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Introduction: The metal-based Resonance stent (RS) has traditionally been placed in patients with malignant ureteral obstruction; as such, the long-term utility of RS among patients with benign ureteral obstruction (BUO) remains underinvestigated. Methods: We retrospectively reviewed our database for patients with BUO who underwent RS placement between 2010 and 2020. The impact of chronic RS placement on renal function was evaluated by estimated serum creatinine-based glomerular filtration rate (eGFR), furosemide renal scan, and CT-based renal parenchymal volume measurement. The number of and reason for RS stent exchanges during the follow-up period, incidence of encrustation, and the average indwell time were recorded. A cost analysis of placing the RS vs a polymeric stent was performed. Results: Among 43 RS patients with BUO, at a mean follow-up of 26 months, there was no change in eGFR (p = 0.99), parenchymal volume (p = 0.44), or split renal function of the stent-bearing side on renal scan (p = 0.48). The mean RS indwell time was 9.7 months. Eleven patients (26%) underwent premature stent replacement (6 cases) or removal (5 cases). Stents in 9 patients (32%) were encrusted, of which 4 (44%) required laser lithotripsy. Overall, 25 patients (58%) and 12 patients (28%) had a mean stent indwell time of ≥6 months and ≥12 months, respectively. Placing an RS resulted in a 52%, 37%, and 5.6% cost reduction compared with a regular polymeric stent placement, where it was exchanged every 6, 4, or 3 months, respectively. Conclusions: RS deployment in the patient with a BUO results in cost-effective maintenance of renal function and of renal parenchymal volume at a mean follow-up of 2 years; however, only 28% of patients fulfilled the 1-year criterion for RS indwell time. [ABSTRACT FROM AUTHOR]

Introduction: Patients who form kidney stones are typically advised to limit intake of nondairy animal protein. Plant-based meat products may be a processed substitute protein source for these patients and have recently gained popularity because of health concerns, increased retail availability, decreased environmental impact, and meat supply shortages during the COVID-19 pandemic. Despite these perceived benefits and tangential association with whole food plant-based diets, the potential lithogenic risks associated with these products are not well characterized. Methods: The U.S. Department of Agriculture database was queried with a sample of plant-based meat products widely available to U.S. consumers. Nutrient profile data were compiled and compared with animal protein data using standardized serving sizes. Primary protein sources were identified using verified ingredient lists. Oxalate content was extrapolated based on dietary data sources. Results: A total 47 plant-based meat products (16 beef, 11 pork, 10 chicken, and 10 seafood) were analyzed. Compared with their respective animal protein, most products contained on average fewer calories (plant-based beef 77%, pork 94%, chicken 86%, and seafood 83%) and less protein (plant-based beef 68%, pork 96%, chicken 53%, and seafood 54%). Most products used soy protein as the primary protein source (55%). Soy-based beef contained the highest average oxalate content (18 mg per serving), whereas soy-based seafood contained the lowest (7 mg). The most common non-soy protein source was pea protein (30%), containing trace amounts of oxalate. Sodium content was higher in most plant-based products overall (72%) and in each category (plant-based beef 109%, pork 128%, chicken 100%, and seafood 148%). Calcium content was higher (plant-based beef 317%, pork 144%, chicken 291%, and seafood 295%) compared with animal protein. Conclusions: Most plant-based meat products consist of protein sources that are, relative to animal protein sources, higher in oxalate, sodium, and calcium. Stone-forming patients should be counseled about the potential lithogenic risk of these processed products. [ABSTRACT FROM AUTHOR]

Introduction: We provide primary patency rate of metallic ureteral stents in cancer patients and investigate the factors affecting primary patency. Methods: All cancer patients who had received metallic stents for malignant ureteral obstruction between July 2009 and November 2012 in our institute were included. No patients were excluded. Patient profiles, imaging studies, and laboratory data were collected. Patient profiles included age, gender, body height, body weight, body mass index, cancer types, treatment for cancer, response to cancer treatment, methods of stent insertion, and prior ordinary stents. Imaging studies included renal ultrasonography, antegrade pyelography, CT, and MRI. Laboratory data included urinalysis, urine culture, and serum creatinine. Complications were defined according to the Clavien–Dindo classification. Primary patency was defined as a complete resolution or downgrading of hydronephrosis shown by imaging studies or success in the removal of a preexisting nephrostomy tube; otherwise the procedure was considered a primary failure. The primary endpoint was the primary patency rate of the stents. The secondary endpoints were risk factors for primary stent failure. Results: A total of 124 stents were inserted into 96 patients with malignant ureteral obstruction. There were no grade 3/4 complications. The overall primary patency rate was 87.9% (109/124). In univariate analysis, antegrade insertion (OR = 24.15, p-value = 0.0086) and urinary tract cancer (OR = 4.18, p-value = 0.0164) were significantly associated with primary failure. Those with prior ordinary stents (OR = 0.20, p-value = 0.0158) or response to cancer treatment (OR = 0.25, p-value = 0.0228) were associated with stent patency. In multivariate analysis, antegrade insertion (OR = 22.04, p-value = 0.0041) and response to cancer treatment (OR = 0.15, p-value = 0.01081) remained significant factors. Conclusions: In this large cohort of cancer patients requiring urinary diversion to preserve renal function, several factors were associated with the success rate of metallic stents. [ABSTRACT FROM AUTHOR]

Background: To increase complex minimally invasive skills (MIS), frequent training outside the clinical setting is of uttermost importance. This study compares two low-cost pediatric MIS simulators, which can easily be used preclinically. Materials and Methods: The LaparoscopyBoxx is a portable simulator without a tracking system, with costs ranging from €90 to €315. The EoSim simulator has a built-in camera and tracking system and costs range from €780 to €1800. During several pediatric surgical conferences and workshops (January 2017-December 2018), participants were asked to use both simulators. Afterward, they completed a questionnaire regarding their opinion on realism and didactic value, scored on a five-point Likert scale. Results: A total of 50 participants (24 experts and 25 target group, one unknown) evaluated one or both simulators. Both simulators scored well on the questionnaire. The LaparoscopyBoxx scored significantly better regarding the "on screen representation of the instrument actions" (mean 4.2 versus 3.5, P = .001), "training tool for pediatric surgery" (mean 4.4 versus 3.9, P = .005), and "appealing take-home simulator" (mean 4.6 versus 4.0, P = .002). Conclusion: The simulators tested in this study were both regarded an appealing take-home simulator. The LaparoscopyBoxx scored significantly better than the EoSim, even though this is a low budget simulator without tracking capabilities. [ABSTRACT FROM AUTHOR]

Background: Percutaneous nephrolithotomy (PCNL) requires the urologist to have detailed knowledge of the stone and its relationship with the renal anatomy. Immersive virtual reality (iVR) provides patient-specific three-dimensional models that might be beneficial in this regard. Our objective is to present the initial experience with iVR in surgeon planning and patient preoperative education for PCNL. Materials and Methods: From 2017 to 2018 four surgeons, each of whom had varying expertise in PCNL, used iVR models to acquaint themselves with the renal anatomy before PCNL among 25 patients. iVR renderings were also viewed by patients using the same head-mounted Oculus rift display. Surgeons rated their understanding of the anatomy with CT alone and then after CT+iVR; patients also recorded their experience with iVR. To assess the impact on outcomes, the 25 iVR study patients were compared with 25 retrospective matched-paired non-iVR patients. Student's t-test was used to analyze collected data. Results: iVR improved surgeons' understanding of the optimal calix of entry and the stone's location, size, and orientation (p < 0.01). iVR altered the surgical approach in 10 (40%) cases. Patients strongly agreed that iVR improved their understanding of their stone disease and reduced their preoperative anxiety. In the retrospective matched-paired analysis, the iVR group had a statistically significant decrease in fluoroscopy time and blood loss as well as a trend toward fewer nephrostomy tracts and a higher stone-free rate. Conclusions: iVR improved urologists' understanding of the renal anatomy and altered the operative approach in 40% of cases. In addition, iVR improved patient comprehension of their surgery. Clinically, iVR had benefits with regard to decreased fluoroscopy time and less blood loss along with a trend toward fewer access tracts and higher stone-free rates. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the effects of prostatic apex shape variations on positive apical margin (PAM) rate after radical prostatectomy (RP) by undertaking a comparative study of robot-assisted laparoscopic radical prostatectomy (RALP) vs open radical prostatectomy (ORP). Patients and Methods: A total of 3324 cases of RP (1004 ORP and 2320 RALP) from January 2004 to March 2017 were retrospectively reviewed. All patients underwent preoperative MRI and the cohorts were stratified into four categories according to prostatic apical shape at the midsagittal plane. Between ORP and RALP groups, age, body mass index, preoperative prostate-specific antigen (PSA), biopsy and pathological Gleason score (GS), clinical and pathological stage, and prostatic apex shapes were compared. Logistic regression analyses were performed to evaluate significant predictors of PAM. Propensity adjustments were undertaken before statistical analysis to minimize the lack of randomization. Results: ORP and RALP groups showed no significant differences in age, body mass index, PSA, biopsy and pathological GS, clinical and pathological stage, as well as prostatic apical shape variations. The ORP group showed a PAM of 17.5% that was significantly higher than 12.3% of the RALP group ( p < 0.001). Both groups showed the highest PAM with apical type 3, which is the apex covering the posterior aspect of membranous urethra (ORP 33.9%, RALP 28.5%). In unadjusted data, multiple logistic regression analysis showed that prostate apical type 3 was a significant independent predictor of PAM, but other apex types were not. Conclusions: Prostate apical type 3 was a significant independent predictor of PAM. The RALP group showed better outcomes in terms of PAM compared with the ORP group. Preoperative MRI might be a potentially useful tool for preoperative designing of the surgical modalities. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to evaluate the efficacy and safety of a new articulating bipolar energy device, the EndoWrist® One™ Vessel Sealer (VS), in da Vinci® robot-assisted gastrectomy.Materials and Methods: Patients (n = 17) with cT1/2 gastric cancer who underwent robotic gastrectomy using the VS were prospectively enrolled in the study group (VS group). The clinicopathological outcomes, including operative time, intraoperative blood loss, amount of postoperative drainage, postoperative biochemical analysis results, and complication rates, were prospectively collected and compared with those of patients who underwent robotic gastrectomy using conventional ultrasonic shear force ([US] group, n = 52) during the same time period.Results: Although the VS provided a good direction for dissection because of the articulating function, the ancillary use of conventional bipolar coagulation was occasionally needed due to the blunt, nonactive end tip of the VS. The operative time, intraoperative blood loss, postoperative drainage, and absence of complication rates did not differ between the VS and US groups, but the C-reactive protein levels on the second postoperative day (8.06 versus 11.7, P = .002) and serum albumin levels on the fifth postoperative day (3.51 versus 3.32, P = .019) were superior in the VS group.Conclusion: Use of the VS in robotic gastrectomy was feasible and provided good configuration in the direction of dissection. The learning process for use of the VS in the initial series was relatively rapid, resulting in comparable results between the VS and US groups. Reduced inflammation and albumin loss were identified as possible benefits of the VS. [ABSTRACT FROM AUTHOR]

Purpose: To determine the incidence and predictors of major complications in patients undergoing percutaneous cryoablation (PCA) for small renal masses. Methods: We performed a retrospective analysis of patients undergoing PCA from 2005 to 2012. We analyzed demographic, radiographic, and complication data. We defined complications as any deviation from the expected postoperative course. We determined predictors of complications. Results: A total of 190 patients were included in the study. The mean age was 69 years, and 132 (69%) were males. The mean tumor diameter was 2.2 cm (0.8-4.0 cm). The mean number of probes utilized per procedure was 2.3. We observed 16 (8.4%) complications including 14 Clavien grade I, which includes 6 (2%) large renal/retroperitoneal hematomas, 4 (2%) pneumothoraxes, 2 (1%) urinary tract infections, and 2 (1%) atrial fibrillations. There were two (1%) Clavien grade II complications (intestinal perforations). In univariable analysis, larger tumors and more probes were associated with higher risk of complications (all ps < 0.05). In multivariable analysis, larger tumor dimension (odds ratio [OR] = 2.85; 95% confidence interval [CI] = 1.34, 6.05; p = 0.006) was independently associated with major complications. After multivariable adjustments for patient's characteristics such as age, gender, American Society of Anesthesiologists, year of surgery, and histopathology, larger tumor dimension (OR = 2.85; 95%CI = 1.34, 6.05; p = 0.006) and more cryoablation probes (OR = 1.94; 95%CI = 1.36, 2.75; p < 0.001) were independently associated with higher risk of major complications. Conclusions: In a cohort of patients undergoing PCA for T1a small renal mass, larger tumor dimension and more cryoablation probes were independently associated with higher risk of complication. Although PCA is relatively safe and the major complications are infrequent, careful patient selection is crucial. [ABSTRACT FROM AUTHOR]

Objective: We compared postoperative outcomes and quality of life (QoL) between patients who received a nephrostomy tube vs a ureteral stent following percutaneous nephrolithotomy (PCNL) in a prospective, double-blind, randomized manner. Materials and Methods: Between September 2015 and March 2016, we randomized 30 patients undergoing PCNL to receive nephrostomy drainage (Group 1: 8F or 10F) or Double-J ureteral stent (Group 2) at conclusion of surgery. Nephrostomy tubes were removed within 48 hours (before discharge) and ureteral stents were removed at least 2 weeks after surgery. Patients' QoL was assessed with the Wisconsin StoneQOL questionnaire preoperatively and then 7 to 10 days and 30 days following surgery. Inclusion criteria included an uncomplicated procedure, normal preoperative renal function, and clinically insignificant residual stone fragments on postoperative imaging. We calculated the preoperative and postoperative QoL score difference between the two groups. We also evaluated perioperative characteristics, inpatient analgesic requirements, length of stay (LOS), and postsurgical complications. Outcome: Patient characteristics between Groups 1 and 2 were comparable with similar age (58.3 vs 54.7, p = 0.534), gender ratio, and stone burden (276.6 mm2 vs 259 mm2, p = 0.84) and composition. There was no significant difference between perioperative outcomes, including stone-free rate (93.3% vs 86.7%), operative times (125.7 minutes vs 115 minutes, p = 0.29), estimated blood loss (103.3 mL vs 100.7 mL, p = 0.9), LOS (3.2 days vs 1.9 days, p = 0.1), and complications (2 in each group). Inpatient analgesic requirements were also the same (both 21.1 mg, p = 1.0). Assessment of QoL using the Wisconsin StoneQOL questionnaire showed significant differences between preoperative and postoperative health-related QoL in 18 of the 28-question instrument at 7 to 10 days. Patients in Group 2 had significantly worse QoL change and a multitude of negative responses on the StoneQOL assessment, not only those commonly associated with stent irritation. Eighty percent of participants in Group 2 also attributed their complaints to having a stent placed. Both groups had similar QoL status at 30 days after surgery. Conclusion: Despite the literature advocating 'tubeless' PCNL with ureteral stent placement at conclusion of surgery, our randomized prospective study shows that QoL is significantly worse with stent placement than with temporary nephrostomy drainage in the immediate aftermath following PCNL, using a validated QoL assessment instrument specific for nephrolithiasis. [ABSTRACT FROM AUTHOR]

Introduction: Traditional techniques for obtaining percutaneous renal access utilize continuous fluoroscopy. In an attempt to minimize radiation exposure, we describe a novel laser direct alignment radiation reduction technique (DARRT) for percutaneous access and test it in a bench-top model. Methods: In this randomized-controlled bench-top study, 20 medical personnel obtained renal accesses using both the conventional bullseye technique and the laser DARRT. The primary endpoint was total fluoroscopy time. Secondary endpoints included insertion time, puncture attempts, course corrections, and subjective procedural difficulty. In the laser DARRT, fluoroscopy was used with the C-arm positioned with the laser beam at a 30° angle. The access needle and hub were aligned with the laser beam. Effective caliceal puncture was confirmed with fluoroscopy and direct vision. The Paired samples Wilcoxon signed rank test was used for statistical analysis with significance at p < 0.05. Results: A total of 120 needle placements were recorded. Fluoroscopy time for needle access using the laser DARRT was significantly lower than the bullseye technique in all groups as follows: attendings (7.09 vs 18.51 seconds; p < 0.001), residents (6.55 vs 13.93 seconds; p = 0.001), and medical students (6.69 vs 20.22 seconds; p < 0.001). Students rated the laser DARRT easier to use (2.56 vs 4.89; p < 0.001). No difference was seen in total access time, puncture attempts, or course corrections between techniques. Conclusion: The laser DARRT reduced fluoroscopy time by 63%, compared with the conventional bullseye technique. The least experienced users found the laser DARRT significantly easier to learn. This novel technique is promising and merits additional testing in animal and human models. [ABSTRACT FROM AUTHOR]

The safety guidewire has been an integral tool in endourologic percutaneous and ureteroscopic procedures for the last three decades, providing access to the collecting system or ureter in the event of loss of renal contact or ureteral perforation, respectively. However, recent advances in endourologic techniques and instrumentation have obviated the need of routine safety guidewire placement. Today the establishment of a ''through-and-through'' flank to urethral meatus guidewire eliminates the need of an additional guidewire during percutaneous procedures. Likewise, the availability of smaller flexible ureteroscopes, as well as modern ureteral access sheaths, has reduced the necessity of safety guidewire placement in ureteroscopic procedures. Herein, we trace the historical development of the safety guidewire concept, review recent advances in technologies that have obsoleted the safety guidewire, and evaluate recent data suggesting that continued use of a safety guidewire during ureteroscopic procedures may indeed be counterproductive. [ABSTRACT FROM AUTHOR]

Purpose: Ureteral stent-related pain is a well-known side effect of stent placement. To date, there is a paucity of resources that address this topic. Herein, we present theories on stent pain pathophysiology, summarize available pain outcome data for different stent designs, and provide an overview of the management of stent pain, including preplacement modifiers, medical management, and other considerations. Materials and Methods: This narrative review focused primarily on articles indexed in the PubMed®, Google Scholar™, and EMBASE databases. No formal search strategy was used and no meta-analysis of data was performed. Results: Stent pain pathophysiology is multifactorial and likely a result of mucosal irritation along with retrograde reflux of urine. While there is a consensus on the lack of association between stent length, diameter, and stent-related flank pain, stents should be properly sized so as to prevent dislodgement. Insufficient data exist comparing stent materials and durometry. Multiple drug-eluting stents are in development and have demonstrated promising early results. Alpha-blockers have shown efficacious results and should be considered along with or in combination with anticholinergics and nonsteroidal anti-inflammatory drugs (NSAIDs) in the treatment of ureteral stent-related symptoms, with judicious consideration of their side effect profiles. Periur-eteral botulinum toxin A injections are a promising, novel treatment modality. Conclusions: Ureteral stent pain is common and multiple modalities have been studied and are in clinical use for its treatment. Care should be taken to avoid placement of stents if possible, with continual reassessment of indications to maintain stents in patients. Relative heterogeneity among studies and small sample sizes make creating specific evidence-based pain management recommendations challenging. Alpha-blockers, antimuscarinics, and NSAIDs are all generally well tolerated and effectively reduce symptoms, but patient-specific factors must be the paramount consideration when choosing monotherapy or combination therapy. Future studies are needed to better define ideal material characteristics and pharmacologic treatments. [ABSTRACT FROM AUTHOR]

Objective: To assess the feasibility and safety of a modified retroperitoneoscopic technique in supine position for the primary tumors located below the level of renal pedicle. Materials and Methods: In this retrospective study, 27 patients with primary retroperitoneal tumors located below the level of renal pedicle were recruited from January 2009 till now. The mean age of patients was 49.0 years (36-66 years). The average body mass index was 21.1 ± 1.4kg/m². The retroperitoneoscopic resections were performed in supine position for all patients. The perioperative outcomes were collected and analyzed. Results: All cases were performed by the modified technique without converting to open surgery. The mean operation time was 98.3 ± 12.8 min, with a mean estimated blood loss of 94.4 ± 42.5 mL. There were four patients suffering from intraoperative complications, one with the inferior vena cava (IVC) injury, one with the lumbar vein injury, and other two with the peritoneum breach. Postoperatively, the median bowel recovery time was 2 days (range: 1-3 days), and the mean length of stay after operation was 2.9 ± 1.0 days. Additionally, compared with the tumors located around the aorta (region B), a longer operation time was needed with tumors located around the IVC (region A) (A vs B: 105.8 ± 10.2 vs 91.2 ± 14.4, p = 0.02). Histopathology confirmed paraganglioma in 5 cases, schwannoma in 10 cases, and ganglioneuroma in 12 cases. After follow-up of 12-72 months, no recurrences have been identified. Conclusion: Our modified retroperitoneoscopic technique in supine position was proven to be safe and effective for the treatment of primary retroperitoneal tumors, especially suitable for the tumors located below the level of the renal pedicle. [ABSTRACT FROM AUTHOR]

Background and Purpose: Endoureterotomy is a viable option for treating patients with benign ureteral stricture. We compared the efficacy and safety of double versus single ureteral stent placement after laser endoureterotomy. Patients and Methods: This study included 55 patients with benign ureteral strictures; all patients underwent retrograde laser endoureterotomy. Patients were randomized either to single or double ureteral stents. Single stents were placed in 27 ureters while double stents were placed in 28 ureters. The stent diameter used was 7 F, and stents were indwelling for 8 weeks. Imaging was performed 1 month after stent removal and repeated regularly every 3 months. Clinical characteristics, operative results, and functional outcomes were compared for strictures managed in both groups. Success was evaluated both subjectively and objectively. Results: Fifty-five patients with a mean age of 46 (16-75) years had benign ureteral strictures; the mean stricture length was 1.92 (1-3) cm. The mean follow-up was 25.7 (9-42) months. The overall success rate was 67.3% (37 patients) with no radiologic evidence of obstruction, 6 (10.9%) patients showed symptomatic improvement while 12 (21.8%) patients underwent surgical reconstruction. Success was significantly higher for ureteral strictures (>1.5 cm) managed with double stent placement (82.4%), compared with single stent placement (38.9%) with a P value of 0.009. Conclusions: Double stent placement of the ureter after laser endoureterotomy achieved a higher success rate compared with single stent placement in cases of benign ureteral strictures. Although ureteral strictures (≤1.5 cm) achieved better outcome after laser endoureterotomy, strictures (>1.5 cm) favored better with double stent versus single stent placement. [ABSTRACT FROM AUTHOR]

Background and Purpose: Flexible nephroscopy is an important technique in the management of staghorn renal calculi to reach peripheral calices. In this study, we present our experience with flexible nephroscopy and fluoroscopy-guided additional access creation for staghorn renal calculi. Patients and Methods: We conducted a retrospective analysis of patients with staghorn renal calculi who were treated with multiple percutaneous renal tracts created with the guidance of flexible nephroscopy and fluoroscopy. Additional tracts were performed with combined flexible nephroscopy and fluoroscopy guidance. Flexible nephroscopy was used to help target the calix and ensure the safety of access. Results: Additional percutaneous renal access was achieved using combined flexible nephroscopy and fluoroscopy guidance in 26 patients with complete staghorn ( n=21) and partial staghorn ( n=5) kidney stones. The cumulative stone size was 59.3 mm. The mean procedure times, fluoroscopy times, and hospitalization times were 91.5 minutes, 3.4 minutes, and 2.7 days, respectively. The postoperative hematocrit drop was 4.96±3.8. Upper and lower calices were the most common primary access tracts in 11 and 15 patients, respectively. Stone-free status was achieved in 22 (84.6%) patients with a mean 2.1±0.3 tract number. Postoperative complications were observed in six (23.1%) patients. Conclusions: In the requirement of additional access for staghorn renal calculi, use of flexible nephroscopy with fluoroscopy increases the safety of the procedure by confirmation of precise renal access. [ABSTRACT FROM AUTHOR]

Introduction: Several clinical series of retrograde nephrostomy for percutaneous nephrolithotomy (PCNL) have been published over the past 30 years demonstrating good outcomes and safety. We previously reported our adaptation of the Lawson technique, wherein we deploy the puncture wire through a flexible ureteroscope. We herein aim to clarify the performance characteristics of this nephrostomy creation technique. Materials and Methods: Institutional Review Board approval and informed consent were obtained. A ureteroscopy-assisted retrograde nephrostomy (UARN) procedure was performed as described previously. Data were collected prospectively. Multiple patient and operative factors were evaluated for association with UARN success and nephrostomy creation time: body mass index (BMI), skin-to-stone distance, Guy's score, Clinical Research of the Endourological Society nephrolithometric score, hydronephrosis, stone burden, location of nephrostomy, exit from a stone-bearing calix, and use of holmium laser to access calix. Results: Nephrostomy was successful in 49/52 UARN procedures (94%). Only single access was placed: upper-18, mid-27, and lower-7. Median BMI was 29 kg/m2 and median time for nephrostomy creation was 39 minutes. Fluoroscopy time for the entire PCNL including nephrostomy creation was 84 and 16 seconds for case numbers 1-25 and 26-52, respectively. By stepwise linear regression, variables correlating with nephrostomy creation time were BMI ( r2=0.219), stone burden ( r2=0.094), use of holmium laser to access calix ( r2=0.104), and total r2 linear=0.416. Conclusions: UARN is an intuitive safe procedure that offers dramatic reductions in fluoroscopy times. UARN is best suited to cases requiring only one nephrostomy tract. Upper pole access is commonly performed with a subcostal technique to navigate the puncture wire below the ribs. Increasing BMI best predicts longer nephrostomy creation times; procedure failure was associated with BMI exceeding 40 kg/m2. UARN is a robust technique for nephrostomy creation in appropriately selected patients. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the impact of maximal urethral length preservation (MULP) technique in comparison with posterior urethral reconstruction and anterior bladder suspension (PRAS) technique on the continence rates (CR), time to achieve continence among patients with prostate cancer (PCa) undergoing robot-assisted laparoscopic prostatectomy (RALP). Patients and Methods: We prospectively analyzed the CR, time to achieve continence, pre- and postoperative prostate-specific antigen (PSA) levels, rates of positive margins among three groups of continent men with PCa undergoing RALP from whom consent was obtained. Each group consisted of 30 patients: PRAS was performed in group A, combined MULP and PRAS in group B, and MULP in group C. Continence was measured by patient self-reporting of the number of pads/24 h. Results: No differences were detected in the age, preoperative PSA levels, biochemical recurrence, prostate volume, and positive margins for the three groups. Men in groups B and C had marked improvement in CR 1, 3, and 6 months after catheter removal vs group A (50% and 70% vs 10%, 90% and 96.66% vs 23.3% and 100%, 100% vs 53.3%, respectively, P<0.0001). The average and median times to continence were significantly shorter in group B (5.4 and 4 weeks) and C (3.8 and 3 weeks) vs group A (27.4 and 22.5 weeks), P<0.00001. Using Cox regression analysis, only MULP and MULP+PRAS techniques were significantly correlated with continence outcomes 1, 3, and 6 months after catheter removal. Conclusions: MULP rather than PRAS confers higher postoperative CR and shorter time to achieve continence among patients with PCa who underwent RALP without increasing risk of positive margin. [ABSTRACT FROM AUTHOR]

Purpose: To provide clinical outcomes of the Resonance metallic ureteral stent in patients with malignant ureteral obstruction, as well as clinical factors predicting stent failure. Methods: Cancer patients who have received Resonance stents from July 2009 to March 2012 for ureteral obstruction were included for chart review. Stent failure was detected by clinical symptoms, image studies, and renal function tests. Survival analysis for stent duration was used to estimate patency rate and factors predicting stent failure. Results: A total of 117 stents were inserted successfully into 94 ureteral units in 79 patients. There were no major complications. These stents underwent survival analysis and proportional hazard regression. The median duration for the stents was 5.77 months. In multivariate analysis, age ( P=0.043), preoperative serum creatinine level ( P=0.0174), and cancer type ( P=0.0494) were significant factors associated with stent failure. Cancer treatment before and after stent insertion had no effect on stent duration. Conclusions: Resonance stents are effective and safe in relieving malignant ureteral obstructions. Old age and high serum creatinine level are predictors for stent failure. Stents in patients with lower gastrointestinal cancers have longer functional duration. [ABSTRACT FROM AUTHOR]

Background and Purpose: Recent advances in distal sensor technologies have made distal sensor ureteroscopes both commercially and technically feasible. We evaluated performance characteristics and optics of a new generation distal sensor Flex-XC (XC) and a standard flexible fiberoptic ureteroscope Flex-X² (X²), both from Karl Storz, Tuttlingen, Germany. Materials and Methods: The ureteroscopes were compared for active deflection, irrigation flow, and optical characteristics. Each ureteroscope was evaluated with an empty working channel and with various accessories. Optical characteristics (resolution, grayscale imaging, and color representation) were measured using United States Air Force test targets. We digitally recorded a renal porcine ureteroscopy and laser ablation of a stone with the X² and with the XC. Edited footage of the recorded procedure was shown to different expert surgeons (n = 8) on a high-definition monitor for evaluation by questionnaire for image quality and performance. Results: The XC had a higher resolution than the X² at 20 and 10 mm 3.17 lines/mm vs 1.41 lines/mm, 10.1 vs 3.56, respectively (P = 0.003, P = 0.002). Color representation was better in the XC. There was no difference in contrast quality between the two ureteroscopes. For each individual ureteroscope, the upward deflection was greater than the downward deflection both with and without accessories. When compared with the X², the XC manifested superior deflection and flow (P < 0.0005, P < 0.05) with and without accessory present in the working channel. Observers deemed the distal sensor ureteroscope superior in visualization in clear and bloody fields, as well as for illumination (P = 0.0005, P = 0.002, P = 0.0125). Conclusions: In this in vitro and porcine evaluation, the distal sensor ureteroscope provided significantly improved resolution, color representation, and visualization in the upper urinary tract compared with a standard fiberoptic ureteroscope. The overall deflection was also better in the XC, and deflection as well as flow rate was less impaired by the various accessories. [ABSTRACT FROM AUTHOR]

Introduction: Malignant ureteral obstruction (MUO) has traditionally been a difficult problem to manage. Indwelling ureteral stents have a failure rate up to 50%, necessitating the placement of percutaneous nephrostomy (PCN) drainage, which has associated complications and impacts on quality of life. Recently, metallic ureteral stents have emerged as a treatment for extrinsic ureteral obstruction. We present our initial experience using Resonance (Cook Urologic, Spencer, IN) full-length metallic stents for MUO. Materials and Methods: 20 patients (27 renal units) with advanced cancers and MUO were treated with metallic stents. Patients were followed prospectively to evaluate for recurrent obstruction. Perioperative morbidity and overall mortality were recorded. Results: The mean patient age was 49.9 years (SD 18.9). The primary malignancies causing MUO were gastrointestinal (8), gynecologic (6), genitourinary (2), or other (4). All but two renal units had been previously treated with traditional stents. Eight out of 20 (40%) patients required further intervention for their MUO. Mean time to failure for the metallic stents was 7.4 months (222 days). Two patients required conversion to percutaneous drainage. Five patients required change to traditional stents (3) or removal of metallic stents. At the last follow-up, sixteen patients had died. Fourteen of the sixteen patients died with functioning metallic stents in place, although one patient who initially had bilateral metallic stent placements had a left stent removed due to migration. Of the remaining four living patients, two have functioning metallic stents at a mean follow-up of 42 months. Discussion: MUO remains a difficult clinical problem in a group of patients with a high mortality. While metallic stents ultimately have a failure rate similar to that of traditional stents, the mean time to failure is longer. Therefore, metallic stents may benefit patients with MUO, because the longer dwell time may eliminate the need for more frequent stent changes or further interventions. [ABSTRACT FROM AUTHOR]

Purpose: To describe a novel technique to control dorsal vein complex (DVC) during robot-assisted radical prostatectomy (RARP). Patients and Methods: We have been using a laparoscopic bulldog clamp to control DVC before apical dissection and urethral division. Data of 50 patients who underwent DVC control with laparoscopic bulldog clamp (group 1) were retrospectively compared with 50 consecutive patients in whom DVC was controlled with suture ligation (group 2). In the bulldog and suture groups, 30 and 31 patients underwent concomitant bilateral extended pelvic lymph node dissection (PLND), respectively. Operative and anastomosis time, estimated blood loss (EBL), apical surgical margin positivity, and early continence rates were evaluated. Results: Patients in the bulldog group had significantly shorter operative time compared with patients in the suture group (146.8 vs 178.4 min, P=0.0005). Anastomosis time was significantly shorter in the bulldog group (12.3 vs 15.5 min, P=0.002). There was no difference in EBL between the groups (185 vs 184.2 mL). Immediate, postoperative first and third month continence rates were 62% vs 44%, 74% vs 60%, 90% vs 74% in groups 1 and 2, respectively. Although continence rates were better in favor of the bulldog group at each evaluation period, the difference did not reach statistical difference. None of the patients in both groups had apical surgical margin positivity. Conclusions: The use of a laparoscopic bulldog clamp to control DVC was associated with shorter operation and anastomosis time and a trend toward quicker recovery of continence. This technique provides clear vision during apical dissection and urethral division while potentially minimizing the external sphincteric trauma. Prospective randomized trials are needed for better evaluation of this technique. [ABSTRACT FROM AUTHOR]

Optimal control of the dorsal venous complex (DVC) is a critical step in robot-assisted radical prostatectomy (RARP). If DVC is not controlled properly, bleeding may occur during the apical dissection. On the other hand, if it is controlled well, a bloodless field is attained and, thus, a precise apical dissection and urethral division is possible. Suture ligation is the most common technique used for dorsal vein control, while some authors recommend using an endovascular stapler. Recently, athermal division and selective suture ligation technique has been reported for DVC control. We describe a new technique: Use of a bulldog clamp to control the DVC during RARP. The control of the DVC with a bulldog clamp allows a bloodless field with precise apical dissection and provides preservation of maximum urethral length while avoiding sphincteral injury. [ABSTRACT FROM AUTHOR]

We describe flexible ureteroscopy-directed retrograde nephrostomy access using a puncture wire to achieve renal access. This is a natural extension of modern retrograde intrarenal surgical techniques and a modernization of the original Lawson technique for retrograde nephrostomy tract creation. In appropriately selected patients, this approach is safe and permits reduced radiation exposure. We believe this technique is easy to learn and may overcome the difficult learning curve of antegrade nephrostomy techniques faced by urologists who have not undergone subspecialty training in endourology. [ABSTRACT FROM AUTHOR]

Background and Purpose: The metallic ureteral stent was first developed for patients with ureteral obstruction related to malignant disease, but it can be used in all patients needing chronic indwelling ureteral stents, including those with benign disease. The traditional method of polymer stent management often necessitates multiple exchanges per year depending on patient and logistical factors. This has significant direct financial cost and likely a negative effect on patients' overall health. The objective was to analyze and compare the costs associated with chronic indwelling metal and silicone-based ureteral stents. Patients and Methods : A prospective database of patients undergoing metal stent placement from February 2008 to June 2010 was reviewed. Mean charges for a single traditional nonmetal and metal stent insertion were calculated. Charges were based on direct hospital charges related to stent cost and surgery. Cost data were based on the fiscal year 2010 cost for polymer or metal stent insertions. Results: Twenty-one patients underwent metal stent placement at our institution. Of these, three traditional stent placements were omitted from analysis because of bundled charges for ureteroscopy at the same setting. Mean charges per single traditional and metal stent placement were $6072.75 and $9469.50, respectively. The estimated annual charges for traditional stents (3-6 exchanges) would be $18,218.25 to $36,436.50. Compared with metal stents, this is a potential financial savings of 48% to 74%. The mean direct cost to patients was 21.6% and 25.4% of the charges for metal and polymer stents, respectively. No patient needed early discontinuation of his or her metal stent because of lower urinatry tract symptoms or gross hematuria. Conclusions: Metal stents are well tolerated by patients with ureteral obstruction of various etiologies and provide a significant financial benefit compared with polymer ureteral stents. For patients who are not fit for surgical intervention regarding their ureteral occlusive disease, the metal Resonance stent is a financially advantageous and well-tolerated option. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this randomized in-vitro study was to compare the suturation time, integrity, and quality of the bladder closure in fresh cadaver pig bladders performed with barbed polyglyconate sutures vs polyglactin 910 sutures in running and interrupted fashion. Materials and Methods: Forty-eight pig bladders, each weighing from 120 to 150 g, were randomly divided into three groups: Group 1 (interrupted polyglactin 910 suture group), group 2 (running polyglactin 910 suture group), and group 3 (running barbed polyglyconate suture group). The bladder defects were closed laparoscopically, and the suturation times were noted. Two surgeons evaluated the integrity of each bladder closure. A cystometry was performed, and the filling and leak pressures were noted. A Kruskal-Wallis variance analysis test was used to compare the results of the three groups, and P<0.05 was considered significant. Results: There was a statistically significant difference between the mean suturation times of three groups: Group 1, 15.2 minutes; group 2, 9.14 minutes; and group 3, 7.13 minutes ( P<0.05). Mean bladder capacity at the time of leakage was 276.2, 353.8, and 419.7 mL for groups 1, 2, and 3, respectively, and the difference was statistically significant ( P<0.05). Conclusion: For the first time, we demonstrated laparoscopic knotless closure of bladder defects using the barbed polyglyconate suture material in an experimental in-vitro model. Closing the pig bladder with running knotless barbed suture provides a more effective and faster watertight bladder closure than traditional polyglactin 910 suture material. [ABSTRACT FROM AUTHOR]

Background and Purpose: Extrinsic ureteral compression challenges a ureteral stent's ability to facilitate urinary drainage and to protect the kidney. Our purpose was to evaluate the performance of new metallic coil-based ureteral stents in terms of tensile strength and radial compression force. Materials and Methods: Three stent designs tested from Prosurg Inc included Passage 7.0F, Snake 6.0F, and Snake 7.0F with the straight section covered with a biocompatible polymer tubing. A MTS Microbionix Testing System using Testworks II software, vibration isolation table, and a 5-N load cell were used to measure tensile and compressive strength. Stents were placed in hydraulic grips and stretched at a rate of 5 mm/s for 1 second under uniaxial tension. Extrinsic compression was exerted in 0.1-mm increments to maximum compression. The Young Modulus, E, was calculated from each trial using engineering stress. Data were analyzed using Mann-Whitney and t tests. Results: The Passage, Snake 6F, and Snake 7F stents had tensile strengths of 27±3, 5±0.1, and 73±26 kPa, respectively. Mann-Whitney tests show statistically significant difference between stents ( P<0.05). Elastic modulus needed to cause extrinsic compression was highest for Snake 6F (145,842±14332 Pa) compared with that of Passage (124,999±3182 Pa) and Snake 7F (126,132±19316 Pa), ( P<0.05). Conclusion: The Snake 6F stent had the lowest tensile strength and was least resistant to extrinsic compression. The Snake 7F had the highest tensile strength and was most resistant to extrinsic compression. All three stents are more resistant to extrinsic compression than the Applied Silhouette or Cook Resonance, yet have lower tensile strengths. [ABSTRACT FROM AUTHOR]

Despite stage migration to more organ-confined disease in the era of prostate-specific antigen, the complications of advanced prostate cancer are still relatively common. Urinary tract obstruction in advanced and metastatic prostate cancer can have a varied presentation, because it may occur in multiple anatomic locations at any point in the natural history of the disease. In all cases, management depends on the current stage of disease, technical feasibility of potential therapeutic interventions, and overall prognosis of the patient. This review highlights a practical approach to the evaluation, diagnosis, and management of obstructive uropathy from prostate cancer. [ABSTRACT FROM AUTHOR]

AbstractIntroduction:Recent advances in endoscope design have placed the charged coupled device chip on the tip of the endoscope. The image is instantly digitalized and converted into an electrical signal for transmission. Digital technology was first introduced into flexible cystoscopes/nephroscopes and subsequently into rigid and flexible ureteroscopes. Herein, we assess the image characteristics and advantages of a new generation of digital flexible ureteroscopes.Methods:The Olympus URF-V flexible digital ureteroscope and the Olympus URF-P3 fiberoptic ureteroscope were assessed in vitrofor image resolution, distortion, color representation, grayscale imaging, field of view, and depth of field.Results:The digital ureteroscope had a higher resolution at 3, 5, 10, and 20 mm (25.2 lines/mm vs. 8.0, 14.1 vs. 5.0, 6.3 vs. 2.8, and 3.2 vs. 1.3), respectively. Distortion with the digital flexible ureteroscope was lower, though not statistically significant. Color representation was better with the digital ureteroscope, whereas contrast evaluation was comparable between both scopes. The digital flexlible ureteroscope produced a 5.3 times larger image size compared with the standard fiberoptic flexible uretersocpe with a narrower field of view. The depth of field was limited by light and not the optic or the camera for both ureteroscopes.Conclusions:The development of digital flexible ureteroscopes represents a significant technological advance in urology. These devices offer significantly improved resolution and color reproduction as compared with traditional fiberoptic flexible ureteroscopes. Future clinical trials are warranted to ultimately determine the advantages of these innovative endoscopes. [ABSTRACT FROM AUTHOR]

AbstractIntroduction:The prone position has been considered the only position for percutaneous access to the kidney for the past 25 years, whereas the supine Valdivia position has recently started to gain acceptance, although it was originally described in the late 1980s. Even more recently, the Galdakao-modified supine Valdivia position was described. However, there is no consensus on which is the best position for percutaneous nephrolithotomy, and the choice is currently based on the surgeon's preference.Materials and Methods:The prone, supine, and modified supine positions are described, pointing out the advantages, disadvantages, and results of each technique.Results:A number of potential advantages have been described for the supine over the prone position: less cardiovascular change; no need for patient repositioning (with less associated risk of central and peripheral nervous system injury); less X-ray exposure to the surgeon; and less risk of colonic injury. The recently described Galdakao-modified supine Valdivia position allows for a simultaneous anterograde and retrograde approach to the renal cavities for the one-stage treatment of complex renal stones or concurrent renal and ureteral calculi. Moreover, the use of a flexible ureteroscope allows for Endovision puncture to achieve perfect access to the kidney.Conclusions:The prone position still represents the standard for percutaneous access to the kidney, and other positions should be compared with this position. However, the supine and the modified supine positions have potentially important advantages for both patients and surgeons that need to be investigated in a large randomised trial to define their superiority over the traditional prone position. [ABSTRACT FROM AUTHOR]

AbstractBackground and Purpose:Caliceal diverticula are rare congenital abnormalities that can become symptomatic if associated with a calculus or infection. We review percutaneous management of caliceal diverticula.Methods:Pathogenesis, clinical evaluation, management options, and recommended follow-up for symptomatic caliceal diverticula are reviewed. We present our single-stage and prepercutaneous nephrolithotomy opacification techniques for the management of caliceal diverticula. This involves complete extraction of all stone particles and ablation of the diverticular cavity without infundibular identification or dilation. Comparison of outcomes between our current ablative technique and our previous dilation technique is evaluated.Results:Percutaneous management of caliceal diverticula offers the highest symptomatic relief and stone-free rate of available management options. We identified 106 patients with caliceal diverticula who were treated with a percutaneous approach. Review of 85 of these patients demonstrated that most procedures can be performed with a small nephrostomy tube in place for 24 hours and an overnight hospital stay. Minimal complication and stone recurrence rates were observed. Patients treated with caliceal diverticular ablation experienced a shorter hospital stay, fewer complications, and a higher stone-free status than those patients who were treated with dilation of the diverticular infundibulum.Conclusions:Percutaneous management of caliceal diverticula using cavity ablation is a minimally invasive technique that offers long-term symptomatic relief with minimal complications. [ABSTRACT FROM AUTHOR]

AbstractTubeless percutaneous nephrolithotomy (PCNL) is a viable option for selected patients, particularly those with solitary calculi, multiple stones located in a single location, or those that can be accessed using one access tract. Benefits over the standard PCNL include reduced hospital stay, decreased pain, and decreased urine leak from the access site that would typically occur from around the nephrostomy tube. Hemostatic agents in the form of fibrin “glue” or gelatin matrix substances have been demonstrated to be safe and effective to augment the tubeless procedure. The most appropriate sealant agent available is yet to be determined. We present a review of the contemporary literature on the use of hemostatic agents for tubeless PCNL. [ABSTRACT FROM AUTHOR]

AbstractObjective:To evaluate the clinical therapeutic effects of retroperitoneal laparoscopic radical nephrectomy for T1 renal cell carcinoma (RCC).Methods:A total of 352 patients with T1 RCC underwent radical nephrectomy in our study, and they were randomly divided into two groups, including 185 cases of retroperitoneal laparoscopic radical nephrectomy and 167 cases of open radical nephrectomy through an extraperitoneal 11th rib flank incision. All operations were performed by the same platoon doctors. There were no statistically significant differences in age, sex ratio, tumor stage, and serum creatinine between the two groups. The operation time, blood loss during operation, hospital stay, and postoperative complications were analyzed and compared. All cases were followed up for 25 ± 4 months (6–42 months) and the survival rates, wound healing, and carcinoma metastasis were recorded.Results:The operation time in retroperitoneal laparoscopic radical nephrectomy group versus open radical nephrectomy was 75.6 ± 11.2 min (55–130 min) versus 68 ± 10.6 min (50–140 min), without statistically significant difference (p> 0.05). The blood loss was 110.6 ± 32.3 mL (50–1200 mL) versus 160.8 ± 38.1 mL (50–1500 mL), with statistically significant difference (p< 0.05); narcotic was required in 8 cases versus 132 cases between the two groups (p< 0.05); the fasting period was 1.3 ± 0.5 days (1–2 days) versus 2.9 ± 1.2 days (2–5 days), and hospital stay was 4.6 ± 1.2 days (3–7 days) versus 8.9 ± 1.6 days (7–14 days), with statistically significant differences (p< 0.05).Conclusions:Compared with open radical nephrectomy, retroperitoneal laparoscopic radical nephrectomy is associated with less blood loss, narcotic requirement, and complications; shorter hospital stay; and earlier resumption of routine activities. Therefore, retroperitoneal laparoscopic radical nephrectomy is a better therapy for T1 RCC. [ABSTRACT FROM AUTHOR]

AbstractPurpose:To report the outcomes of patients with ureteroenteric strictures after ileal conduit urinary diversion that were managed with Resonance®metallic ureteral stents.Patients and Methods:Ten ureteroenteric strictures in patients with ileal conduits that were managed with metallic ureteral stenting were retrospectively identified. Charts were examined for patient age, anastomosis type, stricture cause, stricture laterality, complications, and follow-up.Results:Nine of 10 (90%) cases resulted in distal stent migration. Mean time to stent migration was 21 days (range 3–60 d).Conclusions:Placement of Resonance®metallic stents in patients with ileal conduits is ineffective for management of ureteroenteric strictures because of the high rate of distal migration. [ABSTRACT FROM AUTHOR]

Background and PurposeThere have been several reports of rhabdomyolysis occurring after prolonged laparoscopic procedures in the flank position. Accordingly, we evaluated interface pressures between the skin and three commonly used operating room table surfaces. The aim of our study was to determine if pressure changes could be related to body mass index (BMI), sex, position, andor the table surface material.Patients and MethodsTen men and 10 women were grouped according to BMI <25 or ≥25, with five participants in each group. Subjects were placed in the left lateral decubitus position with the operating table flat, half flexed, fully flexed, half flexed with the kidney rest elevated, and fully flexed with the kidney rest elevated. Interface pressures were recorded, using an X-Sensor pressure sensing mat, for 5-minute periods in each of the described positions on each surface.ResultsSex and BMI were statistically significant predictors of increased pressures (P 0.0042 and 0.0402, respectively). The parameter estimate for the difference between men and women was 4.63 mm Hg (P 0.0002), and the difference for BMI ≥ 25 compared with <25 was also significant (P< 0.0209). Full table flexion (50-degree) produced significantly higher pressures than both flat (P 0.0001) and the half-flexed (25-degree) position (P< 0.0001). Positions with the kidney rest elevated were associated with significantly higher pressures than without elevation (P< 0.0001). With regard to the surface used, egg crate provided lower pressures than gel pads (P 0.0117).ConclusionWomen have significantly lower interface pressures when compared with men. BMI ≥ 25 also increases interface pressures. The use of the kidney rest is associated with markedly increased pressure; use of a half-flexed position is preferable to a full-flexed position. These data have implications for patient positioning and identification of persons at risk for rhabdomyolysis during laparoscopic renal surgery. [ABSTRACT FROM AUTHOR]

PurposeWe evaluated factors that impact the ability to learn hand-assisted laparoscopic donor nephrectomy (HALDN) to identify impediments to diffusion of this procedure.MethodsFrom February 2002 to June 2004, we collected data from our institutional database on 70 patients who underwent HALDN. Time for individual steps of the procedure (colon mobilization, kidneyureter mobilization, renal vein tributary dissection, renal hilum dissection, removal of the kidney, and overall time) were recorded. The impact of patient factors on surgical times was assessed using a general linear model. The impact of individual operative steps on overall operative time was assessed using Pearson correlation. The influence of case experience and training level were evaluated graphically and in a multivariable model.ResultsA total of 13 residents, 2 fellows, and 1 attending surgeon participated in procedures for 70 patients. Body mass index (P 0.03) and male sex (P 0.04) prolonged operative times. Colon mobilization and hilar dissection were most correlated with overall operative time. While experience improved operative times for several steps, level of training appeared more likely to influence the time for individual operative steps.ConclusionsImpediments to learning HALDN include patient factors, level of training, and particular surgical steps. Repeated exposure at increasing levels of training may improve diffusion of laparoscopic nephrectomy among urologists. [ABSTRACT FROM AUTHOR]

Image-guided percutaneous renal access for placement of an access sheath for percutaneous nephrolithotomy can be a challenging procedure, especially in patients with nondilated collecting systems, obstructed infundibula (stones or stricture), or extreme body habitus. We describe our experience using ureteroscopy along with a zero-tip stone basket to facilitate a through-and-through (percutaneous–urethra) access to the collecting system. [ABSTRACT FROM AUTHOR]

PurposeWe present a randomized study of tubeless or nephrostomy-free percutaneous nephrolithotomy (PCNL), a modification of the standard technique, compared with standard PCNL to evaluate the role of tubeless PCNL in minimizing postoperative discomfort and reducing duration of hospital stay.Patients and methodsTwo hundred and two patients undergoing PCNL were randomized to two groups Group A (standard PCNL) with nephrostomy tube placement postoperatively, and group B (tubeless PCNL) with antegrade placement of a Double-J stent without nephrostomy. Inclusion criteria were normal renal functions, single tract procedure with complete clearance, and minimal bleeding at completion. The two groups were comparable in age and sex and in metabolic and anatomic features. Factors evaluated included postoperative pain, analgesia requirement, blood loss, postoperative morbidity, hospital stay, and time to recovery.ResultsAll patients had an uneventful postoperative recovery. The average visual analogue scale pain score on postoperative day 1 for group A patients was 59 5.1 compared with 31 4.8 in group B (P< 0.01). The mean analgesia requirement for group A (meperidine 126.5 33.3 mg) was significantly more compared with group B (meperidine 81.7 24.5 mg) (P< 0.01). The difference in average blood loss and urinary infection for the two groups was not statistically significant. The incidence of urinary leakage from the nephrostomy site was significantly less for the tubeless group (0101), compared with the standard PNL group (7101). The average hospital stay in the tubeless group (21.8 3.9 hours) was significantly shorter than that of the standard PCNL group (54.2 5 hours) (P< 0.01). Tubeless group patients took 5 to 7 days for complete convalescence whereas standard PCNL patients recovered in 8 to 10 days. No long-term sequelae were noticed in the median follow-up period of 18 months in any patient.ConclusionNephrostomy-free or tubeless PCNL reduces postoperative urinary leakage and local pain related to the drainage tube. It also minimizes hospital stay; the majority of patients were discharged from the hospital in fewer than 24 hours. [ABSTRACT FROM AUTHOR]

Purpose To characterize the flow of a novel ureteral stent composed of a nickel-cobalt-chromium-molybde-num alloy and compare it with flow in a standard ureteral stent.Materials and Methods Six 6F Resonance stents and six 6F standard Black Beauty ureteral stents were placed in six Yucatan minipigs, with each pig serving as its own control. Flow assessment was performed on all stents via a nephrostomy tube delivering a standard rate of 0.9 saline at 35 cm H2O. Flow studies on the standard stents encompassed extraluminal (i.e., lumen of stent occluded with a guidewire), intraluminal (i.e., ureter secured to stent with a constricting suture), and combined (i.e., open lumen without constricting suture) flow. In the Resonance stent, only combined and intraluminal flow could be addressed, as there is no access to the lumen of this stent.Results With the Resonance stent, intraluminal flow was much greater than combined flow, with mean values of 5.15 mLmin and 2.50 mLmin, respectively (P 0.057; SD 7.73). Intraluminal flow was similar to combined flow in the 6F standard stent, with mean values of 7.34 mLmin and 7.30 mLmin, respectively (P 0.88; SD 1.76). The standard stent had significantly greater combined flow than the Resonance stent (P 0.023) but not intraluminal flow (P 0.247). Of note, whereas it was possible to occlude the 6F standard stent completely with a ureteral ligature (i.e., no guidewire placed in the lumen), it was not possible to occlude the Resonance stent regardless of how tightly the suture was tied.Conclusion The Resonance metal alloy stent provides less overall flow than a standard stent. However, under circumstances of extrinsic ureteral compression sufficient to occlude a standard stent (e.g., extrinsic compression plus an internal guidewire), the metal stent continues to provide satisfactory drainage. [ABSTRACT FROM AUTHOR]

Background The Hopkins rod-lens nephroscope has been the standard in percutaneous renal surgery. Despite its high resolution, it is bulky when an external camera and light source are attached. Therefore, new technology to make the scopes lighter and more ergonomic is needed.New Technology The new Invisio Smith digital nephroscope is the first digital nephroscope from Gyrus ACMI. It was used for the first time in two patients with caliceal stones. The tip houses dual LED-driven light carriers and a 1-mm digital camera, which obviate the need for an external light source and camera, thus eliminating the risk of drape fires and patient burns. The Smith nephroscope is much lighter (470 g vs. 939 g) and more ergonomic when compared to the standard rod-lens nephroscope.Conclusions The Smith digital nephroscope is much lighter, more ergonomic and safer. Long term use is needed to test its durability. [ABSTRACT FROM AUTHOR]

The author reflects on an article related to ureteroscopy-directed retrograde nephrostomy technique by Jason B. Wynberg and colleagues appeared in a previous issue of the journal. He mentions that in this technique, preoperative imaging is used for selecting the calix. He informs that ureteroscopic and fluoroscopic guidance are used for the safety of the nephrostomy tract.