Phosphorus Content of Several Plant-Based Yogurts.

OBJECTIVE: In people with chronic kidney disease (CKD), hyperphosphatemia is a risk factor for mortality. Though unproven, dietary phosphorus control is considered essential in CKD. Although dietary and serum phosphorus are correlated, phosphorus from plant foods rich in phytate is less bioavailable than from animal and processed foods. Yogurt, valued for its low phosphorus and high protein, may be detrimental in CKD due to animal protein content. Plant-based yogurts (PBYs) might offer similar benefits without the downsides of animal protein, but little is known about their phosphorus content. DESIGN AND METHODS: Protein contents and phosphorus additives were gathered from nutrition labels of several PBYs, including almond, cashew, oat, coconut, and soy substrates. Phosphorus content was measured via emission spectrometry by Eurofins (Madison, WI), and the phosphorus-to-protein ratio (PPR) was calculated for each PBY. RESULTS: Phosphorus content was highest in Silk Soy Strawberry, Silk Almond Strawberry, and Siggi's Coconut Mixed Berries, while it was lowest in So Delicious Coconut Strawberry, Oatly Oat Strawberry, Forager Cashew Strawberry, and Kite Hill Almond Strawberry. Ingredient labels revealed that Silk Soy Strawberry, Silk Almond Strawberry, and Oatly Oat Strawberry contained phosphorus additives, and Siggi's Coconut Mixed Berries contained pea protein additives. Though from the same substrate class, So Delicious Coconut Strawberry and Siggi's Coconut Mixed Berries showed significant differences in phosphorus and protein contents. All seven PBYs had higher PPR ratios than dairy yogurts like Stonyfield Organic Oikos Strawberry, Chobani Nonfat Strawberry, and Yoplait Greek Strawberry. CONCLUSION: Low-PPR foods are important for CKD patients. Siggi's Coconut Mixed Berries had the lowest PPR, making it potentially the most desirable for CKD patients. However, there is high variability in PPR among PBYs with the same substrate; therefore, Delicious Coconut Strawberry had the highest PPR, highlighting the importance of product selection for patients with CKD.

Plant-Based Milk Alternatives and Risk Factors for Kidney Stones and Chronic Kidney Disease.

OBJECTIVE: Patients with kidney stones are counseled to eat a diet low in animal protein, sodium, and oxalate and rich in fruits and vegetables, with a modest amount of calcium, usually from dairy products. Restriction of sodium, potassium, and oxalate may also be recommended in patients with chronic kidney disease. Recently, plant-based diets have gained popularity owing to health, environmental, and animal welfare considerations. Our objective was to compare concentrations of ingredients important for kidney stones and chronic kidney disease in popular brands of milk alternatives. DESIGN AND METHODS: Sodium, calcium, and potassium contents were obtained from nutrition labels. The oxalate content was measured by ion chromatography coupled with mass spectrometry. RESULTS: The calcium content is highest in macadamia followed by soy, almond, rice, and dairy milk; it is lowest in cashew, hazelnut, and coconut milk. Almond milk has the highest oxalate concentration, followed by cashew, hazelnut, and soy. Coconut and flax milk have undetectable oxalate levels; coconut milk also has comparatively low sodium, calcium, and potassium, while flax milk has the most sodium. Overall, oat milk has the most similar parameters to dairy milk (moderate calcium, potassium and sodium with low oxalate). Rice, macadamia, and soy milk also have similar parameters to dairy milk. CONCLUSION: As consumption of plant-based dairy substitutes increases, it is important for healthcare providers and patients with renal conditions to be aware of their nutritional composition. Oat, macadamia, rice, and soy milk compare favorably in terms of kidney stone risk factors with dairy milk, whereas almond and cashew milk have more potential stone risk factors. Coconut milk may be a favorable dairy substitute for patients with chronic kidney disease based on low potassium, sodium, and oxalate. Further study is warranted to determine the effect of plant-based milk alternatives on urine chemistry.

Telemedicine Usage Among Urologists During the COVID-19 Pandemic: Cross-Sectional Study.

BACKGROUND: Prior to the COVID-19 pandemic, urology was one of the specialties with the lowest rates of telemedicine and videoconferencing use. Common barriers to the implementation of telemedicine included a lack of technological literacy, concerns with reimbursement, and resistance to changes in the workplace. In response to the COVID-19 pandemic declared in March 2020, the delivery of urological services globally has quickly shifted to telemedicine to account for the mass clinical, procedural, and operative cancellations, inadequate personal protective equipment, and shortage of personnel. OBJECTIVE: The aim of this study was to investigate current telemedicine usage by urologists, urologists' perceptions on the necessity of in-person clinic appointments, the usability of telemedicine, and the current barriers to its implementation. METHODS: We conducted a global, cross-sectional, web-based survey to investigate the use of telemedicine before and after the COVID-19 pandemic. Urologists' perceived usability of telemedicine was assessed using a modified Delphi approach to create questions based on a modified version of the validated Telehealth Usability Questionnaire (TUQ). For the purposes of this study, telemedicine was defined as video calls only. RESULTS: A total of 620 urologists from 58 different countries and 6 continents participated in the survey. Prior to COVID-19, 15.8% (n=98) of urologists surveyed were using telemedicine in their clinical practices; during the pandemic, that proportion increased to 46.1% (n=283). Of the urologists without telemedicine experience, interest in telemedicine usage increased from 43.7% (n=139) to 80.8% (n=257) during the COVID-19 pandemic. Among urologists that used telemedicine during the pandemic, 80.9% (n=244) were interested in continuing to use it in their practice. The three most commonly used platforms were Zoom, Doxy.me, and Epic, and the top three barriers to implementing telemedicine were patients' lack of technological comprehension, patients' lack of access to the required technology, and reimbursement concerns. CONCLUSIONS: This is the first study to quantify the use, usability, and pervading interest in telemedicine among urologists during the COVID-19 pandemic. In the face of this pandemic, urologists' usage of telemedicine nearly tripled, demonstrating their ability to adopt and adapt telemedicine into their practices, but barriers involving the technology itself are still preventing many from utilizing it despite increasing interest.

Assessment of readability, quality and popularity of online information on ureteral stents.

OBJECTIVE: To evaluate the quality and readability of online information on ureteral stents. METHODS: Google.com was queried using the search terms "ureteric stent", "ureteral stent", "double J stent" and, "Kidney stent" derived from Google AdWords. Website popularity was determined using Google Rank and the Alexa tool. Website quality assessment was performed using the following criteria: Journal of the American Medical Association (JAMA) benchmarks, Health on the Net (HON) criteria, and a customized DISCERN questionnaire. The customized DISCERN questionnaire was developed by combining the short validated DISCERN questionnaire with additional stent-specific items including definition, placement, complications, limitations, removal and "when to seek help". Scores related to stent items were considered as the "stent score" (SS). Readability was evaluated using five readability tests. RESULTS: Thirty-two websites were included. The mean customized DISCERN score and "stent score" were 27.1 ± 7.1 (maximum possible score = 59) and 14.6 ± 3.8 (maximum possible score = 24), respectively. A minority of websites adequately addressed "stent removal" and "when to seek medical attention". Only two websites (6.3%) had HON certification (drugs.com, radiologyinfo.org) and only one website (3.3%) met all JAMA criteria (bradyurology.blogspot.com). Readability level was higher than the American Medical Association recommendation of sixth-grade level for more than 75% of the websites. There was no correlation between Google rank, Alexa rank, and the quality scores (P > 0.05). DISCUSSION: Among the 32 most popular websites on the topic of ureteral stents, online information was highly variable. The readability of many of the websites was far higher than standard recommendations and the online information was questionable in many cases. These findings suggest a need for improved online resources in order to better educate patients about ureteral stents and also should inform physicians that popular websites may have incomplete information.

MicroRNA-1 is a candidate tumor suppressor and prognostic marker in human prostate cancer.

We previously reported that miR-1 is among the most consistently down-regulated miRs in primary human prostate tumors. In this follow-up study, we further corroborated this finding in an independent data set and made the novel observation that miR-1 expression is further reduced in distant metastasis and is a candidate predictor of disease recurrence. Moreover, we performed in vitro experiments to explore the tumor suppressor function of miR-1. Cell-based assays showed that miR-1 is epigenetically silenced in human prostate cancer. Overexpression of miR-1 in these cells led to growth inhibition and down-regulation of genes in pathways regulating cell cycle progression, mitosis, DNA replication/repair and actin dynamics. This observation was further corroborated with protein expression analysis and 3'-UTR-based reporter assays, indicating that genes in these pathways are either direct or indirect targets of miR-1. A gene set enrichment analysis revealed that the miR-1-mediated tumor suppressor effects are globally similar to those of histone deacetylase inhibitors. Lastly, we obtained preliminary evidence that miR-1 alters the cellular organization of F-actin and inhibits tumor cell invasion and filipodia formation. In conclusion, our findings indicate that miR-1 acts as a tumor suppressor in prostate cancer by influencing multiple cancer-related processes and by inhibiting cell proliferation and motility.

Quality of Information About Kidney Stones from Artificial Intelligence Chatbots.

Introduction: Kidney stones are common and morbid conditions in the general population with a rising incidence globally. Previous studies show substantial limitations of online sources of information regarding prevention and treatment. The objective of this study was to examine the quality of information on kidney stones from artificial intelligence (AI) chatbots. Methods: The most common online searches about kidney stones from Google Trends and headers from the National Institute of Diabetes and Digestive and Kidney Diseases website were used as inputs to four AI chatbots (ChatGPT version 3.5, Perplexity, Chat Sonic, and Bing AI). Validated instruments were used to assess the quality (DISCERN instrument from 1 low to 5 high), understandability, and actionability (PEMAT, from 0% to 100%) of the chatbot outputs. In addition, we examined the reading level of the information and whether there was misinformation compared with guidelines (5 point Likert scale). Results: AI chatbots generally provided high-quality consumer health information (median DISCERN 4 out of 5) and did not include misinformation (median 1 out of 5). The median understandability was moderate (median 69.6%), and actionability was moderate to poor (median 40%). Responses were presented at an advanced reading level (11th grade; median Flesch-Kincaid score 11.3). Conclusions: AI chatbots provide generally accurate information on kidney stones and lack misinformation; however, it is not easily actionable and is presented above the recommended reading level for consumer health information.

Plant-based diets and urological health.

Plant-based diets have grown in popularity owing to multiple health and environmental benefits. Some evidence suggests that plant-based diets are associated with benefits for urological health. In genitourinary oncology, most research has focused on prostate cancer. Clinical trial results suggest a favourable influence of healthy lifestyle modifications including plant-based diets before and after prostate cancer treatment. Epidemiological evidence shows that a diet higher in plant-based and lower in animal-based food is associated with a lower risk of aggressive prostate cancer and better quality-of-life scores than a diet with less plant-based and more animal-based food. Studies on bladder and kidney cancer are scarce, but limited data suggest that vegetarian or plant-forward dietary patterns (increased consumption of fruits and vegetables and minimizing meat) are associated with a lower risk of development of these cancers than dietary patterns with fewer fruits and vegetables and more meat. With respect to benign urological conditions, epidemiological studies suggest that plant-based dietary patterns are associated with a lower risk of benign prostatic hyperplasia and urinary tract infections than non-plant-based dietary patterns. Compared with diets high in animal-based foods and low in plant-based foods, a substantial body of epidemiological evidence also suggests that increased consumption of healthy plant-based food is associated with a lower risk of erectile dysfunction. Plant-based dietary patterns that are high in fruits and vegetables with normal calcium intake, while limiting animal protein and salt, are associated with a lower risk of kidney stone development than dietary patterns that do not follow these parameters. Overall, increasing consumption of plant-based foods and reducing intake of animal-based foods has favourable associations with multiple urological conditions.

Systematic review of the impact of a plant-based diet on prostate cancer incidence and outcomes.

BACKGROUND: Plant-based diets are increasingly popular and have many well-established benefits for health and environmental sustainability. Our objective was to perform a systematic review of plant-based diets and prostate cancer. METHODS: We performed a systematic database and citation search in February 2022. Studies were included if they reported primary data on plant-based dietary patterns (i.e., vegan, vegetarian, plant-based) and incidence among at-risk men for prostate cancer, or oncologic, general health/nutrition, or quality of life outcomes among patients with prostate cancer or caregivers. RESULTS: A total of 32 publications were eligible for the qualitative synthesis, representing 5 interventional and 11 observational studies. Interventional studies primarily focused on lifestyle modification including plant-based diets for men on active surveillance for localized prostate cancer or with biochemical recurrence after treatment, showing improvements in short-term oncologic outcomes alongside improvements in general health and nutrition. Observational studies primarily focused on prostate cancer risk, showing either protective or null associations for plant-based dietary patterns. Studies of the vegan diet consistently showed favorable associations with risk and/or outcomes. Gaps in the current literature include impact for long-term disease-specific outcomes. CONCLUSIONS: Interventional studies showed generally favorable results of lifestyle modifications incorporating a plant-based diet with prostate cancer outcomes as well as improvements in nutrition and general health. Observational studies demonstrated either a lower risk of prostate cancer or no significant difference. These results are encouraging in light of the many benefits of plant-based diets for overall health, as well as environmental sustainability and animal welfare.

Laparoscopic partial nephrectomy: six degrees of haemostasis.

OBJECTIVE: • To describe six steps for haemostasis and collecting system closure ('six degrees of haemostasis') that are reproducible and that minimize the two most concerning complications of laparoscopic partial nephrectomy: haemorrhage and urine leakage. METHODS: • A retrospective study of 23 consecutive laparoscopic partial nephrectomy cases performed by a single surgeon between 2005 and 2008 using the 'six degrees of haemostasis' was carried out. RESULTS: • There were no cases of intraoperative, postoperative or delayed bleeding. • There were no cases of urine leakage. CONCLUSION: • The 'six degrees of haemostasis' technique for laparoscopic partial nephrectomy described in the present study provides a reliable and reproducible method to reassure the surgeon of haemostasis and provide a decreased risk of urine leakage.

Outcomes and peri-operative complications of robotic pyelolithotomy.

Standard of care for large or complex renal stones is percutaneous nephrolithotomy. Robotic pyelolithotomy, however, may be a feasible alternative, but limited data exist on its outcomes and complications. Our study objective was to describe the outcomes and peri-operative complications of robotic pyelolithotomy for complex renal calculi. We performed a retrospective analysis of robotic pyelolithotomy at our tertiary academic institution from 2015 to 2018. Demographics, stone clearance rates, complications, estimated blood loss, operative time, and length of stay were reported. 15 patients were included with a median age of 59 years (SD 15.3, 27-80) and BMI 25 kg/m2 (SD 4.6, 20.9-35.7). Median follow-up was 4 months. Median stone size was 3 cm (SD 1.2 cm, 2-5 cm). Concomitant pyeloplasty was performed in 2 patients, complete stone clearance in 11 (73%) cases and 4 out of 5 (80%) with a solitary stone. Median operative time was 191.5 min (SD 64.8 min, 110-303 min), with no open conversion. Median EBL was 70 ml (SD 65 ml, 20-250 ml) and median length of stay was 1 day (SD 1 day, 1-5 days). Median change in creatinine and eGFR were - 0.02 mg/dl and + 3 ml/min/1.73 m2. There were no cases of sepsis or post-operative fever and only one case of transfusion. Robotic pyelolithotomy appears safe and effective. Ultimately, less bleeding, lower septicemia, renal parenchymal preservation, and favorable stone-free rates in a single procedure make this as an attractive option in the management of select patients with large renal stone disease.

Fake News: Spread of Misinformation about Urological Conditions on Social Media.

Although there is a large amount of user-generated content about urological health issues on social media, much of this content has not been vetted for information accuracy. In this article, we review the literature on the quality and balance of information on urological health conditions on social networks. Across a wide range of benign and malignant urological conditions, studies show a substantial amount of commercial, biased and/or inaccurate information present on popular social networking sites. The healthcare community should take proactive steps to improve the quality of medical information on social networks. PATIENT SUMMARY: In this review, we examined the spread of misinformation about urological health conditions on social media. We found that a significant amount of the circulating information is commercial, biased or misinformative.

Comparative study of in vivo lymphatic sealing capability of the porcine thoracic duct using laparoscopic dissection devices.

PURPOSE: Sealing the lymphatic vessels during abdominal and pelvic surgery is important to prevent the leakage of lymphatic fluid and its resultant sequelae. To our knowledge we compared for the first time the quality of lymphatic sealing by each of 4 commonly used laparoscopic dissection devices. MATERIALS AND METHODS: A total of 12 domestic pigs were used to test dissecting devices, including monopolar scissors (Ethicon Endo-Surgery, Cincinnati, Ohio), Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector. A midline incision was made from mid sternum to umbilicus, the diaphragm was divided and the porcine thoracic duct was isolated. In all animals each device was used to seal an area of the duct and each seal was placed at least 2 cm from the prior seal. In group 1 the thoracic duct of 6 pigs was cannulated with a 5Fr catheter and the seal was subjected to burst pressure testing using a burst pressure measuring device (Cole-Parmer, Vernon Hills, Illinois). In the 6 pigs in group 2 each seal was immediately sent for histopathological evaluation. Specimens were given a score for the extent of cautery damage, including 0-none, 1-minimal, 2-moderate, 3-severe and 4-extreme. RESULTS: A total of 64 seals were created, of which 35 were subjected to burst pressure testing. Mean size of the thoracic duct was 2.6 mm. No acute seal failures were observed with any bipolar device or the harmonic shears. However, 2 immediate failures (33%) were seen with monopolar scissors. Mean burst pressure for monopolar scissors, Harmonic ACE Scalpel, LigaSure V, EnSeal and Trissector was 46 (range 0 to 165), 540 (range 175 to 795), 258 (range 75 to 435), 453 (range 255 to 825) and 379 mm Hg (range 175 to 605), respectively (p <0.05). Trissector, Harmonic ACE Scalpel and EnSeal generated seals with significantly higher burst pressure than that of monopolar scissors (p <0.05). Histopathological evaluation revealed that LigaSure caused less thermal damage than Trissector and EnSeal (p <0.05). CONCLUSIONS: Each device tested except monopolar scissors consistently produced a supraphysiological seal and should be suitable for sealing lymphatic vessels during laparoscopic surgery.

The 'buoy' stent: evaluation of a prototype indwelling ureteric stent in a porcine model.

OBJECTIVE To assess a prototype ureteric 'buoy' stent with a 10 F upper body tapering to a 3F tail, developed to potentially reduce stent-related irritative symptoms while providing an adequate mould for healing after endopyelotomy. MATERIALS AND METHODS Eighteen Yucatan minipigs had the stent placed either into the intact ureter (phase I) or after Acucise proximal endoureterotomy (phase II). Buoy stents were compared to 10/7 F endopyelotomy stents and to standard 7 F stents in phases I and II, respectively. The pigs were assessed for vesico-ureteric reflux, hydronephrosis and infection, before stent insertion and at harvest. Stents were weighed before and after placement and the removal force was measured. Pressure/flow studies, antegrade nephrostograms and specimens for histopathology from the renal pelvis, ureter and vesico-ureteric junction (VUJ) were obtained at harvest. RESULTS Thirteen minipigs survived the entire study. Ureteric flow with the stents in situ was better for buoy stents than for 10/7 F stents (P < 0.005). Ureteric flow after endoureterotomy and subsequent stent removal was similar for buoy stents and standard 7 F stents. None of the stents refluxed. There was no difference between stents in removal force, weight change or incidence of hydronephrosis. At 1 and 12 weeks, buoy stents tended to produce lower histopathological alteration scores than control stents, especially at the VUJ (phase I, 2.0 vs 3.9, P = 0.092; phase II, 0.6 vs 1.7, P = 0.18). CONCLUSIONS The novel buoy stents are easily placed and removed via the urethra. They can cause less VUJ inflammation than standard stents while allowing for adequate ureteric flow and healing after proximal endoureterotomy.

Comparison of healing after cystotomy and repair with fibrin glue and sutured closure in the porcine model.

PURPOSE: We compared healing after laparoscopic cystotomy using fibrin glue, sutures, or a combination to determine whether fibrin glue can obviate the need for sutures and whether there is any detriment when glue is used in the presence of sutures. MATERIALS AND METHODS: In 24 Yorkshire pigs, a 3.5 cm vertical cystotomy was created laparoscopically and repaired as follows: Group 1--no closure; group 2--fibrin glue closure; group 3--suture repair; group 4--combined fibrin glue and suture repair. All animals had a Foley catheter for 1 week. In each group, three animals were harvested at 1 week (acute) and three animals were harvested at 6 weeks (chronic). RESULTS: Acute: Group 1--all pigs had an unhealed defect that leaked when evaluated by cystography. Groups 2, 3, 4--mean leak pressures were 80, 97, and 60 cm H(2)O (P = 0.36), respectively. Mean bladder capacity was not significantly different between groups. Chronic: No leakage seen on a cystogram at 1 week; at 6 weeks, bladders were filled at > or =95 to 100 cm H(2)O without leakage. Histologically, there was more inflammation in the acute group v chronic group pigs. In the acute group pigs repaired with glue or suture + glue, there was more inflammation and less epithelial continuity than in the suture alone group. At 6 weeks, there was no difference between groups. CONCLUSION: Fibrin glue provoked an intense inflammatory response that might have delayed healing acutely, resulting in a lower burst pressure in both scenarios in which it was used (i.e., alone or in combination with sutures). However, by 6 weeks, there did not seem to be any difference between groups either clinically or histopathologically.

Robotic versus standard laparoscopic partial/wedge nephrectomy: a comparison of intraoperative and perioperative results from a single institution.

PURPOSE: Laparoscopic partial/wedge nephrectomy, similar to laparoscopic radical prostatectomy, is a technically challenging procedure that is performed by a limited number of expert laparoscopic surgeons. The incorporation of a robotic surgical interface has dramatically increased the use of minimally invasive pelvic surgery such that robotic laparoscopic radical prostatectomy is commonly performed even by laparoscopically naïve surgeons. This analysis compares the outcomes of our initial experience with robot-assisted laparoscopic partial nephrectomy (RLPN) performed by an experienced open surgeon to that of standard laparoscopic partial nephrectomy (LPN) performed by two experienced laparoscopic surgeons. PATIENTS AND METHODS: We reviewed the medical records of 11 consecutive patients who underwent 12 standard LPNs (EMM, RVC) (one patient had two unilateral tumors) and 10 consecutive patients (representing the first 11 of such robotic procedures performed at our institution) who underwent 11 RLPNs (one patient had bilateral tumors managed in an asynchronous manner) (DKO). RESULTS: The mean tumor size was 2.3 cm (range 1.7-6.2 cm) for LPN and 3.1 cm (range 2.5-4 cm) for RLPN. The mean total procedure time was 289.5 minutes (range 145-369 min) for LPN and 228.7 minutes (range 98-375 min) for RLPN (P=0.102). The mean estimated blood loss was 198 mL (range 75-500 mL) for LPN v 115 mL (25-300 mL) for RLPN (P=0.169). The mean warm ischemia time was 35.3 minutes (range 15-49 min) in the LPN group and 32.1 minutes (range 30-45 minutes) in the RLPN group (P=0.501). CONCLUSIONS: Introducing a robotic interface for laparoscopic partial/wedge resection allowed a fellowship-trained urologic oncologist with limited reconstructive laparoscopic experience to achieve results comparable to those for laparoscopic partial/wedge resection performed by experienced laparoscopic surgeons. In this regard, the learning curve appears truncated, similar to that with robot-assisted laparoscopic prostatectomy.

Preoperative cystoscopy is beneficial in selection of patients for laparoscopic repair of intraperitoneal bladder rupture.

Intraperitoneal bladder rupture usually is caused by blunt external trauma to a distended bladder. Although such injuries generally necessitate a formal laparotomy, advances in minimally invasive surgery have allowed successful laparoscopic repair. We describe our preoperative evaluation and laparoscopic technique in a case of isolated intraperitoneal bladder rupture secondary to trauma.

In-vivo evaluation of flow characteristics of novel metal ureteral stent.

PURPOSE: To characterize the flow of a novel ureteral stent composed of a nickel-cobalt-chromium-molybde-num alloy and compare it with flow in a standard ureteral stent. MATERIALS AND METHODS: Six 6F Resonance stents and six 6F standard Black Beauty ureteral stents were placed in six Yucatan minipigs, with each pig serving as its own control. Flow assessment was performed on all stents via a nephrostomy tube delivering a standard rate of 0.9% saline at 35 cm H(2)O. Flow studies on the standard stents encompassed extraluminal (i.e., lumen of stent occluded with a guidewire), intraluminal (i.e., ureter secured to stent with a constricting suture), and combined (i.e., open lumen without constricting suture) flow. In the Resonance stent, only combined and intraluminal flow could be addressed, as there is no access to the lumen of this stent. RESULTS: With the Resonance stent, intraluminal flow was much greater than combined flow, with mean values of 5.15 mL/min and 2.50 mL/min, respectively (P = 0.057; SD = 7.73). Intraluminal flow was similar to combined flow in the 6F standard stent, with mean values of 7.34 mL/min and 7.30 mL/min, respectively (P = 0.88; SD = 1.76). The standard stent had significantly greater combined flow than the Resonance stent (P = 0.023) but not intraluminal flow (P = 0.247). Of note, whereas it was possible to occlude the 6F standard stent completely with a ureteral ligature (i.e., no guidewire placed in the lumen), it was not possible to occlude the Resonance stent regardless of how tightly the suture was tied. CONCLUSION: The Resonance metal alloy stent provides less overall flow than a standard stent. However, under circumstances of extrinsic ureteral compression sufficient to occlude a standard stent (e.g., extrinsic compression plus an internal guidewire), the metal stent continues to provide satisfactory drainage.

Rapid communication: effects of Steris 1 sterilization and Cidex ortho-phthalaldehyde high-level disinfection on durability of new-generation flexible ureteroscopes.

BACKGROUND AND PURPOSE: The effects of commonly used reprocessing methods on flexible ureteroscope longevity have never been examined. We prospectively studied the effects of Steris 1 sterilization and Cidex ortho-phthalaldehyde (OPA) high-level disinfection (HLD) on the image quality, physical structure, and deflective properties of two new flexible ureteroscopes. MATERIALS AND METHODS: Two identical "out-of-the-box" Storz 11278AU1 flexible ureteroscopes (Karl Storz Endoscopy, Tuttlingen, Germany) were sterilized individually using the Steris 1 system (Steris Mentor, Ohio) or disinfected with Cidex OPA (Advanced Sterilization Products, J&J, Irvine, CA) for 100 trials followed by a crossover to the other method for another 100 trials over a period of 1 year. After every five trials, optical quality, angle of deflection, and fiber damage were analyzed in the laboratory. Throughout the study, neither of these ureteroscopes was used clinically. RESULTS: After 100 trials, ureteroscope 1, which was sterilized initially in the Steris system, had a 12-mm tear on its shaft (noted after the 17th trial), 297 damaged fibers, and a 37% drop in resolution (loss of 3.75 lines/mm). There was no change in deflection from baseline. In contrast, after 100 cycles, ureteroscope 2, which was subjected to HLD with Cidex OPA, had no visible external damage, a 0% change in resolution, 10 damaged fibers, and no change in deflection. After the crossover, ureteroscope 2 developed a semilunar defect that obscured the endoscopic view, whereas there was no further significant damage to ureteroscope 1. CONCLUSION: After 100 cycles, the Steris 1 system rendered the flexible ureteroscope unusable, whereas HLD with Cidex OPA had minimal adverse impact.

3D printed renal cancer models derived from MRI data: application in pre-surgical planning.

OBJECTIVE: To determine whether patient-specific 3D printed renal tumor models change pre-operative planning decisions made by urological surgeons in preparation for complex renal mass surgical procedures. MATERIALS AND METHODS: From our ongoing IRB approved study on renal neoplasms, ten renal mass cases were retrospectively selected based on Nephrometry Score greater than 5 (range 6-10). A 3D post-contrast fat-suppressed gradient-echo T1-weighted sequence was used to generate 3D printed models. The cases were evaluated by three experienced urologic oncology surgeons in a randomized fashion using (1) imaging data on PACS alone and (2) 3D printed model in addition to the imaging data. A questionnaire regarding surgical approach and planning was administered. The presumed pre-operative approaches with and without the model were compared. Any change between the presumed approaches and the actual surgical intervention was recorded. RESULTS: There was a change in planned approach with the 3D printed model for all ten cases with the largest impact seen regarding decisions on transperitoneal or retroperitoneal approach and clamping, with changes seen in 30%-50% of cases. Mean parenchymal volume loss for the operated kidney was 21.4%. Volume losses >20% were associated with increased ischemia times and surgeons tended to report a different approach with the use of the 3D model compared to that with imaging alone in these cases. The 3D printed models helped increase confidence regarding the chosen operative procedure in all cases. CONCLUSIONS: Pre-operative physical 3D models created from MRI data may influence surgical planning for complex kidney cancer.