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Purpose: Secondary prevention has an important role in urinary stone disease. The core of secondary prevention is the identification of modifiable risk factors by a 24-hour urine collection, which then directs selective medical therapy. While this decreases the recurrence rate, little is known about the frequency with which 24-hour urine collections are obtained. Materials and Methods: Using medical claims from 2002 to 2006 we identified adults with incident urinary stone episodes. With appropriate diagnosis codes we determined those at high risk for recurrence. Of these patients we determined the proportion in whom a 24-hour urine collection was done within 6 months of diagnosis. Finally, we fitted regression models to measure associations between patient and provider level factors, and obtaining a 24-hour urine collection. Results: We identified 28,836 patients at high risk for recurrence. The prevalence of 24-hour urine testing increased from 7.0% in 2003 to 7.9% in 2006 (p = 0.011), although the overall prevalence was exceedingly low at 7.4%. Multivariable regression revealed that region of residence and level of comorbid illness were independently associated with 24-hour urine collection, as was the type of physician who performed the followup. For instance, the odds of metabolic evaluation were 2.9 times higher when a patient was seen by a nephrologist (OR 2.92, 95% CI 2.32–3.67), and more than threefold higher when seen by a urologist (OR 3.87, 95% CI 3.48–4.30). Conclusions: Obtaining 24-hour urine collections in stone formers at high risk is uncommon, raising a quality of care concern. [ABSTRACT FROM AUTHOR]

Purpose: We assess the accuracy of a biopsy directed treatment algorithm in correctly assigning active surveillance vs treatment in patients with small renal masses by comparing biopsy results with final surgical pathology. Materials and Methods: From 1999 to 2011, 151 patients with small renal masses 4 cm or smaller underwent biopsy and subsequent surgical excision. Biopsy revealed cell type and grade in 133 patients, allowing the hypothetical assignment of surveillance vs treatment using an algorithm incorporating small renal mass size and histological risk group. We compared the biopsy directed management recommendation with the ideal management as defined by final surgical pathology. Results: Biopsy called for surveillance of 36 small renal masses and treatment of 97 small renal masses. Final pathology showed 11 patients initially assigned to surveillance should have been assigned to treatment (8.3% of all patients, 31% of those recommended for surveillance), whereas no patients moved from treatment to surveillance. Agreement between biopsy and final pathology was 92%. Using management based on final pathology as the reference standard, biopsy had a negative predictive value of 0.69 and positive predictive value 1.0 for determining management. Of the 11 misclassified cases, 7 had a biopsy indicating grade 1 clear cell renal cancer which was upgraded to grade 2 (5) or grade 3 (2). After modifying the histological risk group assignment to account for undergrading of clear cell renal cancer, agreement improved to 97%, with a negative predictive value of 0.86 and a positive predictive value of 1.0. Conclusions: Our results suggest that compared to final pathology, biopsy of small renal masses accurately informs an algorithm incorporating size and histological risk group that directs the management of small renal masses. [Copyright &y& Elsevier]

Purpose: We compared the characteristics and outcomes of patients treated with percutaneous nephrolithotomy in the CROES (Clinical Research Office of the Endourological Society) Global Study according to preoperative renal function. Materials and Methods: Prospective data on consecutive patients treated with percutaneous nephrolithotomy in a 1-year period were collected from 96 participating centers. The glomerular filtration rate was estimated using the Modification of Diet in Renal Disease formula based on preoperative serum creatinine measurement. Patients were divided into 3 groups by glomerular filtration rate, including chronic kidney disease stages 0/I/II—greater than 60, stage III—30 to 59 and stages IV/V—less than 30 ml/minute/1.73 m2. Patient characteristics, operative characteristics, outcomes and morbidity were assessed. Results: Estimated glomerular filtration rate data were available on 5,644 patients, including 4,436 with chronic kidney disease stages 0/I/II, 994 with stage III and 214 with stages IV/V. A clinically significant minority of patients with nephrolithiasis presented with severe chronic kidney disease. A greater number of patients with stages IV/V previously underwent percutaneous nephrolithotomy, ureteroscopy or nephrostomy and had positive urine cultures than less severely affected patients, consistent with the higher incidence of staghorn stones in these patients. Patients with chronic kidney disease stages IV/V had statistically significantly worse postoperative outcomes than those in the other chronic kidney disease groups. Conclusions: Poor renal function negatively impacts the post-percutaneous nephrolithotomy outcome. By more aggressive removal of kidney stones, particularly staghorn stones, at first presentation and more vigilantly attempting to prevent recurrence through infection control, pharmacological or other interventions, the progression of chronic kidney disease due to nephrolithiasis may be mitigated. [Copyright &y& Elsevier]

Purpose: Minimally invasive nephron sparing surgery is gaining popularity for small renal masses. Few groups have evaluated robot-assisted partial nephrectomy compared to other approaches using comparable patient populations. We present a matched pair analysis of a heterogeneous group of surgeons who performed robot-assisted partial nephrectomy and a single experienced laparoscopic surgeon who performed conventional laparoscopic partial nephrectomy. Perioperative outcomes and complications were compared. Materials and Methods: All 249 conventional laparoscopic and robot-assisted partial nephrectomy cases from January 2007 to June 2010 were reviewed from our prospectively maintained institutional database. Groups were matched 1:1 (108 matched pairs) by R.E.N.A.L. (radius, exophytic/endophytic properties, nearness of tumor to collecting system or sinus, anterior/posterior, location relative to polar lines) nephrometry score, transperitoneal vs retroperitoneal approach, patient age and hilar nature of the tumor. Statistical analysis was done to compare operative outcomes and complications. Results: Matched analysis revealed that nephrometry score, age, gender, tumor side and American Society of Anesthesia physical status classification were similar. Operative time favored conventional laparoscopic partial nephrectomy. During the study period robot-assisted partial nephrectomy showed significant improvements in estimated blood loss and warm ischemia time compared to those of the experienced conventional laparoscopic group. Postoperative complication rates, and complication distributions by Clavien classification and type were similar for conventional laparoscopic and robot-assisted partial nephrectomy (41.7% and 35.0%, respectively). Conclusions: Robot-assisted partial nephrectomy has a noticeable but rapid learning curve. After it is overcome the robotic procedure results in perioperative outcomes similar to those achieved with conventional laparoscopic partial nephrectomy done by an experienced surgeon. Robot-assisted partial nephrectomy likely improves surgeon and patient accessibility to minimally invasive nephron sparing surgery. [Copyright &y& Elsevier]

Purpose: Prior studies suggest poor long-term incorporation of laparoscopy into urology practice after a postgraduate course. We evaluated the influence of the American Urological Association Mentored Laparoscopy Course on urologist clinical practice. Materials and Methods: The 2-day Mentored Laparoscopy Course includes lectures, standardized dry laboratory training with videotape analysis and a porcine laboratory with consistent mentors. Surveys to assess the impact of the course were sent in April 2010 to the 153 urologists who had taken the course from 2004 through 2009. Results: Of the 153 surveys 91 (60%) were returned a mean of 34.5 months after completing the course. Of the respondents 82% were in a group private practice, followed by solo private practice (15%) and full-time academic practice (3%). Of the respondents 92% reported that they had sutured laparoscopically, 52% had sutured a bleeding vessel and 51% had performed reconstructive laparoscopy since taking the course. Of the respondents 77% reported that their laparoscopic practice had expanded since taking the course (mean 2.9 cases monthly). Of the 41 respondents (45%) who now performed robotic surgery (mean 3.8 cases monthly) 39 (95%) thought that the course experience had helped with the transition into robotic surgery. Overall survey respondents were pleased with the experience during the course with 89 of 91 (98%) stating that they would recommend the course to a colleague. Conclusions: Long-term results reveal that the American Urological Association Mentored Laparoscopy Course attendees reported expansion in their laparoscopic practice since taking the course. They described the course as benefiting the transition to robotic surgery. [ABSTRACT FROM AUTHOR]

Purpose: Since to our knowledge the population level impact of laparoscopy on post-radical nephrectomy morbidity and mortality remains unknown, we compared the rates of postoperative complications and failure to rescue (the fatality rate in patients with a complication) in patients treated with laparoscopic vs open radical nephrectomy. Materials and Methods: Using linked SEER (Surveillance, Epidemiology and End Results)-Medicare data we identified patients with kidney cancer who were treated with laparoscopic or open radical nephrectomy from 2000 through 2005. After measuring the frequency of postoperative complications and failure to rescue we fit multivariate logistic regression models to estimate the association of these outcomes with surgical approach, adjusting for patient characteristics, cancer severity and surgery year. We also assessed the relationship between case volume, complications and failure to rescue. Results: We identified 2,108 (26%) and 5,895 patients (74%) treated with laparoscopic and open radical nephrectomy, respectively. The overall rates of complications and failure to rescue were 36.9% and 5.3%, respectively. The predicted probability of any, major, medical and surgical complications was 15%, 12%, 13% and 23% lower, respectively, after laparoscopic than after open radical nephrectomy (each p <0.05). Despite less frequent complications patients treated with laparoscopic radical nephrectomy had a greater probability of failure to rescue (7.6% vs 4.6%, p = 0.010). Higher volume surgeons and hospitals had a lower rate of failure to rescue in patients treated with radical nephrectomy (each p <0.05) but not with open radical nephrectomy. Conclusions: Supporting the decreased morbidity of laparoscopy, patients treated with radical nephrectomy had fewer complications than those who underwent open radical nephrectomy. However, failure to rescue was more common in patients with a complication after radical nephrectomy, suggesting that these events may be more difficult to recognize and manage successfully, especially among less experienced surgeons and hospitals. [Copyright &y& Elsevier]

Purpose: Risk factors for conversion to hand assisted laparoscopic or open surgery during laparoscopic renal surgery are incompletely defined. Materials and Methods: We reviewed our institutional database of 759 standard laparoscopic and 833 hand assisted laparoscopic radical, simple, donor and partial nephrectomies, pyeloplasties and nephroureterectomies from June 1996 to February 2009, representing a total of 1,592 cases. We identified the incidence of and indications for conversion to hand assisted laparoscopic and open surgery, and determined risk factors for conversion. Results: Of all 1,592 procedures 20 (1.3%) required conversion to open surgery. Of 759 standard laparoscopic procedures 21 (2.8%) were converted to hand assisted laparoscopic surgery and 1.7% were converted to open surgery for an overall standard laparoscopy conversion rate of 4.6%. Only 0.7% of hand assisted laparoscopic procedures were converted to open surgery. The rate of conversion to open surgery ranged from 0.3% for laparoscopic partial to 2.5% for laparoscopic simple nephrectomy. The rate of conversion to hand assisted laparoscopic surgery ranged from 0% for laparoscopic pyeloplasty to 6.5% for laparoscopic partial nephrectomy. Conversion to open surgery was most likely due to hemorrhage (50% of cases) or failure to progress (40%) while conversion to hand assisted laparoscopic surgery was most likely due to failure to progress (76%) and tumor anatomy (19%). Multivariate analysis revealed that the only significant risk factor for conversion to open surgery was greater American Society of Anesthesiologists score. Conversion to hand assisted laparoscopic surgery was associated with greater body mass index, American Society of Anesthesiologists score and partial nephrectomy. Conclusions: Conversion during laparoscopic renal surgery to open or hand assisted laparoscopic surgery is a rare but important event in laparoscopic surgery. The risk is influenced by the nature of the procedure and overall patient health. [Copyright &y& Elsevier]

Purpose: We evaluated the long-term safety, efficacy and durability of ureteroscopic laser papillotomy for chronic flank pain associated with renal papillary calcifications. Materials and Methods: We reviewed the medical records of all patients who underwent ureteroscopic laser papillotomy in the absence of free urinary calculi at our institutions from 1998 through 2008. Success was defined as patient report of significant pain relief. The duration of response was considered the time from papillotomy to repeat papillotomy in the same renal unit, patient report of recurrent pain or final followup. Results: Ureteroscopic Ho:YAG laser papillotomy was done a total of 176 times in 65 patients, including 147 unilateral and 29 bilateral procedures. Of the patients 39 underwent multiple procedures (2 to 12). Symptomatic followup was available in 50 patients (146 procedures) during a mean of 38 months. Significantly less pain was reported after 121 procedures (83%). The mean duration of response per procedure was 26 months and 30 patients (60%) had a mean remission duration of greater than 1 year. Postoperatively hospital admission was required after 14 procedures (8%). There was no significant change in the mean estimated glomerular filtration rate during a mean 41.3-month followup. Seven of the 65 patients (11%) had hypertension before papillotomy. In 3 of the 49 patients (6.1%) with adequate followup new hypertension developed during a mean of 38 months. Conclusions: Ureteroscopic laser papillotomy is safe and effective. In patients with papillary calcifications and characteristic chronic, noncolicky pain this procedure provides significant, moderately durable symptom relief. [ABSTRACT FROM AUTHOR]

Purpose: We compared outcomes in patients treated with nephroureterectomy vs nephron sparing endoscopic surgery for upper tract urothelial carcinoma. Materials and Methods: Patients treated at our institution for upper tract urothelial carcinoma from 1996 to 2004 were monitored for upper tract and bladder recurrence, metastasis, and cancer specific and overall survival. Outcomes were compared between treatment groups by univariate and multivariate analyses based on pertinent pathological and demographic variables. Results: Of 96 renal units 62 underwent immediate nephroureterectomy and 34 were managed endoscopically. Median followup in all survivors was 77 months. Overall nephroureterectomy and endoscopy complication rates were 29% and 9.3%, respectively. In patients with low grade tumors the 5-year metastasis-free survival rate after nephroureterectomy and endoscopy was 88% and 94%. The corresponding 5-year cancer specific and overall survival rates were 89% vs 100% and 72% vs 75%, respectively. Of endoscopic cases 84% had at least 1 ipsilateral recurrence. Multivariate analysis revealed that only tumor grade was significantly associated with metastasis-free survival while grade and body mass index correlated with cancer specific survival, and Charlson Comorbidity index and grade impacted overall survival. Treatment group was not associated with survival outcome. Conclusions: When technically feasible and in select patients, endoscopic management provides cancer related and overall survival equivalent to that of nephroureterectomy in patients with low grade upper tract urothelial carcinoma at the cost of frequent re-treatments in many patients. Nephroureterectomy is standard treatment for high grade cancer when there is a normal contralateral kidney but endoscopy should be considered when there are imperative indications for nephron sparing. [Copyright &y& Elsevier]

Purpose: We assessed the influence of renal ischemia on long-term global renal function after laparoscopic partial nephrectomy in patients with 2 functioning kidneys in a large, multicenter cohort. Materials and Methods: Collected data included demographic, clinical and surgical characteristics, tumor parameters and renal function outcomes at 4 institutions in a total of 401 patients with 2 functioning kidneys who underwent laparoscopic partial nephrectomy. Renal function was assessed in the immediate postoperative period (days 1 to 3) and at last followup (greater than 1 month) using the estimated glomerular filtration rate calculated by the 4-variable Modification of Diet in Renal Disease equation. Ischemia time and covariates were modeled on the percent change in the estimated glomerular filtration rate using linear regression. Results: Median ischemia time was 29 minutes (IQR 22, 34). The postoperative change and the last (long-term) change in the estimated glomerular filtration rate were −16% and −11%, respectively. Median time to the last estimated glomerular filtration rate measurement was 13 months (IQR 6, 24). On multivariate analysis shorter ischemia and operative times, external or ureteral irrigation with cold saline and female gender were associated with less postoperative percent change in the estimated glomerular filtration rate. Smaller tumor size and absent diabetes were associated with less of a final percent change in the estimated glomerular filtration rate. Ischemia time was not associated with a percent change in the estimated glomerular filtration rate at last followup. Conclusions: Within the range of times in these series renal ischemia did not have a clinically significant impact on global renal function in patients with 2 functioning kidneys who underwent laparoscopic partial nephrectomy, as measured by the estimated glomerular filtration rate. [Copyright &y& Elsevier]

Purpose: We assessed the impact of approach (standard vs hand assisted) and specimen handling (morcellation vs intact extraction) on laparoscopic radical nephrectomy short-term recovery and long-term oncological outcome. Materials and Methods: Of 255 patients with pathologically confirmed and presumed localized renal cell carcinoma 147 underwent standard and 108 underwent hand assisted laparoscopic radical nephrectomy. Specimen handling was done by intact extraction in 132 cases and morcellation in 123. Perioperative data were recorded prospectively and oncological surveillance was reviewed retrospectively. Results: Despite significant differences in body mass index, mass size, T stage and pathological risk between the groups there were no statistically significant differences in perioperative outcome by approach or specimen handling except greater estimated blood loss (mean 406 vs 283 ml), longer hospital stay (mean 2.8 vs 2.4 days) and greater time to recovery (mean 13 vs 9.9 days) in the hand assisted vs the standard group. Discovery of pT3 disease was not significantly different between the specimen handling groups after controlling for mass size. Multivariate analysis of 5-year Kaplan-Meier survival curves revealed that neither approach nor specimen handling impacted recurrence-free, cancer specific or overall survival. Conclusions: Differences in perioperative outcomes attributable to the specific approach (standard vs hand assisted) and the method of specimen handling (morcellation vs intact extraction) at laparoscopic radical nephrectomy have minimal clinical significance. There are no discernible differences in long-term oncological efficacy. The choice of approach and specimen handling for laparoscopic radical nephrectomy can be based on surgeon and patient preference, cosmetic considerations and other factors. [Copyright &y& Elsevier]

Purpose: We noted that the impact of obesity on renal laparoscopy may vary with the specific surgical approach. Materials and Methods: Patients who underwent standard and hand assisted laparoscopic radical nephrectomy at our institution were categorized by body mass index as nonobese—body mass index less than 30, obese—30 to 39.9 and morbidly obese—40 kg/m2 or greater. We assessed the association of intraoperative and postoperative outcomes with body mass index for standard and hand assisted laparoscopic radical nephrectomy. Results: Of 350 patients who underwent standard (196) or hand assisted (154) laparoscopic radical nephrectomy 36% were obese and 12% were morbidly obese. Patients who underwent hand assisted laparoscopic radical nephrectomy had a greater body mass index, more frequent assignment of American Society of Anesthesiologists score 3 or 4 and larger masses than those who underwent standard laparoscopic radical nephrectomy. Despite this fact conversion to open surgery from hand assisted laparoscopic radical nephrectomy did not occur, while such conversion occurred in the standard laparoscopic radical nephrectomy group in 0.8% of nonobese, 3.0% of obese and 17% of morbidly obese patients (association with body mass index p = 0.003). Operative time, intraoperative and postoperative complications, and hospitalization duration did not vary with body mass index. On multivariate analysis only body mass index and not age, gender, American Society of Anesthesiologists score, prior abdominal surgery or tumor size was associated with an increasing likelihood of conversion to open surgery (p = 0.04), and only in the standard laparoscopic radical nephrectomy group. Conclusions: Although obesity and morbid obesity are associated with more frequent conversion to open surgery during standard laparoscopic radical nephrectomy, such conversion did not occur during hand assisted laparoscopic radical nephrectomy. This advantage of hand assisted laparoscopic radical nephrectomy should be considered when planning laparoscopic radical nephrectomy in obese and morbidly obese patients. [Copyright &y& Elsevier]

Purpose: The diffusion of laparoscopic renal surgery has been gradual. While surgery for benign and malignant kidney disease is usually within the urological domain, donor nephrectomy is multidisciplinary. Therefore, we compared the use of laparoscopy by procedure indication (kidney donor, and benign and malignant kidney disease) to examine potential specialty specific associations with the slow uptake of this technology. Materials and Methods: Data on 53,461 patients undergoing nephrectomy for all indications between 1998 and 2003 were abstracted from the Nationwide Inpatient Sample using International Classification of Diseases, 9th Revision, Clinical Modification procedure and diagnostic codes. Generalized estimating equations were fitted to measure the association between laparoscopy use and the procedure indication (kidney donor, benign kidney disease and kidney cancer). Results: The use of laparoscopy varied by treatment indication. In 2003, 33% of kidney donors underwent a laparoscopic approach compared to 22% and 16% of patients with benign and malignant kidney disease, respectively (p <0.0001). After adjusting for patient and hospital differences patients with benign (adjusted OR 0.71, 95% CI 0.58–0.94) and malignant (adjusted OR 0.51, 95% CI 0.35–0.74) kidney disease were significantly less likely to undergo laparoscopic nephrectomy than kidney donors. Conclusions: These data highlight that the use of laparoscopic renal surgery varies by procedure indication with slower adoption of laparoscopy for malignant or benign indications than for donor nephrectomy. This variation was not readily explained by differences in measurable patient and hospital factors. Further characterization of provider and nonclinical characteristics may provide additional insight into differences in the adoption of this technology, which appears to be a specialty specific phenomenon. [Copyright &y& Elsevier]

Purpose: Focused ultrasound therapy is a promising modality for noninvasive tissue ablation. However, the relative contributions of thermal and cavitational effects are poorly defined. We characterized the ultrasound parameters within which tissue ablation occurs by cavitational mechanisms without significant thermal effect. Materials and Methods: In vitro porcine kidneys were submerged in degassed water. Tissue ablation was performed by delivering ultrasound (750 kHz and 20 microsecond pulses) of constant spatial peak energy dose (100 J/cm2) to adjacent foci in a 3 × 3 grid configuration. For each ablation different intensity (0.11 to 211 kW/cm2) and duty cycle (0.04% to 100%) parameters were selected. A thermocouple co-localized with the center of each grid continuously measured temperature. Following ablation each kidney was examined grossly and histologically. Results: Ablated tissue lesions were classified into 4 discrete morphological categories, including blanched—firm, pale, desiccated tissue, disrupted—a cavity containing thin, isochromatic liquid, mixed—a cavity containing pale, thick liquid with minimal blanching and no grossly visible effect. Morphologically similar lesions clustered at separable regions of the ultrasound parameter space. The maximal temperature attained in disrupted lesions was similar to that attained when there was no effect (44.2C and 47.2C, respectively, p = 0.31), although it was significantly lower than the maximal temperatures for desiccated or mixed lesions (67.5C and 59.4C, each p <0.0001). Conclusions: In an in vitro model we defined the ultrasound parameter region within which purely cavitational ablation of tissue is possible with a negligible thermal component. Additional research is needed to optimize the parameters for in vivo cavitational tissue ablation, incorporating the influence of tissue perfusion. [Copyright &y& Elsevier]

Purpose: Surgical paradigms may change in the era of laparoscopic surgery. We evaluated a conservative nonsurgical approach to postoperative hemorrhage following laparoscopic upper retroperitoneal surgery as opposed to the more traditional strategy of reexploring the surgical site. Materials and Methods: In 911 laparoscopic procedures performed in 8 years we retrospectively identified risk factors and characterized treatment for postoperative hemorrhage. Results: We considered postoperative hemorrhage to be present when postoperative transfusion was required that could not be accounted for by operative blood loss or another definable cause outside of the surgical field. Red blood cell transfusion was required after 53 procedures (5.8%), of which 34 (3.7%) were done for postoperative hemorrhage. Postoperative hemorrhage occurred only after nephrectomy in 3.3% of cases, after partial nephrectomy in 9.9% and after adrenalectomy in 5.4%. Multivariate analysis revealed a significant association of postoperative hemorrhage with patient age and American Society of Anesthesiologists score (preoperative factors), operative time and splenic injury (intraoperative factors), and gastrointestinal complications and prolonged hospitalization (postoperative factors). Postoperative hemorrhage increased mean hospitalization from 2.5 to 6.4 days. No significant differences in post-hospital recovery were associated with postoperative hemorrhage. Only 4 of the 34 patients (12%) required surgical management of postoperative hemorrhage. All other cases were conservatively managed. Outcome after surgical and conservative management did not differ except postoperative renal complications tended to be more common in the former cases (50% vs 7%). Conclusions: Most patients with hemorrhage following laparoscopic upper retroperitoneal surgery can be treated with conservative nonsurgical interventions. [Copyright &y& Elsevier]

Purpose: There may be inherent costs associated with the cultivation of laparoscopic expertise. We compared the cost trends for laparoscopy during the development of our program with that of open surgery for renal neoplasms. Materials and Methods: We retrospectively reviewed the records of 381 patients treated surgically for renal cortical neoplasms from 1998 to 2003. Demographic information and cancer specific data were recorded on each subject. Direct variable costs, which are directly traceable to the patient care service provided and vary with patient volume, were used to analyze cost. Temporal trends were assessed using multivariate models developed to determine smoothed mean costs by year. Results: Although it was initially more expensive, by 2003 mean costs were lower for laparoscopic than for open radical nephrectomy ($5,157 vs $5,808). This reflected a significantly lower annual increase in direct variable costs for laparoscopy vs open surgery even after adjustment for patient age, sex, race and clinical stage (p = 0.013). Although a similar trend was observed when comparing nephron sparing procedures vs open surgery, this did not attain statistical significance. In addition to surgical technique, only higher clinical stage was independently associated with increased direct variable costs after adjustment for operative year (p <0.0001). Conclusions: Relative to their open counterparts the costs of laparoscopic treatment of renal cortical neoplasms have increased at a lower rate in the last 6 years. When considered in the context of the well established benefits of laparoscopy, our findings lend additional support in favor of laparoscopy as the standard of care. [Copyright &y& Elsevier]

Purpose: Despite the popularity of hand assisted laparoscopic donor nephrectomy published experience is less than that with standard laparoscopic donor nephrectomy and few critical assessments of operative maneuvers have been described. Materials and Methods: We describe the impact of changes in operative technique made by a single surgeon during 200 hand assisted laparoscopic donor nephrectomies. Results: With a mean operative time of 229 minutes and hospital stay of 1.9 days the rates of conversion to open surgery, intraoperative complications and major postoperative complications were 1%, 1.5% and 6%, respectively. Lasting changes in technique were dissection of a ureteral/gonadal packet, bipolar cautery use on gonadal/adrenal/lumbar veins and resting the kidney before removal. The incidence of ureteral complications decreased from 8% to 5.1% with dissection of the ureter in conjunction with the gonadal vein rather than isolating it. Warm ischemia time decreased from a mean of 186 to 143 seconds with bipolar electrocautery instead of clips to control gonadal/adrenal/lumbar veins. After starting to rest the kidney before removal the incidence of primary graft nonfunction and delayed function decreased from 6.7% to 0% and 30% to 11.8%, respectively, with a corresponding improvement in 2-year graft survival from 83% to 95%. Conclusions: This large series of hand assisted donor laparoscopic nephrectomies with a mean followup approaching 3 years demonstrates that the procedure is safe for the donor and procures a good specimen. Decreases in ureteral complications, warm ischemia time and graft dysfunction might be attributable to specific changes in our operative technique. [Copyright &y& Elsevier]

Purpose: The optimal minimally invasive treatment for small renal masses continues to evolve. Current ablative technologies rely on thermal mechanisms for tissue destruction. However, the creation of precise lesions is limited by inhomogeneous heating/cooling due to tissue variability, perfusion effects and tissue charring. We hypothesized that nonthermal mechanical effects of ultrasound (cavitation) can be used to progressively homogenize tissue in controlled fashion with predictable results. Materials and Methods: We developed a focused annular array ultrasound system capable of delivering high intensity (greater than 20 kW/cm) short pulses (20 microseconds) of energy to a target volume. This system operates at a repetition frequency of 100 Hz, resulting in a low time averaged power output (approximately 5 W total acoustic output). Following approval from the institutional animal care committee a series of transcutaneous ablations were performed in the normal kidneys of 10 rabbits. Results: Lesions created with a small number of pulses (10 or 100) produced scattered areas of damage characterized by focal hemorrhage and small areas of cellular injury in the targeted volume. Lesions created with greater numbers of pulses (1,000 or 10,000) demonstrated complete destruction of the targeted volume. Gross examination revealed that lesions contained a liquefied core with smooth walls and sharply demarcated boundaries. Histological examination demonstrated extensive areas of acellular debris surrounded by a narrow margin of cellular injury. Conclusions: This pulsed cavitational ultrasound system is capable of transcutaneous nonthermal destruction of renal tissue. Refinement of this technology for noninvasive ablation of small renal masses is currently under way. [Copyright &y& Elsevier]

Abstract: Purpose: The optimal management of lower pole renal calculi is controversial. We compared shock wave lithotripsy (SWL) and ureteroscopy (URS) for the treatment of patients with small lower pole stones in a prospective, randomized, multicenter trial. Materials and Methods: A total of 78 patients with 1 cm or less isolated lower pole stones were randomized to SWL or URS. The primary outcome measure was stone-free rate on noncontrast computerized tomography at 3 months. Secondary outcome parameters were length of stay, complication rates, need for secondary procedures and patient derived quality of life measures. Results: A total of 67 patients randomized to SWL (32) or URS (35) completed treatment. The 2 groups were comparable with respect to age, sex, body mass index, side treated and stone surface area. Operative time was significantly shorter for SWL than URS (66 vs 90 minutes). At 3 months of followup 26 and 32 patients who underwent SWL and URS had radiographic followup that demonstrated a stone-free rate of 35% and 50%, respectively (p not significant). Intraoperative complications occurred in 1 SWL case (unable to target stone) and in 7 URS cases (failed access in 5 and perforation in 2), while postoperative complications occurred in 7 SWL and 7 URS cases. Patient derived quality of life measures favored SWL. Conclusions: This study failed to demonstrate a statistically significant difference in stone-free rates between SWL and URS for the treatment of small lower pole renal calculi. However, SWL was associated with greater patient acceptance and shorter convalescence. [Copyright &y& Elsevier]