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Purpose: Though controversial, alpha blockers are used widely for ureteral stone passage. However, its effects on the patient-reported Quality of life (QOL) is unknown. We compared the QoL of patients on alpha-blocker medical expulsive therapy (MET) to patients not on MET (noMET) utilizing the validated Wisconsin Stone Quality of Life (WISQOL)., Methods: This prospective study included patients prescribed either MET or noMET after presentation with symptomatic, obstructing ureteral stones. The treatment arm was decided at the point of care by the initial treating physician and included analgesia and antiemetics. Tamsulosin (0.4 mg daily) was prescribed for the MET group. The WISQOL survey was administered at baseline, 7-, 14-, 21- and 28-days following discharge from the ED or until stone expulsion., Results: 197 patients were enrolled, of which 116 (59.2%) completed questionnaires for analysis, 91 in the MET group and 25 in noMET. Average ureteral stone size was 4.7 mm (SD 1.8) and 3.1 mm (SD 1.0) for MET and noMET, respectively. Of completed surveys, 105 (90%) were completed at day 7, 67 (57.6%) at day 14, 53 (45.7%) at day 21, and 40 (34.5%) at day 28. MET was associated with improved QoL scores across all WISQOL domains compared to noMET. Stone size, age, race, sex, comorbidity score and a prior stone history were not associated with reduced QoL., Conclusions: The use of MET was associated with improved QOL on all WISQOL metrics compared to noMET patients. Improved stone QOL may be an indication of alpha-blocker therapy in patients with ureteral stone colic., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Introduction: Nephron-sparing surgery is important in patients with multiple renal tumors, especially if associated with a solitary kidney or hereditary syndrome. Prior studies have shown partial nephrectomy (PN) of multiple ipsilateral renal masses to have good oncologic and renal function outcomes. We aim to compare renal function changes, complications, and warm ischemia time (WIT) of partial nephrectomy of a single renal mass (sPN) vs those of partial nephrectomy of multiple ipsilateral renal masses (mPN). Materials and Methods: We retrospectively reviewed our multi-institutional PN database. We matched robotic sPN and mPN patients ∼3:1 using "nearest neighbor" propensity score matching based on age, Charlson comorbidity index (CCI), total tumor size, and nephrometry score. Univariate analysis was performed, and multivariable models were fit controlling for age, gender, CCI, and tumor size. Results: Fifty mPN and 146 sPN patients were matched. The mean total tumor size was 3.3 and 3.2 cm, respectively ( p  = 0.363). The mean nephrometry score in both groups was 7.3 and 7.2, respectively ( p  = 0.772). Estimated blood loss (EBL) was 137.6 and 117.8 mL, respectively ( p  = 0.184). The mPN group had higher operative time (174.6 vs 156.4 minutes, p  = 0.008) and WIT (17.0 vs 15.3 minutes, p  = 0.032). There was no significant difference in the change in glomerular filtration rate (mPN -6.4% vs sPN -8.7%, p  = 0.712). Complications (Clavien 2+) occurred in 10.2% of mPN and 11.3% of sPN patients ( p  = 0.837). A multivariable linear model predicts a nonstatistically significant difference of 1.4 minutes of additional WIT in the mPN group ( p  = 0.242). There was no statistical difference in complication rates between groups in a multivariable model (odds ratio 1.00, p  = 0.991). Conclusions: Robotic PN in our multi-institutional matched comparison of mPN and sPN showed no difference in complications, renal functional outcomes, or EBL. mPN was associated with increased operative time and WIT, though the WIT difference was not significant on multivariable analysis.

Introduction: Vacuum-assisted ureteral access sheaths (V-UASs) are a new tool designed to evacuate dust or small fragments during retrograde intrarenal surgery (RIRS). There are reports of increased stone-free rates, decreased infections, and decreased operative time with V-UAS usage. The optimal technique and setting for V-UAS has yet to be described. Herein, we investigate real-time intrarenal pressure (IRP) throughout a range of settings using V-UAS in a porcine RIRS model. Materials and Methods: Ureteroscopy was performed in three female porcine cadaver kidneys through a ClearPetra V-UAS. IRP was recorded through a percutaneous catheter at different inflow pressures, sheath sizes, sheath distance from the ureteropelvic junction, and suction settings. Magnitude of change in delta IRP (dIRP) was compared at various settings. Results: There was no statistical difference in IRP when comparing no suction with vent inactivated. As expected, IRP decreased with larger sheath size and lower irrigation pressures. Average IRP dropped ∼18 mm Hg with suction activation (42.30 mm Hg, vent inactivated; 24.45 mm Hg IRP, suction activated; p  < 0.0001). Irrigation pressure and sheath size did not make a difference in the dIRP. dIRP was significantly greater at lower suction settings compared with max suction (25.44 dIRP at 200 mm Hg suction, 10.26 mm Hg dIRP at max suction, p  = 0.04). In a subset of observations, IRP paradoxically increased to higher than IRP with no suction at all after >5 seconds of activated suction. Conclusion: Use of V-UAS during RIRS can lower mean IRP; however, this effect could reverse with extended suctioning especially under conditions of high vacuum (>200 mm Hg) owing to outflow tract collapse. Our results suggest urologists should use lower suction settings and short, <5-second bursts to maximize therapeutic benefit, and minimize potential shortcomings of V-UAS during RIRS.

Introduction: Management of malignant ureteral obstruction (MUO) with ureteral stents remains a clinical challenge, often involving frequent stent exchanges attributable to stent failure or other urological complications. We report our institutional experience with ureteral stents for management of MUO, including analysis of clinical factors associated with stent failure. Methods: We performed a retrospective review of patients treated with indwelling ureteral stents for MUO in nonurothelial malignancies at our tertiary-care institution between 2008 and 2019. Univariate Cox proportional hazards analysis was performed to identify clinical variables associated with stent failure and stent-related complications. Stent failure was defined as need for unplanned stent exchange, placement of percutaneous nephrostomy (PCN), or tandem stents. Results: In our cohort of 78 patients, the median (range) number of stent exchanges was 2 (0-17) during a total stent dwell time of 4.3 (0.1-40.3) months. Thirty-four patients (43.6%) developed a culture-proven urinary tract infection (UTI) during stent dwell time. Thirty-five patients (44.8%) had stent failure. Twenty-two patients (28.2%) underwent unplanned stent exchanges, 23 (29.5%) required PCN after initial stent placement, and 6 (7.7%) required tandem stents. Ten (28.6%) patients with stent failure were treated with upsized stents, which led to resolution in seven patients. Stent failure occurred with 20/44 (45.4%) Percuflex™, 15/27 (55.6%) polyurethane, and 2/3 (66.7%) metal stents. In patients with ≥2 exchanges ( N  = 45), median time between exchanges was 4.1 (2.0-14.8) months. Bilateral stenting and history of radiation predicted UTI development. Median overall patient survival after initial stent placement was 19.9 months (95% CI 16.5-37.9 months). Conclusions: Ureteral stent failure poses a significant medical burden to patients with MUO. Better methods to minimize stent-related issues and improve patient quality of life are needed. Using a shared decision-making approach, clinicians and patients should consider PCN or tandem stents early in the management of MUO.

To determine whether androgen, estrogen, and/or progesterone signaling play a role in the pathophysiology of adherent perinephric fat (APF). We prospectively recruited patients undergoing robotic assisted partial nephrectomy during 2015-2017. The operating surgeon documented the presence or absence of APF. For those with clear cell renal cell carcinoma (ccRCC), representative sections of tumor and perinephric fat were immunohistochemically stained with monoclonal antibody to estrogen α, progesterone, and androgen receptors. Patient characteristics, operative data, and hormone receptor presence were compared between those with and without APF. Of 51 patients total, 18 (35.3%) and 33 (64.7%) patients did and did not have APF, respectively. APF was associated with history of diabetes mellitus (61.1% vs 24.2%, p = 0.009) and larger tumors (4.0 cm vs 3.0 cm, p = 0.017) but not with age, gender, BMI, Charleston comorbidity index, smoking, or preoperative estimated glomerular filtration rate. APF was not significantly associated with length of operation, positive margins, or 30-day postoperative complications but incurred higher estimated blood loss (236.5 mL vs 209.2 mL, p = 0.049). Thirty-two had ccRCC and completed hormone receptor staining. The majority of tumors and perinephric fat were negative for estrogen and progesterone while positive for androgen receptor expression. There was no difference in hormone receptor expression in either tumor or perinephric fat when classified by presence or absence of APF (p > 0.05). APF is more commonly present in patients with diabetes or larger tumors but was not associated with differential sex hormone receptor expression in ccRCC., (© 2021. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

Introduction: Herein we evaluate the incidence of incisional lumbodorsal hernia (ILDH) after retroperitoneal robotic partial nephrectomy (RRPN) and associated patient-specific and tumor-specific risk factors. Furthermore, we aim to evaluate the role of routine lumbodorsal fascial closure for the prevention of ILDH. Methodology: This is a retrospective review of our robotic partial nephrectomy database of all RRPNs performed at Washington University School of Medicine from 2000 to 2020. Postoperative imaging was reviewed for evidence of ILDH. A clinically significant hernia was defined as the protrusion of visceral organ(s) through the lumbodorsal fascia. Patient and tumor characteristics, and fascial closure techniques were analyzed to determine predictors of ILDH. Results: In total, 150 patients underwent RRPN between 2007 and 2020 with an average follow-up of 4.9 (1-37) months. Twelve (8%) ILDHs were identified. Ten (6.7%) patients had herniated retroperitoneal fat whereas 2 (1.3%) patients had herniated colon. All were asymptomatic and managed conservatively. On matched cohort comparison, patients with ILDH had larger tumors than patients without an incisional hernia (3.9 cm vs 2.8 cm, p  = 0.029). In general, patient factors were no different between patients with and without ILDH. However, coronary artery disease (CAD) was more prevalent in patients with ILDH (33.3% vs 10.9%, p  = 0.028). Patients with ILDH were more likely to have a port site extended for specimen extraction (66.7% vs 38.2%, p  = 0.069). Lumbodorsal fascial closure and type of suture material were not associated with prevention of ILDH ( p  = 0.545, p  = 0.637). Conclusion: The radiographic incidence of lumbar incisional hernias after RRPN without routine fascial closure of the extraction incision was 8%. All were asymptomatic and did not require surgical repair. Larger tumor size and CAD were associated with ILDH.

Introduction: The proportion of robotic procedures continues to rise. The literature reinforces that robotic procedures take longer and are often more costly. We compared cost and perioperative outcomes of laparoscopic radical nephrectomy (LRN) and robot-assisted radical nephrectomy (RARN) at our high-volume center. Materials and Methods: We retrospectively reviewed our 2012-2015 data repository for patients undergoing RARN and LRN for a renal mass. Perioperative and oncologic outcomes were compared. We performed a multivariate analysis of operative time, estimated blood loss, length of stay (LOS), and overall and major 90-day complication rates while controlling for demographic data, Charlson comorbidity index (CCI), tumor size, and surgeon factors. We compared fixed, variable, and distinct procedural costs. Results: We identified 99 LRN and 95 RARN cases. There was no difference in demographic data, tumor size, preoperative renal function, and malignant histology. LRN patients had more comorbidities (49.5% vs 27.3% CCI 2+, p  = 0.018). The mean preoperative glomerular filtration rate was higher in the robotic cohort (84.8 vs 75.1, p  = 0.48). Mean operative time was 32.7 minutes longer ( p  = 0.002) and estimated blood loss 145 mL higher ( p  = 0.007) for the RARN cohort. There was no difference in mean LOS. Major and all 90-day complication rates were no different. The mean procedural cost for RARN was higher by $464 when controlling for operative time ( p  < 0.001). Fixed costs were not statistically different. Variable costs for RARN were estimated to be $2,310 higher ( p  = 0.045). Conclusions: Even with cost-conscious, experienced renal surgeons, RARN is associated with a longer procedure, higher supply costs, and higher hospitalization costs. There was no difference in positive surgical margin and complications. There were fewer 30-day readmissions for the RARN cohort, which may represent under-recognized cost savings. With fewer LRN cases in the United States each year, discussion to address cost is warranted. Without better outcomes for robotic surgery, a change in reimbursement to cover costs is unlikely to happen.

Introduction and Objective: African American (AA) race has been identified to have a higher incidence of chronic kidney disease (CKD) and worse renal cancer survival compared with Caucasian Americans (CA), irrespective of tumor size, pathologic type, and surgical procedure. We aimed to compare the outcomes between CA and AA patients undergoing minimally invasive partial nephrectomy (PN) at our high-volume center. Materials and Methods: We queried our PN data repository from 2007 to 2017. We identified 981 cases of PN (robotic n  = 943 and laparoscopic n  = 38), of which there were 852 CA and 129 AA patients. We compared age, sex, body mass index (BMI), operative time, estimated blood loss (EBL), nephrometry score, tumor size, pre- and postoperative estimated glomerular filtration rate (eGFR), length of stay, Charlson Comorbidity Index (CCI), tumor characteristics, and 30-day complication rate. We then estimated the overall survival and disease-specific survival. Results: Age, BMI, operative time, EBL, nephrometry score, tumor size, CCI, length of stay, and sex were not statistically different. The mean preoperative eGFR was higher in the AA cohort (91.4 mL/min/1.73 m 2 vs 86.1 mL/min/1.73 m 2 , p  = 0.007); however, at 1 year, there was no mean difference (76.8 mL/min/1.73 m 2 vs 74.5 mL/min/1.73 m 2 , p  = 0.428). There was a higher percentage of Fuhrman Grade 3/4 in the AA cohort (33.3% vs 22.5%, p  = 0.044). The AA cohort had a 2.66 × higher incidence of papillary renal cell carcinoma (RCC) (34.9% vs 13.1%, p  < 0.001) and unclassified RCC (3.9% vs 0.4%, p  = 0.001). There was no difference in tumor stage ( p  = 0.260) or incidence of benign histology (15.3% vs 11.6%, p  = 0.278). There were no differences in 30-day complications ( p  = 0.330). The median follow-up was 43.2 months. By using Kaplan-Meier curves, there was no observed difference in overall survival ( p  = 0.752) or disease-free survival ( p  = 0.403). Conclusions: Our cohort of AA and CA patients with intermediate follow-up showed no worse outcomes for CKD or survival when undergoing laparoscopic or robotic PN. For low-stage renal cancer, there was no difference in overall survival and disease-free survival at a median follow-up of 43.2 months among AA patients, despite having higher grade tumors and a higher percentage of unclassified RCC. Our cohort of AA patients did have a higher incidence of papillary RCC. The equivalent overall survival and disease-free survival could be due to the earlier discovery of lower stage renal masses incidentally identified on imaging studies performed equally for other reasons in both AA and CA patients.

Objective: It has been previously reported that warming irrigation fluid higher than body temperature may decrease ureteral spasm and thereby facilitate ureteroscopic access to the proximal ureter. Our objective was to examine the effects on ureteral peristalsis and ureteral diameter if the irrigant was warmed to just under the biological threshold for injury. Materials and Methods: Two female adult Yorkshire pigs were studied in this pilot study. In the first pig, a dilute mixture of contrast and irrigation fluid at 37°C and then at 43°C was instilled for 30 minutes into each renal pelvis through a ureteral catheter at 40 mm Hg. Retrograde pyelogram images were captured for each trial and the caliber of the ureter was measured using Vitrea ® software. In the second pig, a lumbotomy was performed, and a magnetic sensor was placed on the extraluminal surface of the ureter to monitor ureteral peristalsis while repeating the aforedescribed regimen. Thirty minutes after the first regimen, the force exerted during placement of a 16F ureteral access sheath (UAS) was recorded at both temperatures using the University of California, Irvine Ureteral Force Sensor. Results: There was no statistically significant difference in ureteral caliber along the length of the ureter at 43°C ( p  = 0.87, p  = 0.32, p  = 0.66 for proximal, middle, and distal ureter, respectively). Indeed, there was an increase in peristalsis from baseline with fluid irrigation at 37°C and at 43°C (59% and 65%, respectively). There was no significant difference in the force exerted for UAS placement at either temperature. On histologic analysis, there were no significant changes in ureteral histology or luminal diameter. Conclusions: In a porcine model, warming irrigation fluid to just under the biological threshold for injury did not increase ureteral caliber, decrease ureteral peristalsis, or facilitate UAS placement. As such, during ureteroscopy, we continue to warm our irrigation fluid just to body temperature.

Introduction: For patients with clinically localized renal masses, positive surgical margins (PSMs) after robotic partial nephrectomy (RPN) have been associated with a higher risk of disease recurrence, although some studies have challenged this conclusion. Owing to inconsistent reports and a lack of long-term robotic data, the clinical impact of PSM after RPN remains uncertain. We evaluate long-term (>6 years) survival outcomes after RPN in patients with clinically localized disease with respect to surgical margin status. Methods: We conducted a retrospective review of patients who underwent RPN for clinically localized renal masses from June 2007 to December 2012 at Washington University School of Medicine. Disease recurrence and overall survival (OS) were stratified on the presence or absence of PSM. The cohort was analyzed to identify patient- and tumor-specific characteristics associated with PSM. Results: We identified 374 RPNs performed from 2007 to 2012 with a mean follow-up time of 77.7 months (SD 32.2 months). PSM was identified in 12 (3.2%) patients. Patients with PSM were at 14-fold increased risk for recurrence with no difference in OS ( p  < 0.001, p  = 0.130, respectively). Patients with PSM had higher incidence of chronic obstructive pulmonary disease (COPD) (25% vs 6.4%) and greater blood loss (425 mL vs 203 mL). Conclusion: With an extended follow-up period of 77 months after RPN, we found that PSM substantially increased the risk of recurrence without impacting OS. Our finding that PSM may occur more frequently in older patients with COPD must be confirmed in larger studies.

Introduction: With increased demands on surgeon productivity and outcomes, residency robotics training increasingly relies on simulations. The objective of this study is to assess the validity and effectiveness of an ex vivo porcine training model as a useful tool to improve surgical skill and confidence with robot-assisted partial nephrectomy (RAPN) among urology residents. Methods: A 2.5 cm circular area of ex vivo porcine kidneys was marked as the area of the tumor. Tumor excision and renorrhaphy was performed by trainees using a da Vinci Si robot. All residents ranging from postgraduate year (PGY) 2 to 5 participated in four training sessions during the 2017 to 2018 academic year. Each session was videorecorded and scored using the global evaluative assessment of robotic skills (GEARS) by faculty members. Results: Twelve residents completed the program. Initial mean GEARS score was 16.7 and improved by +1.4 with each subsequent session ( p  = 0.008). Initial mean excision, renorrhaphy, and total times were 8.2, 13.9, and 22.1 minutes, which improved by 1.6, 2.0, and 3.6 minutes, respectively (all p  < 0.001). Residents' confidence at performing RAPN and robotic surgery increased after completing the courses ( p  = 0.012 and p  < 0.001, respectively). Overall, residents rated that this program has greatly contributed to their skill (4/5) and confidence (4.1/5) in robotic surgery. Conclusions: An ex vivo porcine simulation model for RAPN and robotic surgery provides measurable improvement in GEARS score and reduction in procedural time, although significant differences for all PGY levels need to be confirmed with larger study participation. Adoption of this simulation in a urology residency curriculum may improve residents' skill and confidence in robotic surgery.

Introduction: Supracostal access for percutaneous nephrolithotomy (PNL) has a known increased risk for thoracic complications (TCs). In this study, we perform a radiological review of preoperative and postoperative abdominal CT scans to assess the relationship of the upper pole of the kidney with surrounding landmarks to determine radiographic predictors of TCs. Methods: We performed a retrospective matched cohort comparison of patients who underwent supracostal PNL with and without TCs from 2012 to 2019. An experienced genitourinary (GU) radiologist reviewed pre- and postoperative CT scans to measure the craniocaudal distance between the upper renal pole and the most superior calix to the upper edge of the tip of the 12th rib, the costophrenic angle, and the posterior insertion of the diaphragm. Results: We identified 19 patients who developed TCs after undergoing PNL and compared their CT scans with 24 control patients without TCs. On a preoperative abdominal CT scan, the relationship of the upper edge of the renal parenchyma or upper pole calix with the superior edge of the tip of the 12th rib or costophrenic angle was not found to be predictive of TCs. On receiver operating characteristic analysis, diaphragmatic insertion of ≤2.5 cm below the upper edge of the renal parenchyma on sagittal and transverse views was predictive of TCs ( p  = 0.046). On postoperative CT scan, the percutaneous nephrostomy tract traversed the posterior insertion of the diaphragm in 80% of patients who had TCs compared with 20% of patients who had no TCs. Conclusions: The decreased distance between the posterior insertion of the diaphragm (medial and lateral arcuate ligaments) and the superior edge of the renal upper pole on preoperative CT scan was associated with TCs from supracostal puncture during PNL. Critical preoperative recognition of this anatomic relationship can help preoperative planning and patient counseling and may prevent or reduce TCs.

Introduction: Nephrolithiasis is common after malabsorptive bariatric surgery; however, the comparative risk of stone formation after different bariatric surgeries remains unclear. We seek to compare the risk of stone diagnosis and stone procedure after gastric banding (GB), sleeve gastrectomy (SG), short-limb Roux-en-Y (SLRY), long-limb Roux-en-Y (LLRY), and biliopancreatic diversion with duodenal switch (BPDDS). Patients and Methods: Using an administrative database, we retrospectively identified 116,304 patients in the United States, who received bariatric surgery between 2007 and 2014, did not have a known kidney stone diagnosis before surgery, and were enrolled in the database for at least 1 year before and after their bariatric surgery. We used diagnosis and procedural codes to identify comorbidities and events of interest. Our primary analysis was performed with extended Cox proportional hazards models using time to stone diagnosis and time to stone procedure as outcomes. Results: The adjusted hazard ratio of new stone diagnosis from 1 to 36 months, compared to GB, was 4.54 for BPDDS (95% confidence interval [CI] 3.66-5.62), 2.12 for LLRY (95% CI 1.74-2.58), 2.15 for SLRY (95% CI 2.02-2.29), and 1.35 for SG (95% CI 1.25-1.46). Similar results were observed for risk of stone diagnosis from 36 to 60 months, and for risk of stone removal procedure. Male sex was associated with an overall 1.63-fold increased risk of new stone diagnosis (95% CI 1.55-1.72). Conclusions: BPDDS was associated with a greater risk of stone diagnosis and stone procedures than SLRY and LLRY, which were associated with a greater risk than restrictive procedures. Nephrolithiasis is more common after more malabsorptive bariatric surgeries, with a much greater risk observed after BPDDS and for male patients.

Introduction: Percutaneous cryoablation (PCA) has emerged as an alternative to extirpative management of small renal masses (SRMs) in select patients, with a reduced risk of perioperative complications. Although disease recurrence is thought to occur in the early postoperative period, limited data on long-term oncologic outcomes have been published. We reviewed our 10-year experience with PCA for SRMs and assessed predictors of disease progression. Materials and Methods: We reviewed our prospectively maintained database of patients who underwent renal PCA from March 2005 to December 2015 ( n  = 308). Baseline patient and tumor variables were recorded, and postoperative cross-sectional imaging was examined for evidence of disease recurrence. Disease progression was defined as the presence of local recurrence or new lymphadenopathy/metastasis. Results: Mean patient age was 67.2 ± 11 years, mean tumor size was 2.7 ± 1.3 cm, and mean nephrometry score was 6.8 ± 1.7. At mean follow-up of 38 months, local recurrence and new lymphadenopathy/metastasis occurred in 10.1% (31/308) and 6.2% (19/308) of patients, respectively. Excluding patients with a solitary kidney and/or von Hippel-Lindau, local recurrence and new lymphadenopathy/metastasis occurred in 8.6% (23/268) and 1.9% (5/268) of cases, respectively. Kaplan-Meier estimated disease-free survival was 92.5% at 1 year, 89.3% at 2 years, and 86.7% at 3 years post-PCA. Increasing tumor size was a significant predictor of disease progression (hazard ratio 1.32 per 1-cm increase in size, p  = 0.001). Conclusions: PCA is a viable treatment option for patients with SRMs. Increasing tumor size is a significant predictor of disease progression following PCA.

The aim of the present study was to compare the survival outcomes for patients with metastatic renal cell carcinoma (mRCC) who underwent laparoscopic cytoreductive nephrectomy (CN) vs. open CN vs. targeted therapy (TT) alone at our institution. A retrospective chart review was performed at our institution for patients who underwent CN prior to TT (laparoscopic, n=48; open, n=48) or who were deemed unfit for surgery and received TT alone (n=36), between January 2007 and December 2012. Kaplan-Meier estimated survival and Cox proportional hazards analyses were performed. Laparoscopic CN was associated with significantly longer survival compared with open CN or TT alone (median survival 24 vs. <12 months, respectively; P<0.01). On multivariate analysis, laparoscopic CN was an independent predictor of survival [hazard ratio (HR)=0.48, P<0.01), controlling for preoperative risk factors, while survival was similar between open CN and TT alone (HR=0.85, P=0.54). In our experience, laparoscopic CN appears to be a significant predictor of survival in mRCC. Selection bias of the surgeon for patients with improved survival may account for clinical variables that were otherwise difficult to quantify. For patients who were not candidates for laparoscopic CN, open CN did not confer a survival benefit over TT alone, while it was associated with increased morbidity., (Copyright © 2020, Spandidos Publications.)

Extracorporeal shock wave lithotripsy (SWL) is less invasive compared to the other invasive modalities of stone treatment that are gaining popularity. Hence, methods to improve the efficacy of SWL are desirable. We studied the effectiveness of dual frequency on the efficacy of stone fragmentation, but minimizing treatment time. A phantom 10 mm spherical BegoStone was fragmented in vitro in a kidney model using an electromagnetic lithotripter (Storz MODULITH ® SLX-F2). A total of 78 stones were fragmented each with 3000 shocks at 60 Hz or 120 Hz or a dual frequency (DF) of 60-120 Hz. For the DF setting, the first 1000 shocks were delivered at 60 Hz and the next 2000 at 120 Hz. Total weight and number of significant fragments of > 3 mm (TWSF and TNSF, respectively) and also > 2 mm was measured. Results: The mean TWSF was 0.1, 0.16, and 0.08 g for 60 Hz, 120 Hz, and DF 60-120 Hz, respectively. The TWSF of DF 60-120 Hz was significantly lower than that of 120 Hz (p = 0.02), but same as the 60 Hz (p = 0.32). The mean TNSF of > 3 mm was 2.6, 3.0, and 2.0 for 60 Hz, 120 Hz, and DF 60-120 Hz, respectively, without significant differences between each setting. However, increasing trend of TWSF, TW2 mm and TN2 mm was seen in the order of DF, 60 Hz and 120 Hz (p = 0.019, p = 0.004 and 0.017, respectively). Treatment time for 60 Hz, 120 Hz, and DF 60-120 Hz was 50, 25, and 34 min, respectively. Dual-frequency setting produced effective stone fragmentation compared to the recommended 60 Hz, while decreasing treatment time. DF variation is one other factor that may be tailored for effective stone comminution and needs clinical evaluation.

Background: In patients seen in the emergency department (ED) with acute stone obstruction many risk factors that indicate need for urgent renal drainage are known. However, in patients discharged from ED without renal drainage factors that can minimize revisit to the emergency department are not fully identified. We evaluated SIRS (systemic inflammatory response syndrome) as a risk factor for urgent renal drainage and revisit to the ED in patients with acute stone colic during their ED visit., Methods: Retrospective review was performed of patients presenting to a tertiary academic emergency department (ED) from an obstructing ureteral or UPJ stone with hydronephrosis confirmed on an abdominal and pelvic CT scan. Data evaluated over a 3-year period included stone size, presence of UTI, presence or absence of SIRS and other clinical variables as risk factors for urgent renal drainage and ED revisits., Results: 1983 patients with urolithiasis were seen at the ED and 649 patients had obstructive urolithiasis on CT scan. SIRS was diagnosed in 15% (99/649) patients. 54/99 (55%) patients with SIRS underwent urgent renal drainage compared to 99/550 (17%) in non-SIRS patients. In a multivariate analysis SIRS was a predictor of urgent intervention compared to non-SIRS patients (odds ratio 4.6, p < 0.05). SIRS was also associated with increased risk for revisits to the ED (6.9% with SIRS vs. 2.4% with no SIRS, odds ratio 2.9, p = 0.05)., Conclusions: Presence of SIRS in obstructive urolithiasis patients was an independent risk factor of acute urologic intervention and revisits to the ED. A timely consultation with a urologist following discharge from ED for obstructive stone patients with SIRS who had no acute renal drainage may prevent revisit to the ED. Evaluation for SIRS in addition to other clinical risk factors should be considered while making management decision in patients with acute stone obstruction.

We describe a rare case of a large renal arteriovenous malformation in a patient with von Willebrand disease. Initial attempts at technically challenging embolization failed requiring a nephrectomy. Extra-intestinal vascular malformations are rare in von Willebrand disease. However, there is more recent evidence of von Willebrand factor's regulatory role in angiogenesis and vascular malformations., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Defining cellular and molecular identities within the kidney is necessary to understand its organization and function in health and disease. Here we demonstrate a reproducible method with minimal artifacts for single-nucleus Droplet-based RNA sequencing (snDrop-Seq) that we use to resolve thirty distinct cell populations in human adult kidney. We define molecular transition states along more than ten nephron segments spanning two major kidney regions. We further delineate cell type-specific expression of genes associated with chronic kidney disease, diabetes and hypertension, providing insight into possible targeted therapies. This includes expression of a hypertension-associated mechano-sensory ion channel in mesangial cells, and identification of proximal tubule cell populations defined by pathogenic expression signatures. Our fully optimized, quality-controlled transcriptomic profiling pipeline constitutes a tool for the generation of healthy and diseased molecular atlases applicable to clinical samples.

Objective: To identify avoidable predictors of postureteroscopy (URS) unplanned encounters and to minimize 30-day encounters., Materials and Methods: We performed retrospective chart review and telephone surveys on patients who underwent URS for urolithiasis between January and June 2016. Univariate and multivariable analyses evaluated for potential predictors of unplanned encounters., Results: Of 157 patients, there were 44 (28.0%) unplanned patient-initiated clinical phone calls, 23 (14.6%) emergency department (ED) visits, and 8 (5.1%) readmissions, with pain being the most common complaint during the encounters. Factors associated with a higher rate of phone calls include first-time stone procedure (36.6% vs 20.9%, p = 0.029), outpatient status (30.3% vs 0%, p = 0.021), intraoperative stent placement (31.2% vs 0%, p = 0.006), and stent removal at home (58.8% vs 28.8%, p = 0.014). Factors associated with increased rate of ED visits were first-time stone procedure (22.5% vs 8.1%, p = 0.011) and ureteral access sheath (UAS) usage (29.6% vs 11.8%, p = 0.018). Factors associated with a higher rate of readmissions were lower body mass index (23.9 vs 29.7, p = 0.013), bilateral procedure (20.0% vs 2.9%, p = 0.010), and UAS usage (14.8% vs 3.1%, p = 0.032). Stone burden, operative time, Charlson comorbidity index, and preoperative urinary tract infection were not significantly associated with postoperative encounters., Conclusions: Pain, first-time stone treatment, presence of a ureteral stent, outpatient status, bilateral procedures, and UAS usage were common reasons for postoperative encounters after URS. Appropriate perioperative patient education and counseling and adequate pain management may minimize these encounters and improve treatment quality and patient satisfaction.

Bladder instrumentation engages the innate immune system via neutrophil activation, promoting inflammation and pain. Elevated levels of mitochondrial DNA (mtDNA) have been associated with tissue damage and organ dysfunction. We hypothesized that local bladder trauma induced by a Foley catheter (FC) will result in mtDNA release, migration of neutrophils into the bladder lumen, and activation of the Toll-like receptor 9 (TLR9) and nuclear factor kappa B (NF-κB) pathway leading to bladder tissue damage. We randomized 10 swine into two groups receiving uncoated, or chloroquine/N-Acetylcysteine (CQ/NAC)-coated FCs. Urine samples were analyzed for mtDNA activation of TLR9/NF-κB as demonstrated by indicators of neutrophil adhesion, migration, and activation. We found that uncoated FCs resulted in a unique active neutrophil phenotype that correlated with bladder epithelial injury, neutrophilia, necrosis, mtDNA release, TLR9/NF-κB activation, transcription and secretion of pro-inflammatory cytokines, and enhanced respiratory burst. In our study we observed that the high levels of mtDNA and elevated TLR9/NF-κB activity were ameliorated in the CQ/NAC-coated FC group. These findings suggest that post-migrated bladder luminal neutrophils are involved in local tissue damage and amelioration of the mtDNA/TLR9/NF-κB inflammatory axis may represent a therapeutic target to prevent inflammation, and bladder tissue injury.

Objective: To provide a training tool to address the technical challenges of robot-assisted laparoscopic partial nephrectomy, we created silicone renal tumor models using 3-dimensional printed molds of a patient's kidney with a mass. In this study, we assessed the face, content, and construct validity of these models., Materials and Methods: Surgeons of different training levels completed 4 simulations on silicone renal tumor models. Participants were surveyed on the usefulness and realism of the model as a training tool. Performance was measured using operation-specific metrics, self-reported operative demands (NASA Task Load Index [NASA TLX]), and blinded expert assessment (Global Evaluative Assessment of Robotic Surgeons [GEARS])., Results: Twenty-four participants included attending urologists, endourology fellows, urology residents, and medical students. Post-training surveys of expert participants yielded mean results of 79.2 on the realism of the model's overall feel and 90.2 on the model's overall usefulness for training. Renal artery clamp times and GEARS scores were significantly better in surgeons further in training (P ≤.005 and P ≤.025). Renal artery clamp times, preserved renal parenchyma, positive margins, NASA TLX, and GEARS scores were all found to improve across trials (P <.001, P = .025, P = .024, P ≤.020, and P ≤.006, respectively)., Conclusion: Face, content, and construct validity were demonstrated in the use of a silicone renal tumor model in a cohort of surgeons of different training levels. Expert participants deemed the model useful and realistic. Surgeons of higher training levels performed better than less experienced surgeons in various study metrics, and improvements within individuals were observed over sequential trials. Future studies should aim to assess model predictive validity, namely, the association between model performance improvements and improvements in live surgery., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Renal cell carcinoma accounts for 3-4% of adult malignant neoplasms and over 65,000 new cases of kidney cancer were diagnosed in the USA in 2013 [1, 2]. Widespread use of abdominal imaging is leading to an increased incidence in the detection of small renal masses (SRMs) among other causes [1-4]. In light of recent literature on the role of percutaneous renal mass biopsy and retrospective data analysis, surveillance for renal masses ≤4 cm is likely to become more common especially in patients with less aggressive pathology, advanced age and multiple medical comorbidities.

The ureter is possibly the least studied and most poorly understood organ of the urinary tract. The pathophysiologic basis underlying the use of α-blockers to improve ureteral stone passage or to treat ureteral stent symptoms is poorly understood. This, in part, may explain why clinical studies of medical expulsive therapy for ureteral stone passage are fraught with conflicting data. Methods to study human ureter in vivo are few and challenging. The findings of many of the ureteral studies are from observational in vitro studies and were evaluated in other animal species that may not be applicable in human beings. There are few mechanistic studies evaluating the underlying molecular pathophysiologic mechanisms of human ureter. This is critical to our understanding and treatment of stent symptoms, including the development of a patient friendly ureteral stent and for the pharmacologic modulation of ureteral activity. The following is an overview of some of the observational and mechanistic ureteral studies evaluating the pharmacologic and stent effects, including potential areas for further research.

Objectives: Treatment of a renal mass in patients with hematologic malignancy or on immunosuppression can be complex and is not well defined. Surgical excision or thermal ablation of renal mass is generally recommended in view of concern for tumor progression in immunosuppressed patients. We report our management decision experience in patients and literature review on concomitant renal and hematologic malignancy., Materials and Methods: A retrospective medical record review of patients with renal cell carcinoma (RCC) and a hematologic malignancy over 3 years at our University Hospital was performed. Data were collected including patient׳s demographics, renal tumor and hematologic malignancy characteristics (stage, pathologic subtype, time of diagnosis, treatment type and prognosis). Surgical and medical management of each malignancy was reviewed and perioperative and overall outcomes are reported., Results: In total, 6 patients were identified with RCC and a hematologic malignancy of which 4 were on immunosuppressive therapy. A total of 5 patients had leukemia and 1 patient had multiple myeloma. Most kidney tumors were stage I, 83%; and 80% were Fuhrman grade II. There was equal distribution of clear cell and papillary-type RCC. All but 1 patient had undergone nephron-sparing surgery. Overall, 50% of our patients died within 1 year after renal surgery for pT1a tumors from causes that are unrelated to renal cancer., Conclusions: Our small cohort showed significant mortality in patients with hematologic malignancy on immunosuppression, who had their renal mass treated with surgical excision or thermal ablation. However, this mortality was not secondary to surgical procedure itself. The prognosis of the hematologic malignancy might dictate the management of RCC., (Copyright © 2016 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)

Introduction: Clinical studies have shown beneficial role of oral alpha-blockers for ureteral stent-related morbidity. However, the in vivo effects of oral alpha-blockers on a stented ureter are unclear. We evaluated the effects of alpha-blockade on ureteral dynamics in a stented porcine ureter., Methods: Twenty-seven female pigs were used in this study. Fourteen pigs received oral alpha-blocker medication (silodosin, 8 mg daily), and 13 pigs received no medication. Under cystoscopic guidance, a 5F ureteral catheter was positioned in the renal pelvis and attached to a pressure monitor. A Foley catheter was placed in the bladder along with a bladder pressure transducer. A lumbotomy was performed, and the ureter was identified. A magnetic sensor was placed on the extraluminal surface of the ureter to monitor ureteral peristalsis. We measured renal pelvic and bladder pressures, urine output, and ureteral peristalsis every hour for 10 minutes for a total of 5 hours. The pigs were then euthanized., Results: The mean weight was 42.5 kg in the drug group and 45.9 kg in the nondrug group (p = 0.008). Mean hourly urine output was 140 mL in the drug group and 144 mL in the nondrug group (p = 0.76). Mean baseline renal pressure was 13.2 and 13.8 mm Hg (p = 0.69) in the drug and nondrug groups, respectively. Mean peristaltic renal pelvic pressure was 19.1 mm Hg in the drug group and 19.2 mm Hg in the nondrug group (p = 0.97). Mean number of peristalsis was 11/10 and 14/10 minutes (p = 0.03) in the drug and nondrug groups, respectively., Conclusions: Alpha-blockade in an in vivo stented porcine ureter resulted in no significant effect on renal pelvic pressure but a significant decrease in the number of ureteral peristalsis. Further investigation of the effects of alpha-blocker on ureteral dynamics is required to better understand its effects on stent-related symptoms.

Objective: To evaluate the role of stone size in predicting urinary calculus composition using Hounsfield units on noncontrasted computed tomography (CT) scan., Methods: A retrospective review was performed for all patients who underwent ureteroscopy or percutaneous nephrolithotomy during a 1-year period, had a stone analysis performed, and had CT imaging available for review. All CT scans were reviewed by a board-certified radiologist. Variables evaluated included age, sex, body mass index, stone size, stone location, Hounsfield units (HUs), and stone composition., Results: We identified a total of 91 patients (41 men and 50 women) with CT imaging and stone analysis available for review. Stone analysis showed 41 calcium oxalate monohydrate (CaOxMH), 13 calcium oxalate dihydrate, 29 calcium phosphate, 5 uric acid, 2 struvite, and 1 cystine stone. Average age was 46 years, and average body mass index was 32 kg/m2. Measured HUs varied significantly with size for CaOxMH and calcium oxalate dihydrate stones (P values <.05), but not for calcium phosphate stones (P = .126). Using a CaOxMH identification value of 700-1000 HUs, 28 of 41 stone compositions (68%) would not have been correctly identified, including all 10 (100%) small (<5 mm) stones, 13 of 22 (59%) medium (5-10 mm) stones, and 5 of 9 large (>10 mm) stones (55%)., Conclusion: For calcium stones, the ability of CT HUs to predict stone composition was limited, likely due to the mixed stone composition. Within a cohort of CaOxMH stone formers, measured HUs varied linearly with stone size. All stones <5 mm were below thresholds for CaOxMH composition., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Purpose: Encrusted ureteral stents are a challenging endourologic problem. We performed a multi-institutional review of percutaneous nephrolithotomy (PCNL) as primary treatment for encrusted stents., Materials and Methods: We identified 36 patients who underwent PCNL for treatment of an encrusted stent. A retrospective review was performed to compile details of procedures and outcomes for these patients., Results: In 36 patients, 38 renal units underwent PCNL for encrusted ureteral stents. The mean patient age was 47.1 years (±16.7), and the female:male ratio was 15:21. Mean stent indwelling time before removal was 28.2 months (±27.8). The reason for long indwelling time was reported in 25 cases; these reasons included "patient unaware stent needed to be removed" (17 cases), pregnancy (2 cases), other comorbidities (3 cases), and patient incarceration (3 cases). In 3 cases, the stent had become encrusted within 3 months of placement. Mean operative time was 162 minutes (±71). There were no major intraoperative complications, and no patients required blood transfusion. Litholapaxy was required for bladder coil encrustations in 22 cases (58%), and ureteroscopy with lithotripsy was required for encrustation of the ureteral portion of the stent in 13 cases (34.2%). Second look percutaneous procedures were required in 13 cases (34.2%). The stent was removed at the time of PCNL without need for concomitant or delayed ureteroscopy and/or cystolitholapaxy in 8 cases (21%). Ultimately, all stents were removed successfully. Patients were rendered stone free according to radiographs in 24 cases (63%)., Conclusions: In this multicenter review, PCNL is confirmed to be a safe and effective means of addressing the retained and encrusted ureteral stent. PCNL without ureteroscopy or litholapaxy was sufficient in a minority of cases (21%). Adjunctive endourologic modalities are often required, and the surgeon should anticipate the need for concomitant antegrade ureteroscopic laser lithotripsy and/or cystolitholapaxy. Although complete stent removal can be anticipated, residual fragments are not uncommon.

Background and Purpose: The discovery of thick, adherent, perinephric sticky fat (PSF) is relatively common during open or laparoscopic retroperitoneal surgery. To our knowledge, however, there has been no previous analysis of clinical or radiographic features associated with the development of PSF or of perioperative outcomes for those patients in whom it is found. Our objective is to analyze potential predictive features and determine whether there is any effect on clinical or pathologic outcomes for patients with perinephric sticky fat., Patients and Methods: Patients undergoing partial nephrectomy or laparoscopic cryoablation with available preoperative imaging were identified from 2005 to 2011. Operative records were reviewed to identify patients with and without PSF. Preoperative images and medical records were examined to obtain patient data regarding potential predictors as well as clinical and pathologic outcomes., Results: A total of 29 patients were identified-16 with PSF and 13 controls. Statistically significant factors associated with PSF included sex, tumor size, presence of perinephric stranding, tumor >50% exophytic, and thickness of perinephric fat (P<0.05). Median total operative time for patients with sticky fat was nearly 40 minutes longer than the control group (228 min vs 190 min, P<0.05). All four (17%) patients with Fuhrman grade 3 or 4 renal-cell carcinoma were from the sticky fat group (P=0.09)., Conclusions: Despite the small sample size, multiple possible factors associated with perinephric sticky fat were identified and may provide guidance for future investigation of this phenomenon.

Purpose: Multiple scoring systems have been proposed to standardize the description of anatomical features of renal tumors. However, it remains unclear which of these systems, if any, is most useful, or whether any performs better than simply reporting tumor size or location in patients undergoing partial nephrectomy. To clarify these issues we evaluated the association of tumor size, location, R.E.N.A.L. (Radius/Exophytic/Nearness to collecting system/Anterior/Location), PADUA (Preoperative Aspects and Dimensions Used for an Anatomical classification) and centrality index scores with perioperative outcomes., Materials and Methods: Patients undergoing partial nephrectomy with available preoperative imaging were identified from 2005 to 2011. R.E.N.A.L., PADUA and centrality index scores were assigned according to the described protocols for those systems. Associations between each variable and ischemia time, estimated blood loss, total operative time and change in estimated glomerular filtration rate were examined., Results: A total of 162 patients were identified with a median tumor size of 3.1 cm (IQR 2.2 to 4.6). Median estimated blood loss, ischemia time and total operative time were 200 ml (IQR 100 to 300), 24 minutes (IQR 20 to 30) and 211 minutes (IQR 179 to 249), respectively. Each scoring system was found to have a statistically significant (p <0.001) correlation with ischemia time, with the centrality index system showing the strongest correlation. Furthermore, each of the scoring systems showed a stronger correlation with ischemia time than tumor size or tumor location., Conclusions: Each scoring system outperformed tumor size and location, and may be useful when describing the surgical complexity of renal tumors treated with partial nephrectomy., (Copyright © 2012 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Purpose: The purpose of the study was to prospectively compare operative and postoperative characteristics and outcomes in elderly patients undergoing percutaneous nephrolithotomy (PCNL) compared with younger patients., Patients and Methods: Prospectively collected data from the Clinical Research Office of the Endourological Society (CROES) Global PCNL Study database were used. Elderly patients were defined as those aged 70 years and above, while younger patients were those between 18 and 70 years of age. Matched and unmatched group comparisons were performed based on imaging modality used for assessing stone-free status. Patient characteristics, operative data, and postoperative outcomes were compared., Results: The median age of the elderly group vs the young group was 74 years (range 70-93 years) vs 49 years. In the unmatched analysis, staghorn stones were seen at higher rates in the elderly group (27.8% vs 21.8%, P=0.014); however, the mean stone size was not significantly different (465.0 vs 422.8, P=0.063). The length of hospitalization was significantly longer in the elderly group compared with the young group in the unmatched analysis (5 days vs 4.1 days, P<0.001). The same difference was not apparent in the matched analysis (5.0 days vs 4.4 days, P=0.288). Overall complication rates were not significantly different in the unmatched analysis. In the matched analysis, however, a statistically significant higher rate of overall complications was seen. Stone-free rates were similar among all groups., Conclusion: PCNL in elderly patients over the age of 70 years produces results comparable to those seen in younger patients. With only a slightly higher-be it statistically significant-complication rate, the stone-free rate in older patients was the same as in the younger group.

Objectives: To evaluate the potential impact of the experience of the first assistant on the positive surgical margin rate (PSMR) after laparoscopic radical prostatectomy (LRP). The impact of training surgical residents and fellows on patient outcomes is difficult to quantify., Methods: A single-institution prospective database of 303 patients who underwent LRP between 2003 and 2008 was evaluated. The potential impact of the experience of the first assistant on the PSMR was evaluated by examining the relationship between the PSMR and the time of the academic year. Multivariable logistic regression analysis was used to adjust for patient age, Gleason's sum, tumor density, and pathologic stage., Results: Overall positive margin rate was 18.2%. Positive margin rate for July and August (14/45, 31.1%) was significantly higher than for the remaining 10 months (41/258, 15.9%) P = .015. The increased risk of positive margin in July/August remained significant after adjusting for age, Gleason's sum, tumor density, and pathologic stage (OR 2.65, 95% CI 1.21-5.79, P = .015), Conclusions: LRP performed with the first assistant in the first 2 months of the academic training year have a significantly higher PSMR., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Purpose: Alpha blockade has been well described clinically for expulsion of distal ureteral stone. However, the in-vivo effects of α-blockade on ureteral dynamics during stone passage are not clear. We studied the effects of oral alfuzosin on ureteral pressure and peristalsis in a distally obstructed porcine ureter., Methods: Twenty-four female domestic swine (75-82 kg) were incorporated into the study. The study was powered to detect a 30% difference in distal ureteral pressure, with a secondary endpoint of frequency of ureteral peristalsis. The animals were divided into four equal groups: a control group without α-blockade or ureteral obstruction, a group with α-blockade and no ureteral obstruction, a cohort without α-blockade but with distal ureteral obstruction, and a group with α-blockade and distal obstruction. Peristalsis was measured by a magnetic sensor and ureteral pressure through a 5F ureteral balloon catheter. Observations were recorded for 10-minute intervals every hour for 5 consecutive hours., Results: There was increase in ureteral pressure and peristaltic rate with distal ureteral obstruction (p < 0.01). Alpha blockade did not produce significant changes in the above parameters with or without ureteral obstruction compared with the nonmedicated groups. We observed a 0.2 mm Hg lower increase in change of ureteral pressure during peristalsis compared with resting ureteral pressure (delta pressure) in the treated obstructed model (95% confidence interval: -0.55 -0.10; p = 0.06)., Conclusions: In the porcine model, alfuzosin appears to decrease the delta pressure in the distal ureter during obstruction; however, statistical significance was not reached. Further investigation into the in-vivo physiology of medical expulsive therapy is warranted.

Introduction: Laparoscopic partial nephrectomy has emerged as a standard of care for small renal masses. Nevertheless, there remains concern over the potential for irreversible insult to the kidney as a result of exposure to warm ischemia. We aim to investigate the utility of selective segmental arterial clamping as a means to reduce the potential for ischemic damage to a solitary kidney during laparoscopic partial nephrectomy utilizing a porcine model., Materials and Methods: A total of 20 domestic swine were randomized into four equal groups. Each subject underwent laparoscopic radical nephrectomy to create the condition of a solitary kidney. On the contralateral side, a laparoscopic lower pole partial nephrectomy was performed, employing either selective or nonselective vascular clamping for either 60 or 90 minutes. Postoperatively, clinical status and serial serum studies were closely monitored for 1 week., Results: There were no intraoperative complications. The 90-minute nonselective clamping produced devastating effects, resulting in rapid deterioration into florid renal failure within 72 hours. The 60-minute nonselective clamping group experienced modest but significant rises in both blood urea nitrogen and creatinine. Both 60- and 90-minute selective clamping groups performed well, with no significant rises in creatinine over a 7-day period, and no instances of renal failure., Conclusions: Selective arterial clamping is a safe and feasible means of vascular control during laparoscopic partial nephrectomy. In the porcine model, selective clamping appears to improve functional outcomes during prolonged periods of warm ischemic insult. Prospective evaluation of the technique in humans is necessary to determine if selective arterial control confers long-term functional benefits in patients with limited renal reserve.

We demonstrate two techniques in this video clip that can be used when performing robotic-assisted laparoscopic partial nephrectomy. First, we use the fourth arm of the robot with a long-tip grasper to occlude the renal artery during the resection of the mass. Second, we show a novel method for securing the mattress sutures when performing the repair of the kidney. Both maneuvers help to increase the safety of the procedure and decrease the warm ischemia time to the kidney.

Cryoablation of renal masses is an evolving in situ ablative technique for the management of localized renal masses and can be performed in a laparoscopic or percutaneous manner. Its usefulness is increasing and correlates with the increasing frequency of incidentally diagnosed renal lesions. At present, this technique has been applied to patients deemed to be poor surgical candidates for extirpative therapy or those with a strong desire to avoid surgery, at least until long-term data become available to fully evaluate its cancer-control effectiveness. In addition, as costs become an ever more critical factor in healthcare, the costs of various management options for clinically localized kidney cancer will become as important as clinical outcomes in deciding appropriate treatment. We compare laparoscopic and percutaneous renal cryoablation from a cost perspective. Our findings indicate that percutaneous renal cryoablation may have distinct cost advantages over its laparoscopic counterpart. It remains to be seen whether these differences will translate into an overall increase in reliance on the percutaneous approach for renal cryoablation.

Background: Controversy exists about the impact of ischemia on renal function. We evaluated the creatinine clearance of patients having undergone laparoscopic renal extirpative and ablative surgery., Study Design: The records of patients undergoing laparoscopic procedures for renal masses from February 2000 to March 2004 were examined. Creatinine clearance (CrCl) for each patient was determined using the Cockcroft-Gault equation and ideal body weight. We compared CrCl changes of patients undergoing laparoscopic partial nephrectomy (without renal ischemia [LPN-none], with warm ischemia [LPN-warm], and with cold ischemia [LPN-cold]) with patients undergoing laparoscopic radical nephrectomy (LRN) and laparoscopic cryoablation. Patients predisposed to medical renal disease were substratified and evaluated., Results: All patients who underwent LRN or LPN-warm sustained a significant drop in CrCl on the first postoperative day, compared with patients who had LPN without ischemia or cryoablation (p < 0.01). The CrCl decrease correlated directly with warm ischemia time. Six months postoperatively, CrCl changes were no longer significant. Patients with medical renal disease risk factors were more likely to sustain longterm (1 year postoperatively) renal damage if they had renal ischemia, trending toward statistical significance., Conclusions: Ischemia causes acute renal damage, which is apparently reversible in patients without evidence of medical renal disease. Patients with known medical renal disease have substantial longterm changes in renal function associated with unilateral renal ischemia. Considering the insensitivity of creatinine-based renal function metrics, only eliminating ischemic time will realize the goal of maximal nephron preservation, particularly in patients with preexisting medical renal disease.

Purpose: To compare the efficiency and cost effectiveness of a combined pneumatic and ultrasonic lithotrite (Lithoclast Ultra) and a standard ultrasonic lithotrite, (LUS-1) during percutaneous nephrolithotomy., Materials and Methods: In a prospective randomized trial, 30 patients undergoing percutaneous nephrolithotomy (PCNL) were randomized to PCNL with either the combined pneumatic and ultrasonic lithotrite (PUL) or a standard ultrasonic lithotrite (SUL). Patient demographics, stone composition, location, pre- and post-operative stone burden, fragmentation rates, and device failures were compared., Results: There were 13 patients in the PUL group and 17 patients in the SUL group. Stone burden and location were equal. Overall, 64% of the PUL group had hard stones (defined as stones that were either pure or a mixture of cystine [3], calcium oxalate monohydrate [CaOxMono; 2], and calcium phosphate [CaPO4; 2]), and four had soft stones (3 struvite and 1 uric acid [UA]). In the SUL group, there were eight hard stones (5 CaOxMono and 3 CaPO4), and six soft stones (4 calcium oxalate dihydrate [CaOxDi] and 2 UA) (P = 0.51). Stone composition data were unavailable for five patients. Fragmentation time for the PAL was 37 minutes versus 31.5 minutes for the SUL (P = 0.22). Stone retrieval and mean operative times were similar for both groups. There were a total of three (23.1%) device-related problems in the PUL group, and eight (47%) in the SUL group. There was one (7.7%) device malfunction in the PUL group due to probe fracture. There were two (11.7%) device failures in the SUL group; one failure required the device to be reset every 30 minutes, and the second was an electrical failure. Suction tubing obstruction occurred twice (15.3%) in the PUL group and 35.3% in the SU group (P = 0.35). The stone-free rates for the PUL and SUL were 46% and 66.7%, respectively (P = 0.26)., Conclusion: Although the PUL was more costly, stone ablation and clearance rates were similar for both the combined pneumatic and ultrasonic device and the standard ultrasonic device. When stratified with respect to stone composition, the PUL was more efficient for harder stones, and the SUL was more efficient for softer stones.

Objectives: The majority of localized renal cancers are currently managed by laparoscopic radical nephrectomy, with or without the hand-assist device. In this prospective randomized study, we evaluated the patient outcomes with a standard laparoscopic radical nephrectomy (LRN) versus a hand-assisted laparoscopic radical nephrectomy (HALN)., Methods: Over a 3-year period, we randomly assigned 21 patients with a localized renal mass of 10 cm or larger to a LRN group with intact specimen extraction or a HALN. The trocar size and sites, the position of the hand-assist device, and the specimen extraction sites were standardized. Patient characteristics, surgical complications, postoperative pain, and convalescence were evaluated., Results: Twelve patients underwent LRN and 9 patients underwent HALN. Both groups had similar body mass indices (BMI), mean tumor diameter (LRN, 5.8 cm; HALN, 5.6 cm), and American Society of Anesthesiologists (ASA) scores. The HALN cohort was significantly older (mean age = 68 years) than the LRN cohort (mean age = 54 years) (P = 0.019). Perioperatively, both groups had similar mean times to oral intake and discharge (LRN 2.6 days and HALN 3 days, P = 0.6). Although both groups reported similar postoperative pain scale scores on day 1, at 1 and 3 months. Two patients in each group had complications (LRN 16% and HALN 22%)., Conclusions: In comparing HALN and LRN, there was no difference in the majority of operative and postoperative parameters, including hospital stay and postoperative pain. However, LRN patients had a significantly shorter convalescence with quicker return to normal activities and work than the HALN group. Part of the delay in long-term convalescence parameters may be due to the older patients in the HALN cohort.

In this manuscript some of the more common laparoscopic procedures and their indications will be reviewed.

Objectives: The long-term effects of shock wave lithotripsy on the growth of pediatric kidneys are not well defined. Likewise, no long-term data regarding renal growth after ureteroscopy or percutaneous nephrolithotomy have been published. We studied the effect of urolithiasis on renal growth in our pediatric patient population., Methods: A total of 165 children were treated for urolithiasis at St. Louis Children's Hospital from March 1993 to December 2003. Of these 165 children, 74 were available for long-term follow-up. Four groups were evaluated: those who underwent shock wave lithotripsy, ureteroscopy, or percutaneous nephrolithotomy, and those who received no intervention. The expected renal length was calculated using Chen's nomogram, and the observed renal length was measured using renal ultrasonography. All measurements were performed by one pediatric radiologist. The expected and observed renal growth was determined by subtracting the renal length at baseline from the length at follow-up, divided by the number of months of follow-up. Statistical analysis used paired data for each treatment group, and comparisons were made on a nonparametric single-rank method., Results: Of the 74 children, 39 were boys and 35 were girls, with a mean age at treatment of 9 years (range 9 months to 14 years) and a mean follow-up of 6.2 years (range 1.3 to 13.1). In all groups, the comparison between the treated side and nontreated side for expected and actual kidney size and growth was calculated as described. None of the groups had statistically significant differences in the observed or predicted renal growth rates., Conclusions: Shock wave lithotripsy, ureteroscopic stone extraction, and percutaneous nephrolithotomy do not appear to impair renal growth.

Background and Objectives: Traditional trocar tip design for laparoscopic access incorporates cutting blades to penetrate the body wall. More recently, trocars applying tissue dilation have been used that create a smaller defect, seldom requiring fascial wound closure. Four 12-mm commercially available single-use trocar designs were evaluated for postoperative pain., Methods: The 4-trocar types included 2 cutting (single or pyramidal bladed) and 2 dilating trocars (radially or axially dilating) type. Fifty-six patients undergoing transperitoneal laparoscopic renal surgery were randomized and blinded to one of the 4 trocar types. In each case, trocars were placed in a standard "diamond" configuration: three 12-mm study trocars and a lateral 5-mm trocar that served as a reference point for normalizing patients' pain scores. Postoperative pain based on a visual analog scale and complications were assessed., Results: No statistically significant difference existed in pain scores between different trocar types or trocar sites at 3-hour, 24-hour, and 1-week postoperative assessment time points. Eight (4.8%) minor complications occurred: bleeding in 7 (4.2%) and 1 (0.6%) wound infection. The radially dilating trocar had more device malfunction (P<0.05) than did the others., Conclusion: All 4 disposable trocars, muscle cutting or dilating type, were safe and yielded similar postoperative pain scores with or without the fascial wound closure after renal laparoscopy.