Lesli I. Nicolay

Effect of Low Dose Radiation Computerized Tomography Protocols on Distal Ureteral Calculus Detection

PURPOSE Unenhanced multidetector computerized tomography is the imaging modality of choice for urinary calculi but exposes patients to substantial radiation doses with a subsequent risk of radiation induced secondary malignancy. We compared ultra low dose and conventional computerized tomography protocols for detecting distal ureteral calculi in a cadaveric model. MATERIALS AND METHODS A total of 85 calcium oxalate stones 3 to 7 mm long were prospectively placed in 14 human cadaveric distal ureters in 56 random configurations. The intact kidneys, ureters and bladders were placed in a human cadaveric vehicle and computerized tomography was performed at 140, 100, 60, 30, 15 and 7.5 mA seconds while keeping other imaging parameters constant. Images were independently reviewed in random order by 2 blinded radiologists to determine the sensitivity and specificity of each mA second setting. RESULTS Overall sensitivity and specificity were 98% and 83%, respectively. Imaging using 140, 100, 60, 30, 15 and 7.5 mA second settings resulted in 98%, 97%, 97%, 96%, 98% and 97% sensitivity, and 83%, 83%, 83%, 86%, 80% and 84% specificity, respectively. Interobserver agreement was excellent (kappa >0.87). There was no significant difference in sensitivity or specificity at any mA second settings. All false-negative results were noted for 3 mm calculi at a similar frequency at each mA second setting. CONCLUSIONS Ultra low dose computerized tomography protocols detected distal ureteral calculi in a fashion similar to that of conventional computerized tomography protocols in a cadaveric model. These protocols may decrease the radiation dose up to 95%, reducing the risk of secondary malignancies.

A Prospective Randomized Comparison of Traditional Laparoendoscopic Single-Site Surgery with Needlescopic-Assisted Laparoscopic Nephrectomy in the Porcine Model

BACKGROUND AND PURPOSE Laparoendoscopic single-site (LESS) surgery produces virtually no scar but is technically challenging because of the loss of triangulation. The objective of this study is to compare classic transumbilical LESS nephrectomy with needlescopic-assisted laparoscopy (NAL) surgery. In doing so, we evaluated whether the addition of a single 2-mm subcostal port could restore triangulation while not jeopardizing recovery or cosmetic outcome in the porcine model. MATERIALS AND METHODS Ten female farm pigs were randomized to laparoscopic nephrectomy with either LESS or NAL. In LESS, a TriPort was placed through a single 2.5-cm umbilical incision. In NAL, 5- and 10-mm ports were placed in the umbilicus and a 2-mm port was placed in the midclavicular line. Preoperative, perioperative, and postoperative parameters were compared. Variables were analyzed with the Wilcoxon signed-rank test and two-tailed Fisher exact test. Cosmesis was evaluated objectively using the Vancouver Scar Scale and subjectively by a blinded dermatologist. A cost analysis was performed. RESULTS Estimated blood loss was minimal in both groups (28.8 mL in LESS and 9.4 mL in NAL). Operative time was significantly shorter in NAL (103 vs 150 min; P<0.001). There was no difference in complications (2 vs 1; P=0.500), objective cosmesis (3.9 vs 3.8; P>0.2), or subjective cosmesis (2 vs 3; P=0.500). The NAL protocol had significantly lower disposable equipment costs (

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

363 vs

Vessel Length Following Laparoscopic Donor Nephrectomy: Impact of Vascular Ligation Technique on Allograft Vessel Length

1696). CONCLUSIONS The addition of a 2-mm subcostal port and the restoration of triangulation in the NAL protocol enable shorter operative times, increased surgeon comfort, improved technical ease, and lower costs while maintaining the scarless cosmesis of the traditional LESS protocol.

Ocular Complications After Open and Hand-assisted Laparoscopic Donor Nephrectomy

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

PURPOSE A variety of techniques have been used to secure the renal artery and vein during laparoscopic donor nephrectomy. The purpose of this study is to compare the amount of vessel length lost when the artery and vein are secured with four different techniques. METHODS A model was constructed to simulate a left laparoscopic donor nephrectomy. In this model vessel length lost was determined when veins were secured using polymer locking (PL) clips, the endo-GIA stapling device, and the endo-TA stapling device. Arterial length lost was determined for the same three techniques, as well as securing the artery with titanium (Ti) clips. RESULTS The mean arterial length lost for the PL clips, Ti clips, endo-TA, and endo-GIA stapling devices was 6.2, 6.3, 9.8, and 10.0 mm, respectively. Both clip types produced less loss of arterial length than both types of stapling devices (P<0.001), and there was no difference between the two types of stapling devices (P=0.73) or clips (P=0.85). The mean venous length lost for the PL clip, endo-GIA, and endo-TA stapling devices was 5.7, 10.1, and 9.4 mm, respectively. The PL clips resulted in significantly less vessel loss compared to both stapling devices (P<0.001), and there was no difference between the two stapling devices (P=0.40). CONCLUSIONS Both types of clips resulted in longer graft arterial lengths compared to both stapling devices. PL clips resulted in longer graft vein length compared to the two stapling devices. The endo-TA stapling device was limited in this model by its inability to articulate.

Principles of Ultrasound

OBJECTIVES To compare the incidence of ocular complications (OC) and corneal abrasion (CA) after hand-assisted laparoscopic donor nephrectomy (HALDN) and open donor nephrectomy (ODN). METHODS A retrospective review was conducted of 241 consecutive patients (141 HALDN and 100 ODN) over a 9-year period. OC were strictly defined as ocular complaints requiring any treatment or ophthalmologic consultation. Chi-square tests were used to compare the incidence of OC and CA by type of surgery. RESULTS OC were observed in 9 HALDN patients (6.4%) and no ODN patients (0%; P = .01). All OC in HALDN patients involved the dependent eye (P <.001). CA occurred in 2 HALDN patients (1.4%) compared with no ODN patients (0%; P = .23). HALDN patients had significantly higher net fluid intake than the ODN patients (P <.01). CONCLUSIONS The increased OC and CA seen in HALDN patients may result from the increased fluid intake, flank positioning, and potential increased venous compression resulting from the effects of the pneumoperitoneum. The fact that the dependent eye was involved in all patients suggests conjunctival edema as a potential common pathway. The high frequency of OC suggests the importance of techniques to minimize OC after HALDN.

Laparoscopy and RoboticsReply

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.

A Novel Bridging Hand-Assisted LESS Donor Nephrectomy Technique

Ultrasound is the most common and first-line imaging study performed in the genitourinary tract in children. It is used for screening and monitoring children even before birth. We provide a primer for the reader to understand the pertinent physics of ultrasonography by reviewing the physical properties of sound waves and their ability to capture images. Artifacts created by these physical properties are sometimes of diagnostic utility. The indications for performing ultrasound studies are described followed by a discussion of the technique and expected finding of normal ultrasound studies of the kidney, bladder, and testis in children.