Step-by-Step robotic heminephrectomy for duplicated renal collecting system.

INTRODUCTION: A duplicated renal collecting system is a relatively common congenital anomaly rarely presenting in adults. AIM: In this video we demonstrate our step-by-step technique of Robotic heminephrectomy in a patient with non-functioning upper pole moiety. MATERIALS AND METHODS: Following cystoscopy and ureteral catheter insertion the patient was placed in 60° modified flank position with the ipsilateral arm positioned at the side of the patient. A straight-line, three arm robotic port configuration was employed. The robot was docked at a 90-degree angle, perpendicular to the patient. Following mobilization the colon and identifying both ureters of the duplicated system, the ureters were followed cephalically toward, hilar vessels where the hilar anatomy was identified. The nonfunctioning pole vasculature was ligated using hem-o-lok clips. The ureter was sharply divided and the proximal ureteral stump was passed posterior the renal hilum. Ureteral stump was used as for retraction and heminephrectomy is completed along the line demarcating the upper and lower pole moieties. Renorrhaphy was performed using 0-Vicryl suture with a CT-1 needle. The nonfunctioning pole ureter was then dissected caudally toward the bladder hiatus, ligated using clips, and transected. RESULTS: The operating time was 240 minutes and blood loss was 100 cc. There was no complication post-operatively. CONCLUSIONS: Wrist articulation and degree of freedom offered by robotic platform facilitates successful performance of minimally invasive heminephrectomy in the setting of an atrophic and symptomatic renal segment.

Phenotypic characterization of kidney stone formers by endoscopic and histological quantification of intrarenal calcification.

Interstitial Randall's plaques and collecting duct plugs are distinct forms of renal calcification thought to provide sites for stone retention within the kidney. Here we assessed kidney stone precursor lesions in a random cohort of stone formers undergoing percutaneous nephrolithotomy. Each accessible papilla was endoscopically mapped following stone removal. The percent papillary surface area covered by plaque and plug were digitally measured using image analysis software. Stone composition was determined by micro-computed tomography and infrared analysis. A representative papillary tip was biopsied. The 24-h urine collections were used to measure supersaturation and crystal growth inhibition. The vast majority (99%) of stone formers had Randall's plaque on at least 1 papilla, while significant tubular plugging (over 1% of surface area) was present in about one-fifth of patients. Among calcium oxalate stone formers the amount of Randall's plaque correlated with higher urinary citrate levels. Tubular plugging correlated positively with pH and brushite supersaturation but negatively with citrate excretion. Lower urinary crystal growth inhibition predicted the presence of tubular plugging but not plaque. Thus, tubular plugging may be more common than previously recognized among patients with all types of stones, including some with idiopathic calcium oxalate stones.

Collecting system percutaneous access using real-time tracking sensors: first pig model in vivo experience.

PURPOSE: Precise needle puncture of the renal collecting system is an essential but challenging step for successful percutaneous nephrolithotomy. We evaluated the efficiency of a new real-time electromagnetic tracking system for in vivo kidney puncture. MATERIALS AND METHODS: Six anesthetized female pigs underwent ureterorenoscopy to place a catheter with an electromagnetic tracking sensor into the desired puncture site and ascertain puncture success. A tracked needle with a similar electromagnetic tracking sensor was subsequently navigated into the sensor in the catheter. Four punctures were performed by each of 2 surgeons in each pig, including 1 each in the kidney, middle ureter, and right and left sides. Outcome measurements were the number of attempts and the time needed to evaluate the virtual trajectory and perform percutaneous puncture. RESULTS: A total of 24 punctures were easily performed without complication. Surgeons required more time to evaluate the trajectory during ureteral than kidney puncture (median 15 seconds, range 14 to 18 vs 13, range 11 to 16, p=0.1). Median renal and ureteral puncture time was 19 (range 14 to 45) and 51 seconds (range 45 to 67), respectively (p=0.003). Two attempts were needed to achieve a successful ureteral puncture. The technique requires the presence of a renal stone for testing. CONCLUSIONS: The proposed electromagnetic tracking solution for renal collecting system puncture proved to be highly accurate, simple and quick. This method might represent a paradigm shift in percutaneous kidney access techniques.

Tubulocystic renal carcinoma (low grade collecting duct carcinoma).

OBJECTIVE: To report a case of tubulocystic renal carcinoma diagnosed in an adult, after a work up study for hematuria. METHODS/RESULTS: 59-year-old male, CT scan was performed during a study for self-limited hematuria showing a 4.2 cm solid mass with areas suspicious of pseudocystic malignancy. Due to its debut with hematuria and renal sinus involvement laparoscopic radical nephrectomy was performed, establishing the diagnosis of tubulocystic carcinoma (low grade collecting duct carcinoma). CONCLUSION: Tubulocystic carcinoma presents histological characteristics and a natural history that makes it different from the classic type of Bellini duct carcinoma, the latter being a rapidly growing tumor with poor prognosis which is usually diagnosed in advanced stages.

Protection of the renal collecting system during radiofrequency ablation with antegrade cold dextrose infusion.

PURPOSE: To evaluate the feasibility and efficacy of antegrade renal cooling during radiofrequency (RF) ablation to protect the renal collecting system in pigs. MATERIALS AND METHODS: With the approval of the institutional animal care and use committee, RF ablation was planned bilaterally after nephrostomy in 20 kidneys from 10 domestic pigs. A coaxial assembly consisting of a 7-F pigtail catheter and a 12-F arterial sheath was placed at the renal pelvis. Cooled 5% dextrose in water solution was perfused in only one of the kidneys in each pig. A 17-gauge internally cooled tip RF electrode with a 3-cm tip was placed near the renal pelvis with ultrasonographic guidance. On postprocedural days 1 and 7, computed tomography (CT) was performed to evaluate the RF ablation effect, the presence of a fluid collection, and the leakage of contrast material. Ex vivo retrograde pyelography was performed to assess the integrity of the urinary tract after kidney harvest. Histologic findings related to the urothelial damage were scored semiquantitatively. RESULTS: The mean maximal diameter of the RF ablation area measured at CT and in specimens was not significantly different between cooled and noncooled kidneys. A fluid collection around the RF ablation area was seen in eight of the 10 noncooled kidneys on day 7 CT scans compared with two of the 10 cooled kidneys; the difference was statistically significant (P = .035). Ex vivo retrograde pyelography depicted leakage of contrast material in only the noncooled group. The mean histologic damage score was lower in the cooled group than in the noncooled group. CONCLUSION: RF ablation after placement of an antegrade cooling system in pig kidneys was feasible. Antegrade cold dextrose infusion of the urinary tract during RF ablation is effective in protecting the renal collecting system without compromising the RF ablation effect.

SabreSource™: a novel percutaneous nephrolithotomy apparatus to aid collecting system puncture - a preliminary report.

BACKGROUND: Successful percutaneous nephrolithotomy (PCNL) relies on a technically challenging, precise needle puncture of the renal collecting system. We aimed to compare, in an ex vivo model, the use of a real time image guidance system (the SabreSource™) and a mechanical stabilising device with conventional manual techniques for the accuracy of needle placement. METHODS: The SabreSource™ system (Minrad International Inc.; New York, USA) is a real time image guidance system. The system platform is mounted on a C-arm fluoroscope. It employs targeting cross hairs on the fluoroscopic image that can be easily positioned to target the desired renal calyx. The system directs a visible laser beam onto the patient which is precisely aligned with the cross hairs on the fluoroscopic image. This provides the correct "bull's-eye" angle of approach to the calyx, even after the x-ray source is turned off. The locator then stabilises the needle in the "bull's-eye" position so that only screening for depth is required. Objective assessment using a simulated PCNL puncture was performed by 7 urologic trainees on a kidney phantom with and without using the SabreSource™. Fluoroscopy screening time (FST) and amount of radiation (mGy) used to achieve successful puncture were compared. RESULTS: Simulated PCNL puncture was quicker and resulted in reduced radiation exposure when the apparatus was used. The mean FST for traditional "bull's-eye" vs SabreSource™ puncture was 17 vs 5 seconds (p = 0.01), and the mean radiation exposure to puncture was 0.7 vs 0.2 mGy (p = 0.03), respectively. CONCLUSION: The SabreSource™ is a novel assistant to achieving successful PCNL puncture. In combination with "the locator" the preliminary in vitro testing suggests that the device reduces fluoroscopy exposure and is quicker. The device warrants further evaluation in the clinical setting.

[Laparoscopic pyeloplasty in a complicated duplicated collecting system]. / Laparoskopische Nierenbeckenplastik bei komplizierter Doppelniere.

Laparoscopic pyeloplasty has been established as an effective and minimally invasive technique for treating ureteropelvic junction obstruction. Only case reports are available describing the use of laparoscopic pyeloplasty in patients with duplicated collecting systems. We report the case of a patient presenting with a short stenotic connection between the hydronephrotic lower pole system and a solitary ureter coming from the upper pole. In this patient, a side-to-side anastomosis between the renal pelvis and the ureter was successfully performed. The present data demonstrate that laparoscopic pyeloplasty is an applicable tool even in patients with upper urinary tract anomalies such as duplicated collecting systems.

Impact of collecting-system repair during laparoscopic partial nephrectomy.

PURPOSE: Laparoscopic partial nephrectomy (LPN) is a complex procedure frequently reserved for small, peripherally located renal tumors. Deep, infiltrating lesions often necessitate collecting system repair (CSR), mandating further intracorporeal suturing and reconstruction. We compared our experience with LPN where CSR was and was not required after tumor resection. PATIENTS AND METHODS: Between October 2002 and December 2005, 84 patients underwent LPN. Tumor excision with pelvicaliceal system injury occurred in 52 patients, whereas 32 patients required no CSR. Perioperative and pathologic data were compared in the two groups. RESULTS: Tumors with CSR were larger (mean 2.9 cm v 2.1 cm for non-CSR procedures; P = 0.001) and had larger pathologic specimen weights (mean 58.2 g v 21.8 g; P = 0.05). Blood loss (mean 210 mL) and hospital stay (mean 2.7 days) were similar in the two groups. Warm ischemia time (WIT) (mean 36.6 v 27.7 minutes; P < 0.001) and operative time (mean 238 v 207 minutes; P = 0.03) were longer in the CSR group. The intraoperative hemorrhage rate (7.7% v 9.4%; P = 0.34) and rate of conversion to open surgery (7.7% v 9.4%; P = 0.29) were similar, as were the incidences of postoperative bleeding (7.7% v 3.1%; P = 0.28) and urinary leakage (1.9% v 0; P = 0.62). CONCLUSION: Laparoscopic partial nephrectomy involving CSR is a technically demanding procedure that necessitates longer WIT and overall surgical time. However, when performed by an experienced laparoscopic surgeon, comparable complication rates and blood loss are observed. Technical variations for hemostasis, such as argon-beam coagulation and FloSeal and the use of the LapraTy clip for pelvicaliceal and parenchymal suture repair may facilitate LPN for more deeply invasive tumors.

Robot-assisted laparoscopic lower pole partial nephrectomy in the pediatric patient.

INTRODUCTION: In pediatric urology, partial nephrectomy is used primarily to remove a non-functioning renal moiety in a duplicated system. There are few data on infants undergoing this procedure. As such, we present a robot-assisted laparoscopic lower pole partial nephrectomy in an infant. METHODS: Our patient was an 11-month-old (10.7 kg) male with a history of prenatal hydronephrosis, who was diagnosed postnatally with a duplicated right collecting system and severe hydroureteronephrosis of the right lower collecting system. A DMSA scan demonstrated no radiotracer uptake in the right lower pole. A robot-assisted laparoscopic lower pole partial nephrectomy was performed. RESULTS: A lower pole partial nephrectomy was accomplished. At 1 month postoperatively, an ultrasound demonstrated no hydronephrosis or perinephric fluid collection. CONCLUSIONS: Robotic partial nephrectomy is safe and feasible in pediatrics including both older children and infants. It is successful for both upper and lower pole partial nephrectomies.

Duplicated Renal Collecting System With Ectopic Ureter in Female Bladder Exstrophy: A Case Report.

Bladder exstrophy is a rare major birth defect which requires specialized surgical care. Associated genitourinary tract anomalies are extremely rare in this population, yet significantly impact surgical planning and outcomes. In this case, a full-term newborn girl with a prenatal diagnosis of classic bladder exstrophy was found to have a complete duplicated left collecting system with an ectopic ureter inserted to urethral plate. The patient underwent modern staged repair of exstrophy with bilateral anterior innominate osteotomies and concomitant ureteral reimplantation-the first reported case of ureteral reimplantation at the time of initial closure in a newborn.

Robot assisted heminephrectomy for duplicated renal collecting system: technique and outcomes.

BACKGROUND: The aim of this study was to describe experience with robotic assisted hemi-nephrectomy (RAHN) for the management of duplicated renal collecting system. METHODS: The authors' institutional database was queried to identify patients who underwent RAHN from 2007 to 2013 for the management of a duplicated system. Patient demographics, indications and surgical outcomes were reviewed and analyzed. RESULTS: Five patients were identified with a duplicated system of which all had a history of pain and recurrent infection. Three patients underwent hemi-nephrectomy for a poorly functioning lower pole and two for an abnormal upper pole moiety. All operations were completed successfully using a robotic approach. There were only two minor (Clavien grade 1-2) complications. CONCLUSIONS: RAHN is a viable option for the surgical treatment of an atrophic, chronically infected duplicated system. The unique features of robotic technology offer enhanced dexterity and vision facilitating the management of complex vascular and ureteral anatomy.

Gross haematuria associated with penetration of an inferior vena cava filter into the right renal collecting system.

Inferior vena cava (IVC) filters are a viable alternative for patients with venous thromboembolic disease for whom standard anticoagulation therapy is contraindicated. Rare complications associated with their use, however, include misplacement and IVC penetration. We report a case of a 63-year-old woman who developed gross haematuria following IVC filter penetration into both the right renal collecting system and renal pelvis, for which open caval removal and reconstruction was required. This is an unusual case of IVC filter penetration causing symptomatic haematuria and requiring surgical intervention.

Ureteropelvic junction obstruction in upper and lower moiety of duplex renal systems.

OBJECTIVES: To review our experience with ureteropelvic junction obstruction in a duplicated renal collecting system. METHODS: The records of 7 patients with ureteropelvic junction obstruction in a duplex collecting system were reviewed. In addition to routine demographics, each case was reviewed for presenting symptoms, site of obstruction, and type of surgical treatment. RESULTS: Three of the 7 cases involved obstruction of the upper pole moiety, and the remaining 4 involved the lower pole segment of a duplex system. Obstruction of the upper and lower pole segments was found in both incomplete and complete duplicated collecting systems. CONCLUSIONS: Careful preoperative evaluation of patients with ureteropelvic junction obstruction will usually identify segmental obstruction in a duplicated system. Treatment should be individualized based on site of obstruction and degree of function remaining in the affected segment.

Pancreatic pseudocyst rupture into the renal collecting system.

Pseudocyst formation is a well-recognized complication of pancreatitis. Involvement of a pseudocyst with the kidney is rare. We report an unusual case of a pancreatic pseudocyst with rupture into the renal collecting system. The surgical management of this problem is described and the world-wide experience is reviewed briefly.

Use of fibrin glue and gelfoam to repair collecting system injuries in a porcine model: implications for the technique of laparoscopic partial nephrectomy.

BACKGROUND AND PURPOSE: One of the challenges of laparoscopic partial nephrectomies is the repair of a collecting system injury. We hypothesized that fibrin glue plus Gelfoam could be sufficient to repair such injuries. MATERIALS AND METHODS: Four pigs (eight kidneys) underwent collecting system injuries of various lengths (3, 5, and 10 mm) (N = 8 each) during partial nephrectomy. Gelfoam soaked in the fibrin glue was applied to seal the collecting system and parenchymal defects. After 1 hour of passive filling, the renal pelvis was distended at supraphysiologic pressure to the point of leakage. Each repair site was examined for urinary extravasation during the physiologic and active phases of filling. RESULTS: Hemostasis was achieved, and all collecting system injuries, regardless of size, were free of urinary leakage at physiologic pressures. Moreover, all defects maintained a seal at supraphysiologic pressures of at least 50 cm H(2)O. CONCLUSION: The combined use of fibrin glue and Gelfoam is an effective means to obtain hemostasis and seal collecting system injuries up to 10 mm at physiologic pressures and up to 50 cm H(2)O in the acute setting. Our hope is that this technique can facilitate both laparoscopic and open partial nephrectomies. New technologies will be employed in an attempt to obtain better seating of the sealant plug in the future. Survival studies are in progress.

Successful management of lower-pole moiety ureteropelvic junction obstruction in a partially duplicated collecting system using minimally invasive retrograde endoscopic techniques.

Although the true incidence of ureteropelvic junction (UPJ) obstruction in the lower-pole moiety of an incompletely duplicated renal collecting system remains elusive, the description of this entity in the published literature is exceedingly rare. To our knowledge, we report the first case of this entity managed successfully by ureteroscopic holmium laser incision of the stenotic UPJ segment. This case underscores the utility of minimally invasive techniques in the management of selected cases of UPJ obstruction associated with a partially duplicated collecting system.

Duplicated collecting system with lower pole ureteropelvic junction obstruction.

Two examples of the rare case of complete duplicated collecting system with lower pole ureteropelvic junction obstruction are described. Ureteropelvic junction obstruction (UPJO) and duplicated collecting systems seldom occur in combination. Complete duplication of the ureter may be asymptomatic or recognized when complications develop as a result of reflux into the lower pole ureter or obstruction of the upper pole with an ectopic ureterocele. It is difficult to choose an optimal therapy due to the high variability in function, degree of obstruction, damage and potential for regeneration in growing kidneys. The diagnosis and management of UPJO of the lower pole in complete duplicated collecting systems are discussed.

Collecting duct carcinoma arising in a solitary kidney: imaging findings.

Collecting duct carcinoma is an aggressive malignancy derived from the renal medulla. Imaging features suggestive of this diagnosis include a medullary origin, hypovascularity, and an infiltrative growth pattern. A case of collecting duct carcinoma with unsuspected contralateral renal agenesis is presented.