Retrograde vs. antegrade flexible nephroscopy for detection of residual fragments following PNL: a prospective study with computerized tomography control

ABSTRACT Introduction: The main aim of stone surgery is to establish stone free status. Performing flexible nephroscopy is an effective tool in this manner. The aim of this study was to evaluate the role of retrograde flexible nephroscopy for detection of residual fragments following percutaneous nephrolithotomy (PNL) in comparison with antegrade approach. Materials and Methods: Data of 137 patients underwent ECIRS was collected prospectively. In all cases following stone clearance, collecting system was checked for residual fragments. First antegrade than retrograde flexible nephroscopy was performed and success rates to reach all calices and detection of residual fragments were noted. All patients underwent CT and success rate of antegrade and retrograde approaches were compared. PPV and NPV of retrograde approach to detect residual fragments were calculated. Results: Antegrade and retrograde nephroscopy successfully accessed all of the calices in 101 (73.7%) and 130 (94.9%) patients respectively (p<0.0001). Residual fragments were observed in 18 (13.1%) patients following antegrade flexible nephroscopy. Retrograde approach identified residual stones in 17 more cases. These cases were treated with flexible nephroscopy or secondary percutaneous tract. Postoperative CT revealed residual stones in 10 (7.3%) patients. PPV and NPV of retrograde flexible nephroscopy were 83.3% and 96.2%. Conclusions: Flexible nephroscopy effectively detects residual fragments following PNL. Retrograde approach was more successful than antegrade approach to reach all calices. We recommend performing retrograde flexible nephroscopy following PNL especially in complex cases as it has the potential to increase SFR, decrease the need for second look surgery and unnecessary postoperative imaging.

Ureterocalycostomy - final resort in the management of secondary pelvi-ureteric junction obstruction: our experience

ABSTRACT: Ureterocalycostomy can be performed in patients in whom desired methods of treating secondary PUJ (Pelvi-Ureteric Junction) obstructions either failed or could not be used. In our study, one child and two adults in whom one redo-ureterocalycostomy and two ureterocalycostomies were performed for severely scarred PUJ. The causes for secondary PUJ obstruction were post-pyelolithotomy in one case, post-pyeloplasty and ureterocalycostomy for PUJ obstruction in the second patient and the third patient had long upper ureteric stricture post-ureteropyeloplasty due to tuberculosis. In all these cases ureterocalycostomy proved to be salvage/final resort for preserving functional renal unit

A Novel method of ensuring safe and accurate dilatation during percutaneous nephrolithotomy

ABSTRACT Objective: To report our technique that helps locate the guidewire into the ureter enabling safe dilatation during PCNL. Materials and Methods: Cases in which the guidewire failed to pass into the ureter following successful puncture of the desired calyx were subjected to this technique. A second guidewire was passed through the outer sheath of a 9 Fr. metallic dilator cannula, passed over the first guidewire. The cannula and outer sheath were removed, followed by percutaneous passage of a 6/7.5 Fr ureteroscope between the two guidewires, monitoring its progress through both the endoscopic and fluoroscopic monitors. Once the stone was visualized in the calyx a guidewire was passed through the working channel and maneuvered past the stone into the pelvis and ureter under direct endoscopic vision. This was followed by routine tract dilatation. Results: This technique was employed in 85 out of 675 cases of PCNL carried out at our institute between Jan 2010 to June 2014. The mean time required for our technique, calculated from the point of introduction of the ureteroscope untill the successful passage of the guidewire down into the ureter was 95 seconds. There were no intraoperative or postoperative complications as a result of this technique. Guidewire could be successfully passed into the ureter in 82 out of 85 cases. Conclusions: Use of the ureteroscope introduced percutaneously through the puncture site in PCNL, is a safe and effective technique that helps in maneuvering the guidewire down into the ureter, which subsequently enables safe dilatation.

Percutaneous puncture of renal calyxes guided by a novel device coupled with ultrasound

ABSTRACT Purpose: To evaluate the efficiency of a novel device coupled with ultrassound for renal percutaneous puncture. Materials and Methods: After establishing hydronephrosis, ten pigs had three calyxes of each kidney punctured by the same urology resident, with and without the new device ("Punctiometer"). Time for procedure completion, number of attempts to reach the calyx, puncture precision and puncture complications were recorded in both groups and compared. Results: Puncture success on the first attempt was achieved in 25 punctures (83%) with the Punctiometer and in 13 punctures (43%) without the Punctiometer (p=0.011). The mean time required to perform three punctures in each kidney was 14.5 minutes with the Punctiometer and 22.4 minutes without the Punctiometer (p=0.025). The only complications noted were renal hematomas. In the Punctiometer group, all kidneys had small hematomas. In the no Punctiometer group 80% had small hematomas, 10% had a medium hematoma and 10% had a big hematoma. There was no difference in complications between both groups. Conclusions: The Punctiometer is an effective device to increase the likelihood of an accurate renal calyx puncture during PCNL, with a shorter time required to perform the procedure.

Predicting calyceal access for percutaneous nephrolithotomy with computed tomography multiplanar reconstruction

OBJECTIVES: Objective parameters in computed tomography (CT) scans that could predict calyceal access during percutaneous nephrolithotomy have not been evaluated. These parameters could improve access planning for percutaneous nephrolithotomy. We aimed to determine which parameters extracted from a preoperative multiplanar reconstructed CT could predict renal calyceal access during a percutaneous nephrolithotomy. METHODS: From January 2009 through April 2011, 230 patients underwent 284 percutaneous nephrolithotomies at our institution. Sixteen patients presented with complete staghorn calculi, and 11 patients (13 renal units) were analyzed. Five parameters were extracted from a preoperative reconstructed CT and compared with the surgical results of percutaneous nephrolithotomy. RESULTS: Fifty-eight calyces were studied, with an average of 4.4 calyces per procedure. A rigid nephroscope was used to access a particular calyx, and a univariate analysis showed that the entrance calyx had a smaller length (2.7 vs. 3.98 cm, p = 0.018). The particular calyx to be accessed should have a smaller length (2.22 vs. 3.19 cm, p = 0.012), larger angles (117.6 vs. 67.96, p<0.001) and larger infundibula (0.86 vs. 0.61 cm, p = 0.002). In the multivariate analysis, the only independent predictive factor for accessing a particular calyx was the angle between the entrance calyx and the calyx to be reached (OR 1.15, 95% confidence interval [CI], 1.053-1.256, p = 0.002). CONCLUSION: The angle between calyces obtained by multiplanar CT reconstruction is the only predictor of calyx access. .

Development of a computer assisted gantry system for gaining rapid and accurate calyceal access during percutaneous nephrolithotomy

PURPOSE: To design a simple, cost-effective system for gaining rapid and accurate calyceal access during percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: The design consists of a low-cost, light-weight, portable mechanical gantry with a needle guiding device. Using C-arm fluoroscopy, two images of the contrast-filled renal collecting system are obtained: at 0-degrees (perpendicular to the kidney) and 20-degrees. These images are relayed to a laptop computer containing the software and graphic user interface for selecting the targeted calyx. The software provides numerical settings for the 3 axes of the gantry, which are used to position the needle guiding device. The needle is advanced through the guide to the depth calculated by the software, thus puncturing the targeted calyx. Testing of the system was performed on 2 target types: 1) radiolucent plastic tubes the approximate size of a renal calyx (5 or 10 mm in diameter, 30 mm in length); and 2) foam-occluded, contrast-filled porcine kidneys. RESULTS: Tests using target type 1 with 10 mm diameter (n = 14) and 5 mm diameter (n = 7) tubes resulted in a 100 percent targeting success rate, with a mean procedure duration of 10 minutes. Tests using target type 2 (n = 2) were both successful, with accurate puncturing of the selected renal calyx, and a mean procedure duration of 15 minutes. CONCLUSIONS: The mechanical gantry system described in this paper is low-cost, portable, light-weight, and simple to set up and operate. C-arm fluoroscopy is limited to two images, thus reducing radiation exposure significantly. Testing of the system showed an extremely high degree of accuracy in gaining precise access to a targeted renal calyx.

Ureterocalicostomía laparoscópica como recurso técnico ante la estenosis pieloureteral recidivada / Laparoscopic ureterocalicostomy in recurrent pyelo-ureteral stenosis

Reportamos la realización exitosa de una ureterocalicostomía laparoscópica transperitoneal en una paciente con estenosis pieloureteral recidivada a distintos tratamientos quirúrgicos. Creemos que la técnica es segura y reproducible, entregando las ventajas de la cirugía mínimamente invasiva.

We report a successful laparoscopic transperitoneal ureterocalicostomy in a patient with recurrent pyelo-ureteral stenosis, who fails to different surgical treatments. We believe that this technique is safe and reproducible, bringing the benefits of minimally invasive surgery.

Cirugía percutánea de la litiasis en el divertículo calicilar / Lithiasis percutaneous surgery in calyciliar diverticulum

Presentamos nuestra serie de pacientes con litiasis en un divertículo calicilar, manejados enteramente por vía percutánea. Se realizaron 18 cirugías percutáneas de litiasis diverticular de un total de 189 cirugías percutáneas renales. Todos los divertículos tuvieron localización posterior, y el tamaño de la litiasis, en promedio, fue de 2,1 cm. Se utilizó un acceso directo al divertículo en los 18 pacientes, y en 6 se requirió un segundo acceso para la extracción de una litiasis piélica asociada. A un paciente se le realizó fulguración endoscópica del divertículo y al resto se les realizó dilatación del infundíbulo diverticular. El tiempo promedio del procedimiento fue de 1 hora, mientras que el tiempo promedio de hospitalización fue de 48 horas. A todos los pacientes se les retiró la sonda de nefrostomía a las 48 horas. No se registraron complicaciones. Todos los pacientes quedaron libres de litiasis. El manejo quirúrgico de la litiasis del divertículo calicilar puede ser realizado en la gran mayoría de casos mediante un abordaje percutáneo, logrando excelentes resultados en cuanto a ausencia de síntomas y litiasis residual, acompañado de una baja morbilidad.

Ureterocalicostomy for reconstruction of complicated ureteropelvic junction obstruction.

OBJECTIVE: To review our experience with ureterocalicostomy using the treatment of complicated ureteropelvic junction (UPJ) obstruction. MATERIAL AND METHOD: Medical records of all patients with complicated ureteropelvic junction obstruction treated by ureterocalicostomy from 1985 to 2000 were reviewed. Causes of UPJ obstruction, surgical techniques, peri-operative course and outcome were noted. RESULTS: Fifteen patients were enrolled in this study (6 males and 9 females) with the mean age of 39 years old (28-45). Twelve patients were after stone surgery, 2 were after pyeloplasty for congenital UPJ obstruction and one patient was after blunt abdominal trauma. All the procedures were done by flank incision. After excision of the lower pole, the ureter was anastomosed to the lower caliceal mucosa without tension over an internal stent. Nephrostomy tubes were used in all of the patients. The mean hospital stay was 14 days (10-20). Twelve cases (80%) were found to be successful and are still doing well with the mean follow-up time of 2.5 years (0.5-12). Three patients (20%) were found to have failed, and subsequently nephrectomy was done in one case and permanent nephrostomy was used in 2 cases due to a solitary kidney. CONCLUSION: Ureterocalicostomy is one of the options for treatment of complicated UPJ obstruction that can provide good drainage as well as excellent long term results.

Boari flap calycovesicostomy: a salvage procedure for giant hydronephrosis due to ureteropelvic junction obstruction.

The surgical management of two patients with giant hydronephrosis in a solitary kidney treated by Boari flap calycovesicostomy is presented. In one patient, this operation was done following unsuccessful previous pyeloplasty, while in the other this was done as the primary operation. Though free reflux was observed in both the cases, the refluxed contrast emptied satisfactorily after double voiding. No deterioration of renal function was noted during the follow-up period of 12 months.