Michelle Lightfoot

Diagnosis and management of ureteral fibroepithelial polyps in children: A new treatment algorithm

INTRODUCTION Fibroepithelial polyps are benign mesenchymal tumors arising from the urinary tract. With the advent of endoscopy in the pediatric population, more reports of endoscopic diagnosis and treatment have appeared. OBJECTIVE The present study reports experience with the diagnosis and treatment of fibroepithelial polyps of the upper urinary tract in the pediatric population. Incorporating past experience from literature, we propose an algorithm to guide the clinical diagnosis and treatment plan. STUDY DESIGN Four pediatric patients undergoing pyeloplasty for ureteropelvic junction (UPJ) obstruction were diagnosed with ureteral polyps. Their demographics, radiologic, surgical and pathologic information were reviewed. In addition, a comprehensive literature search using the MEDLINE database yielded 37 reports containing 126 cases of ureteral polyps, including 5 series with 57 cases and 9 cases of synchronous bilateral ureteral polyps. RESULTS Of 123 pediatric patients undergoing pyeloplasty from 2008 to 2013, four (3.3%) were found to have fibroepithelial polyps of the upper urinary tract. All patients were male and the mean age of presentation was 12 years. Ureteral polyps predominantly occurred unilaterally in the left ureter (75%) and one case of bilateral ureteral polyps was encountered. Along with three other recent case series [1-3], the combined incidence of ureteral polyps in patients undergoing evaluation for ureteral obstruction was 5.2%. Intraoperative retrograde pyelogram was used to identify filling defects in 4 of 5 affected ureters (see Figure). Ureterorenoscopy was performed in all three patients with filling defects for polyp mapping along the ureter and evaluation of the macroscopic polyp appearance. Based on ureteroscopic findings, Holmium laser polypectomy was performed in two patients with single, pedunculated polyps. Anderson-Hynes dismembered pyeloplasty was performed in three patients with broad based, multilobulated polyps too large for endoscopic treatment and in one patient for undiagnosed polyp prior to pyeloplasty. DISCUSSION The present study finds that the 5.2% combined incidence of ureteral polyps in contemporary reports may be higher than previously described [4]. Retrograde pyelogram was an effective tool in diagnosing ureteral polyp and ureteroscopy can be employed if ureteral polyps are suspected for both diagnostic and therapeutic purposes. Although clinical experience is limited, endoscopic laser treatment seems to be effective for the single, pedunculated ureteral polyps, while dismembered pyeloplasty is required for the broad based, multilobulated polyps. The study was limited by the rarity of ureteral polyps. Future multi-institutional collaborative studies are required to validate the diagnostic and treatment algorithm proposed. CONCLUSION Ureteral polyps cause approximately 5% of UPJ obstruction in the pediatric population. Diagnosis can be made in certain cases by intraoperative retrograde pyelogram. If a filling defect is encountered, ureteroscopy is indicated for polyp mapping. The treatment modality is dictated by the endoscopic appearance of the ureteral polyp.

Transurethral needle biopsy: A novel technique for pathologic diagnosis of bladder tumors in children

Although rare, both benign and malignant bladder tumors are occasionally encountered in the pediatric population. In the present article, the technique of transurethral needle biopsy, which utilizes an 18-gauge core biopsy instrument inserted through a 9.5 French offset pediatric cystoscope to obtain diagnostic biopsies, is described. This technique has been used successfully in two patients, both of whom had an inflammatory myofibroblastic tumor on biopsy and on final pathology from partial cystectomy. This provides an alternative technique, which may be used when a pediatric resectoscope is not available or in patients with a small caliber urethra.

Unsuccessful foley catheterization had an unexpected explanation.

Background Foley catheterization is a simple procedure routinely performed during many obstetric and gynecologic procedures. Failure to adequately drain the bladder with catheter insertion should prompt further investigation to minimize morbidity to the patient. Case After repeated attempts to place a Foley catheter during a cesarean section, the urinary bladder did not drain. Postoperatively, it was found that the catheter was positioned inside the left ureter, and cystoscopy confirmed an ectopic ureter inserting into the proximal urethra. Conclusions This case presents an unusual cause of oliguria in an operative patient requiring Foley catheterization. An ectopic ureteral orifice should be considered in the differential diagnosis of a patient presenting with unexplained oliguria or anuria and failure to decompress the bladder with catheter placement.

V9-05 A SIMPLIFIED TECHNIQUE FOR PERFORMANCE OF FLUOROLESS URETEROSCOPY

INTRODUCTION AND OBJECTIVES: Percutaneous nephrolithotomy (PCNL) remains a challenging procedure associated with significant potential for patient morbidity. In an attempt to decrease the morbidity of PCNL, we have developed a novel technique employing direct visualization with ureteroscopy to decrease ambiguity associated with fluoroscopy guidance, while eliminating ionizing radiation exposure. In this video, we demonstrate PCNL techniques that obviate the need for fluoroscopy. METHODS: This video demonstrates fluoroless PCNL in a 56 year-old female with large left renal stone burden (>4 cm). The patient was positioned prone and split-leg. Utilizing visual and tactile cues, a super-stiff and standard guidewire were placed from below using a flexible cystoscope. Using flexible ureteroscopy, the ideal calyx for access was selected. Under ultrasound guidance, an access needle was placed into the selected calyx, which was directly visualized on ureteroscopy. With the aid of a stone basket, an access wire was pulled into the ureter to allow for subsequent exchange to a super-stiff guidewire. Under direct visualization with the ureteroscope, the balloon and access sheath were positioned. The ureteroscope was left with the tip occluding the ureteropelvic junction to prevent distal migration of fragments. Stone comminution was accomplished with an ultrasonic lithotripter. Stone-free status was assured intraoperatively using a combination of flexible nephroscopy and ureteroscopy. A nephrostomy tube and multipurpose angled ureteral catheter were placed under direct vision ureteroscopically to conclude the procedure. RESULTS: Operative time was 4 hours 36 minutes. Estimated blood loss was <50 mL. On post-operative day one, a 15 mAs low-dose CT (<1 mSv) demonstrated stone-free status. CONCLUSIONS: This technique combines the methods of many pioneering endourologic surgeons in a unique way to perform PCNL under direct visualization. We believe this technique offers significant promise both by eliminating uncertainties encountered when operating under fluoroscopic guidance and reducing the risk of radiation exposure to patients and operating room staff.

MP20-05 VARIATIONS IN INTRAPELVIC RENAL PRESSURES DURING PERCUTANEOUS NEPHROLITHOTOMY – A PORCINE STUDY

INTRODUCTION AND OBJECTIVES: It has been established that high intrapelvic pressures (IPP) may cause possible spread of infection through pyelo-venous backflow while lower pressures can hinder surgeon’s visualization, decrease venous tamponade and result in increased bleeding. The purpose of this study is to characterize IPP during percutaneous nephrolithotomy. METHODS: A porcine model was utilized to test IPP during rigid and flexible nephroscopy. Pressures were compared in a variety of conditions including single versus two tract access, rigid versus flexible nephroscopy and presence versus absence of suction. Twenty trials were performed for each condition. An independent samples MannWhitney U test was used to compare parameters, with p<0.05 considered statistically significant. RESULTS: In the single tract model, rigid nephroscopy resulted in significantly higher mean pressure (31.35 mmHg) compared to flexible nephroscopy (10.7 mmHg; p < 0.001). The pressure was higher when using a rigid nephroscope in a single tract (31.35 mmHg) compared to when two tracts were present (9.35 mmHg; p < 0.001). In contrast, there was no difference between the flexible nephroscope in a single tract (10.7 mmHg) versus with two tracts (10.9 mmHg; p 1⁄4 0.63) Use of suction with the rigid nephroscope resulted in significantly lower pressure when only one tract was present (-1.3 mmHg) compared to when two tracts were present (1.8 mmHg; p 1⁄4 0.004). CONCLUSIONS: This study demonstrates that addition of a second tract may result in significant alterations in renal IPP, with much lower pressures when using irrigation but higher pressures when using suction when compared to a single tract. This may explain in part why transfusion rates are significantly higher with multiple accesses during PCNL.