJO) as the existing biomarker proteins are inconsistent in their predictive ability. Therefore, the aim of this study was to identify consistent and reliable urinary biomarker proteins in children with UPJO.

METHODS

To identify candidate biomarker proteins, total protein from age-restricted (<2 years) and sex-matched (males) control (n = 22) and UPJO (n = 21) urine samples was analyzed by mass spectrometry. Proteins that were preferentially identified in UPJO samples were selected (2-step process) and ranked according to their diagnostic odds ratio value. The top ten proteins with highest odds ratio values were selected and tested individually by ELISA. The total amount of each protein was normalized to urine creatinine and the median with interquartile ranges for control and UPJO samples was determined. Additionally, fold change (UPJO/Control) of medians of the final panel of 5 proteins was also determined. Finally, we calculated the average + 3(SD) and average + 4(SD) values of each of the 5 proteins in the control samples and used it as an arbitrary cutoff to classify individual control and UPJO samples.

RESULTS

In the first step of our selection process, we identified 171 proteins in UPJO samples that were not detected in the majority of the control samples (16/22 samples, or 72.7%). Of the 171 proteins, only 50 proteins were detected in at least 11/21 (52.4%) of the UPJO samples and hence were selected in the second step. Subsequently, these 50 proteins were ranked according to the odds ratio value and the top 10 ranked proteins were validated by ELISA. Five of the 10 proteins - prostaglandin-reductase-1, ficolin-2, nicotinate-nucleotide pyrophosphorylase [carboxylating], immunoglobulin superfamily-containing leucine-rich-repeat-protein and vascular cell adhesion molecule-1 were present at higher levels in the UPJO samples (fold-change of the median protein concentrations ranging from 2.9 to 9.4) and emerged as a panel of biomarkers to identify obstructive uropathy. Finally, the order of prevalence of the 5 proteins in UPJO samples is PTGR1>FCN2>QPRT>ISLR>VCAM1.

CONCLUSION

In summary, this unique screening strategy led to the identification of previously unknown biomarker proteins that when screened collectively, may reliably distinguish between obstructed vs. non-obstructed infants and may prove useful in identifying informative biomarker panels for biological samples from many diseases.

Presentation and Diagnosis of Ureteral Quadruplication: Case Report and Analysis of the Literature

Ureteral quadruplication is exceedingly rare. All except for 2 cases were symptomatic and nearly all underwent intervention. We present the first case of asymptomatic ureteral quadruplication in the presence of ureteral cyst. The report is first to prove ureteral quadruplication, even with ureteral cyst, can have normal renal function and parenchyma without obstruction or reflux. The report analyzes differences between the 14 cases of ureteral quadruplication in the English literature. It is first to describe bilateral ureteral cysts with ureteral quadruplication and triplication, and is first to accurately characterize the appearance of quadruplicated ureters inside the kidney.

Local Control of Perineal Rhabdomyosarcoma: Are Current Recommendations Adequate?

Rhabdomyosarcoma (RMS) is a rare malignancy that can develop in nearly any soft-tissue of the body. Location of the primary tumor affects treatment strategy and prognosis, and RMS of the perineal areas can be especially difficult to treat successfully. RMS is treated systemically with chemotherapy. Local control options include surgical excision, radiation treatment, or a combination of the 2. Treating RMS with radiation treatment can be challenging due to the absence of standardized dosage protocols, along with the presence of conflicting recommendations in the literature. Each case of perineal RMS may benefit from a more individualized treatment plan.

Epispadias repair with tunica vaginalis flap

INTRODUCTION

Primary epispadias is a rare congenital malformation that afflicts about 1 in 80,000 children. The surgical repair, originally described by Cantwell over 100 years ago, is fundamentally sound and incorporates several important steps to achieve an optimal result.

METHODS

A 9-month-old male with penopubic epispadias presented for surgical repair. Pre-operative imaging included a normal renal ultrasound and voiding cystourethrogram that demonstrated a moderate-sized bladder, partially competent bladder neck, and no vesicoureteral reflux. A modified Cantwell-Ransley approach to the repair was performed without complete disassembly of the penis. Established surgical principles of identification of laterally placed neurovascular bundles, preservation of the ventral mesentery to the urethral plate, mobilization of the urethral plate off the corporal bodies with ventral relocation, and dorsal medial rotation of the corporal bodies are demonstrated in this video.

RESULTS

This procedure was performed as an outpatient. The patient had an unremarkable postoperative course. The #6-French urethral stent was removed on postoperative day 10.

CONCLUSIONS

This video demonstrates a modified Cantwell-Ransley technique for epispadias repair, which employs a tunica vaginalis flap to reinforce the urethral repair. The adherence to surgical principles described by Cantwell in the late 1800s for children with primary epispadias continues to lead optimal surgical outcomes.

Objective pain assessment after ureteral reimplantation: comparison of open versus robotic approach

INTRODUCTION

While open ureteral reimplantation is the gold standard of surgical intervention for vesicoureteral reflux (VUR), minimally invasive approaches offer the potential benefits of decreased postoperative pain, improved cosmesis, and shorter hospital stay and convalescence. Studies comparing open and minimally invasive surgery with respect to postoperative pain in children have been inconclusive.

OBJECTIVE

We sought to compare postoperative pain in children undergoing open versus robotic ureteral reimplantation by using age-appropriate, validated pain assessment scales.

METHODS

A prospective cohort of all patients enrolled in an Institutional Review Board-approved VUR surgery registry between July 2010 and February 2013 was analyzed. Patients who underwent endoscopic treatment or who received caudal or epidural anesthesia were excluded. Age-appropriate, validated pain scales ranging from 0 to 10 were utilized for pain assessment. Pain scores and narcotic doses administered on the first postoperative day were analyzed.

RESULTS

Of the 34 subjects included, 11 underwent open intravesical reimplantation, while 23 patients underwent robotic extravesical reimplantation. Table 1 displays patient characteristics and results of pain assessment. Robotic surgery was associated with lower narcotic requirement compared to open surgery (P < 0.05). The difference in pain scores between the two cohorts approached, but did not reach, statistical significance (P = 0.12). However, the percentage of patients with mild or no pain (57% robotic, 27% open) versus severe pain (9% robotic, 45% open) was notably different between the two cohorts.

DISCUSSION

Previous studies addressing the effect of surgical modality on pediatric postoperative pain are limited by their reliance on narcotic administration as an indirect surrogate for measuring pain. In the present study, postoperative pain was assessed with narcotic requirements and consistently collected validated pain scores, which more accurately reflect a patient's perceived pain. Although there was no significant difference in subjective pain scores between patients undergoing open versus robotic reimplantation, the percentage of patients with mild or no pain (57% robotic, 27% open) versus severe pain (9% robotic, 45% open) was notably different between the two cohorts. This study was limited by a lack of randomization as well as small sample size, which did not allow for age sub-group analysis or small differences to be statistically significant.

CONCLUSIONS

In the present study, robotic ureteral reimplantation was associated with lower narcotic requirement compared to open surgery, and lower intensity of postoperative pain according to a direct pain assessment tool. Larger sample sizes are necessary to strengthen statistical comparisons.

Oncology: the role of partial nephrectomy in Wilms tumor

Wilms tumor represents the most common pediatric renal malignancy and the fourth most common childhood cancer overall. Overall survival from Wilms tumor has increased to over 90 % secondary to multidisciplinary therapy and multi-institutional cooperative group trials. Recent therapeutic focus has shifted to reduction in treatment morbidity and renal preservation while maintaining the high survival rates. Partial nephrectomy is an integral component of the multimodal treatment protocols for Wilms tumor patients with bilateral disease, solitary kidney, or predisposing syndromes. Recent consideration has been given to utilization of nephron sparing surgery (NSS) in carefully selected patients with nonsyndromic unilateral Wilms tumor. While long-term, prospective data in this subgroup of patients is not yet available, case series demonstrate comparable oncologic outcomes after partial versus radical nephrectomy. The relative rarity of Wilms tumor, especially those amenable to upfront partial nephrectomy, presents a challenge to conducting controlled trials.

Fetal hydronephrosis as a predictor of neonatal urologic outcomes

OBJECTIVES

The ability to predict surgically relevant fetal renal hydronephrosis is limited. We sought to determine the most efficacious second- and third-trimester fetal renal pelvis anteroposterior diameter cutoffs to predict the need for postnatal surgery.

METHODS

We retrospectively reviewed the medical records of mothers and neonates who had a prenatal sonographic examination in our Perinatal-Pediatric Urology Clinic and received follow-up care. Hydronephrosis was defined as a renal pelvis anteroposterior diameter of 5 mm or greater in the second trimester and 7 mm or greater in the third trimester. Hydronephrosis was subdivided into mild, moderate, and severe.

RESULTS

Of 8453 fetuses, 96 met the criteria and were referred to our clinic. Isolated hydronephrosis was diagnosed in 74 fetuses, of which 53 received postnatal follow-up evaluations. The areas under the receiver operating characteristic curves for predicting postnatal surgery in the second and third trimesters were 0.770 and 0.899, respectively. The second-trimester renal anteroposterior diameter threshold that best predicted post-natal surgery was 9.5 mm (sensitivity, 71.4%; specificity, 81.1%). The third-trimester threshold that best predicted postnatal surgery was 15.0 mm (sensitivity, 85.7%; specificity, 94.6%).

CONCLUSIONS

The fetal renal anteroposterior diameter on second- and third-trimester sonography is predictive of an increased risk for neonatal urologic surgery. Surgical risk is best predicted by a third-trimester renal anteroposterior diameter threshold of 15 mm.

Primary renal synovial sarcoma in a 13-year-old boy

Primary renal synovial sarcoma is a rare entity with fewer than 40 cases reported in the literature. Its clinical presentation and radiographic features, namely, its often complex cystic appearance, make it difficult to differentiate from other benign or malignant renal lesions. Although there are certain consistent morphological and immunohistochemical features, diagnosis ultimately depends on molecular studies. Prognosis is poor, and there currently exists no defined treatment protocol. Herein, we describe the youngest reported case of primary renal synovial sarcoma in the literature.

Pediatric urologic oncology: organ-sparing surgery in kidney and testis

Technological advances in imaging as well as increased knowledge of tumor-specific biology have promoted the role of organ-sparing approaches to pediatric renal and testicular tumors. Application of these techniques continues to evolve as data on long-term follow-up become available and as protocol-guided investigation provides answers to therapeutic outcomes of these approaches. Optimally, organ-sparing surgery will continue to provide increased potential for preservation of both renal function and fertility.

Infant communicating hydroceles--do they need immediate repair or might some clinically resolve?

PURPOSE

Infant hydroceles that are communicating by history (fluctuation in size) or examination (reducible fluid) are often repaired soon after presentation. We have followed a series of infant boys with such hydroceles and reviewed their early natural history.

MATERIALS AND METHODS

Since 1998, we have followed 174 infant boys presenting with an apparent communicating hydrocele without immediate surgical repair. All boys were initially seen before 18 months of age and most (168) by 12 months. Most had been full term at delivery, although 32 had been premature (<37 weeks' gestational age) and 11 extremely so (<32 weeks). Most boys (120) had bilateral hydroceles at presentation.

RESULTS

Of the 110 boys followed to disposition, 69 (62.7%) had complete resolution without surgery by a mean age of 11.7 months. Forty-one patients (37.3%) underwent surgery for correction at a mean age of 14 months because of persistence in size or development of a hernia. Six developed a hernia during observation, none of whom had any episode of incarceration. Only 2 patients with apparent resolution subsequently had recurrence with a hernia. Age at presentation and gestational age at birth showed no effect on resolution. The hydroceles of 64 boys had improved in size after a mean follow-up of 13.9 months when last seen.

CONCLUSIONS

Many infant hydroceles that are communicating by history or examination do resolve clinically without surgery and deserve observation. Progression to hernia was rare in our experience and did not result in incarceration. Consequently, little risk is taken by initial observation.

Recruitment of bone marrow derived cells to the bladder after bladder outlet obstruction

PURPOSE

Bladder fibrosis is an undesired end point of partial bladder outlet obstruction. In fibrotic disease of the lung, kidney, skin and heart chemokines recruit bone marrow derived cells to injured tissue. Blockade of chemokines like CCL2 results in decreased fibrosis in other organs. To our knowledge we present the first report of bone marrow derived cell recruitment to the bladder in a murine bladder outlet obstruction model.

MATERIALS AND METHODS

We lethally irradiated WT female mice and reconstituted their bone marrow using fetal liver cells from transgenic mice ubiquitously expressing green fluorescent protein. Periurethral collagen injection was used for bladder outlet obstruction. Obstruction was assessed by urodynamics, and bladder and kidney histological changes. Bladders were harvested 1 to 12 weeks after bladder outlet obstruction and compared to those in nonobstructed controls. The chemokine CCL2 was compared between obstructed and nonobstructed mice with reverse transcriptase-polymerase chain reaction. Green fluorescent protein expressing bone marrow derived cells were identified with immunohistochemistry and fluorescence activated cell sorting.

RESULTS

Bladders showed histological and urodynamic changes consistent with obstruction. CCL2 induction increased after obstruction compared to that in controls. After obstruction bone marrow derived cells were present in the urothelial and stromal layers. Activated epidermal growth factor receptor was found in cells associated with bone marrow derived cells.

CONCLUSIONS

Bone marrow derived cells are recruited to the bladder by bladder outlet obstruction and are present in the urothelial and stromal layers. Stromal bone marrow derived cells may have a role in hypertrophy and fibrosis. Further study of the recruitment and function of bone marrow derived cells in the bladder may provide potential targets for antifibrotic therapy.

Directed differentiation of bone marrow derived mesenchymal stem cells into bladder urothelium

PURPOSE

We have previously reported that embryonic rat bladder mesenchyma has the appropriate inductive signals to direct pluripotent mouse embryonic stem cells toward endodermal derived urothelium and develop mature bladder tissue. We determined whether nonembryonic stem cells, specifically bone marrow derived mesenchymal stem cells, could serve as a source of pluripotent or multipotent progenitor cells.

MATERIALS AND METHODS

Epithelium was separated from the mesenchymal shells of embryonic day 14 rat bladders. Mesenchymal stem cells were isolated from mouse femoral and tibial bone marrow. Heterospecific recombinant xenografts were created by combining the embryonic rat bladder mesenchyma shells with mesenchymal stem cells and grafting them into the renal subcapsular space of athymic nude mice. Grafts were harvested at time points of up to 42 days and stained for urothelial and stromal differentiation.

RESULTS

Histological examination of xenografts comprising mouse mesenchymal stem cells and rat embryonic rat bladder mesenchyma yielded mature bladder structures showing normal microscopic architecture as well as proteins confirming functional characteristics. Specifically the induced urothelium expressed uroplakin, a highly selective marker of urothelial differentiation. These differentiated bladder structures demonstrated appropriate alpha-smooth muscle actin staining. Finally, Hoechst staining of the xenografts revealed nuclear architecture consistent with a mouse mesenchymal stem cell origin of the urothelium, supporting differentiated development of these cells.

CONCLUSIONS

In the appropriate signaling environment bone marrow derived mesenchymal stem cells can undergo directed differentiation toward endodermal derived urothelium and develop into mature bladder tissue in a tissue recombination model. This model serves as an important tool for the study of bladder development with long-term application toward cell replacement therapies in the future.

Pediatric ureteroscopic management of intrarenal calculi

PURPOSE

Data addressing ureteroscopic management of intrarenal calculi in prepubertal children are limited. We reviewed our experience from January 2002 through December 2007.

MATERIALS AND METHODS

We retrospectively reviewed ureteroscopic procedures for intrarenal calculi in children younger than 14 years. Stone-free status was determined with postoperative imaging. Multiple logistic regression analysis was used to assess the influence of preoperative factors on initial stone-free status and the need for additional procedures.

RESULTS

Intrarenal calculi were managed ureteroscopically in 52 kidneys in 50 children with a mean age of 7.9 years (range 1.2 to 13.6). Mean stone size was 8 mm (range 1 to 16). Stone-free rate after a single ureteroscopic procedure was 50% (25 of 50 patients) on initial postoperative imaging and 58% (29 of 50) with extended followup. Initial stone-free status was dependent on preoperative stone size (p = 0.005) but not stone location. Additional stone procedures were required in 18 upper tracts. Younger patient age (p = 0.04) and larger preoperative stone size (p = 0.002) were associated with the need for additional procedures. Additional procedures were required in more than half of the stones 6 mm or larger but in no stone smaller than 6 mm.

CONCLUSIONS

Ureteroscopy is a safe method for the treatment of intrarenal calculi in the prepubertal population. Our ureteroscopic stone-free rate for intrarenal stones is lower than that reported for ureteral stones. Parents should be informed that additional procedures will likely be required, especially in younger patients and those with stones larger than 6 mm.

The impact of a fellowship on resident training in an academic pediatric urology practice

PURPOSE

The impact of a fellowship on resident operative experience and education is unclear. We sought to address this issue by comparing resident operative case logs and the pediatric portion of the American Urological Association resident inservice examination at our institution before and after establishing a pediatric urology fellowship in 2002.

MATERIALS AND METHODS

Pediatric operative case logs of all urological residents from 1998 to 2006 at Vanderbilt University were reviewed. We recorded index and total number of cases as specified by the Accreditation Council for Graduate Medical Education. All residents had completed 6 months of pediatric urology training. Statistical analysis was performed using 2-sample equal variance Student t tests. We compared the 8 index categories and total index cases performed by residents, scores on the pediatric portion of the American Urological Association inservice examination and resident average percentiles for index cases referenced to national data, before and after the implementation of an Accreditation Council for Graduate Medical Education accredited pediatric urology fellowship.

RESULTS

Before implementation of the pediatric urology fellowship residents performed significantly more hypospadias procedures, pyeloplasties, renal surgeries, ureteroneocystostomies and urinary/bowel diversions (p <0.05), while the total number of index cases performed was not significantly affected (p = 0.13). In contrast, after the fellowship was started residents performed more hydrocelectomies/hernia repairs (p = 0.01). Compared to national averages for index cases in 2004 to 2005, residents maintained greater than the 50th percentile in all categories except urinary diversion, which was between the 30th and 50th percentiles. Furthermore, residents were in the 70th to 90th percentile in 3 of 9 categories, and greater than the 90th percentile in 3, including total number of index cases. No statistically significant difference in the area of pediatric urology was observed on the resident inservice examination scores before and after the fellowship was established.

CONCLUSIONS

Residents performed significantly fewer index cases in some areas following initiation of a pediatric urology fellowship at Vanderbilt University, although the total number of index cases performed by residents remained unchanged. Despite the presence of a fellow, residents have remained at or well above the national average in all index case categories except urinary diversion. Moreover, establishment of a fellowship did not negatively impact the educational experience as measured by American Urological Association resident inservice examination scores, specifically in the area of pediatric urology. Choosing the optimal time to institute a fellowship should be made with fellow and resident education as the utmost priority. Periodic review of the data should also be performed to maintain consistent, positive experiences for fellowship and residency training.

Safety and efficacy of intratesticular injection of vital dyes for lymphatic preservation during varicocelectomy

PURPOSE

The most common complications of varicocelectomy include failure and hydrocele formation. Various surgical approaches have been used to minimize complications and guarantee durable results. The use of vital dyes to visualize and preserve testicular lymphatics intraoperatively has been proposed to reduce the incidence of hydrocele formation. We investigated the safety of intratesticular injection of various vital dyes and their efficacy in allowing visualization of lymphatics for varicocelectomy.

MATERIALS AND METHODS

Using general anesthesia, 22 adolescent rats underwent bilateral transscrotal intratesticular injection of methylene blue, isosulfan blue, trypan blue or normal saline. All rats with intratesticular injection of a vital dye underwent immediate exploration of the spermatic cord to observe for visualization of lymphatic vessels. At 3 months all rats were euthanized, and orchiectomy was performed for histological examination.

RESULTS

Spermatic cord lymphatic vessels were variably visualized depending on concentration and volume of the vital dye used. Histological examination of the testicles at 3 months after injection revealed areas with necrosis of seminiferous tubules, thickened tubular basement membranes, interstitial fibrosis and hyalinization, and striking intratubular dystrophic calcification. These pathological changes were present to varying degrees in all groups.

CONCLUSIONS

Although spermatic cord lymphatic channels were successfully visualized to varying degrees, intratesticular injection of vital dyes (and even normal saline) produced pathological changes in all groups, despite variation of concentration, volume and type of vital dye. Intratesticular injection of vital dyes for the visualization of lymphatics during varicocelectomy should be abandoned. Paratesticular injection of vital dyes should be used with caution.

Directed differentiation of embryonic stem cells into bladder tissue

Manipulatable models of bladder development which interrogate specific pathways are badly needed. Such models will allow a systematic investigation of the multitude of pathologies which result from developmental defects of the urinary bladder. In the present communication, we describe a model in which mouse embryonic stem (ES) cells are directed to differentiate to form bladder tissue by specific interactions with fetal bladder mesenchyme. This model allows us to visualize the various stages in the differentiation of urothelium from ES cells, including the commitment to an endodermal cell lineage, with the temporal profile characterized by examining the induction of specific endodermal transcription factors (Foxa1 and Foxa2). In addition, final functional urothelial differentiation was characterized by examining uroplakin expression. It is well established that ES cells will spontaneously develop teratomas when grown within immunocompromised mouse hosts. We determined the specific mesenchymal to ES cell ratios necessary to dictate organ-specific differentiation while completely suppressing teratomatous growth. Embryonic mesenchyme is well established as an inductive tissue which dictates organ-specific programming of epithelial tissues. The present study demonstrates that embryonic bladder mesenchyme can also steer ES cells towards developing specific endodermal derived urothelium. These approaches allow us to capture specific stages of stem cell differentiation and to better define stem cell hierarchies.

Evaluation of Superficial Bladder Transitional-Cell Carcinoma by Optical Coherence Tomography

BACKGROUND AND PURPOSE

Optical coherence tomography (OCT) is a new modality that allows noninvasive examination of the internal structure of biological tissue in vivo with a spatial resolution of 10 to 15 microm. This study evaluated the clinical application of OCT to determine epithelial and subepithelial anatomic structure and invasiveness of bladder epithelial lesions.

MATERIALS AND METHODS

The OCT examination was performed with a 980-nm 10 mW superluminescent diode using a 2.7-mm-diameter optical fiber positioned cystoscopically. A total of 261 scans of 1.5 seconds' duration, which generated 200 x 200-pixel images, were performed on 87 areas in 24 patients at high risk of having transitional-cell carcinoma (TCC). Lesions, visually suspect, and normal areas were photographed, scanned, and biopsied. The scans were evaluated independently before comparison with histopathology findings.

RESULTS

Of the 87 areas, 29 of 36 visually suspect areas and 35 of 35 normal areas, were correctly diagnosed with OCT. Of the 16 areas with papillary TCC, all 16 were diagnosed correctly as tumor, and 9 of 10 were diagnosed correctly as invasive, including 6 with lamina propria invasion only. Papillary and flat tumors, carcinoma in situ, inflammation, chronic cystitis, and von Brunn's nests were scanned. Overall, OCT had a sensitivity of 100%, overall specificity of 89%, positive predictive value of 75%, and negative predictive value of 100%. The accuracy was 92%. The positive predictive value for invasion was 90%.

CONCLUSION

Optical coherence tomography is a simple, portable, promising modality for evaluation of bladder lesions and depth of tumor penetration. Further refinement of this technology may lead to the development of an optical surrogate for biopsy.