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Tal Amitay-Rosen,1 Ishai Dror,2 Yaniv Shilo,3 Brian Berkowitz2 1Department of Physical Chemistry, Institute for Biological Research, Ness-Ziona, 7410001, Israel; 2Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel; 3Department of Urology, Kaplan Medical Center, Affiliated with the Hebrew University of Jerusalem, Rehovot, 7661041, IsraelCorrespondence: Brian Berkowitz, Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot, 7610001, Israel, Tel +972-8-9342098, Fax +972-8-9344124, Email brian.berkowitz@weizmann.ac.ilIntroduction: Ureteral stents are effective in alleviating flow disruptions in the urinary tract, whether due to ureteral stones, strictures or extrinsic ureteral obstruction. However, significant stent encrustation on the external and/or internal stent lumen walls can occur, which may interfere with stent functioning and/or removal. Currently, there is only limited, generally qualitative, information on the distribution, mineral structure, and chemical content of these deposits, particularly in terms of stent lumen encrustation.Objective: To quantify, in an initial investigation, external and internal encrustation in representative, intact ureteral stents. The study investigates possible correlations between patterns of external and internal encrustation, determines mineral structure and chemical composition, and examines the potential for stent lumen obstruction even in the absence of external stent wall encrustation.Study Design: High-resolution, laboratory micro-computed tomography (micro-CT) was used to non-destructively image external and internal stent encrustation in four representative stents. X-ray diffractometry (XRD) and scanning electron microscopy–energy dispersive x-ray spectroscopy (SEM-EDS) enabled parallel analysis of mineral structure and chemical content of samples collected from external and internal encrusted material along the distal, proximal and mid-ureteral stent regions.Results: Extensive stent lumen encrustation can occur within any region of a stent, with only incidental or minor external encrustation, along the entire length of the stent. External and internal encrusted materials in a given stent are generally similar, consisting of a combination of amorphous (mostly organic) and crystalline mineral deposits.Conclusion: Micro-CT demonstrates that significant stent lumen encrustation can occur, which can lead to partial or full stent lumen occlusion, even when the exterior stent wall is essentially free of encrusted material.Keywords: micro-computed tomography, stent deposition, mineral composition, obstruction, stent lumen

August 2006 marked the 10th anniversary of landmark legislation when Israel's parliament passed the unique Patient's Rights Law. This law underscores the importance of medical ethics in Israeli society. During a seminar at the Shaare Zedek School of Nursing, third-year students performed a qualitative research study investigating ethical issues arising in the field of nursing, and how nursing staff dealt with these issues in relation to the law. The research was conducted using semistructured questionnaires. The results showed that the staff participants knew the law, but did not differentiate between legal and ethical problems. The establishment of a framework for dealing with these issues would help to promote professional ethics, encourage broad-based agreements related to ethical decisions, reduce ethical conflict, and increase implementation of the law on patients' rights. [ABSTRACT FROM AUTHOR]

Tramadol is a centrally acting analgesic drug that has been used clinically for the last two decades to treat moderate to moderately severe pain in humans. The present study investigated tramadol administration in horses by intravenous, intramuscular, oral as immediate-release and oral as sustained-release dosage-form routes. Seven horses were used in a four-way crossover study design in which racemic tramadol was administered at 2 mg/kg by each route of administration. Altogether, 23 blood samples were collected between 0 and 2880 min. The concentration of tramadol and its M1 metabolite were determined in the obtained plasma samples by use of an LC/MS/MS method and were used for pharmacokinetic calculations. Tramadol clearance, apparent volume of distribution at steady-state, mean residence time ( MRT) and half-life after intravenous administration were 26 ± 3 mL/min/kg, 2.17 ± 0.52 L/kg, 83 ± 10 min, and 82 ± 10 min, respectively. The MRT and half-life after intramuscular administration were 155 ± 23 and 92 ± 14 min. The mean absorption time was 72 ± 22 min and the bioavailability 111 ± 39%. Tramadol was poorly absorbed after oral administration and only 3% of the administered dose was found in systemic circulation. The fate of the tramadol M1 metabolite was also investigated. M1 appeared to be a minor metabolite in horses, which could hardly be detected in plasma samples. The poor bioavailability after oral administration and the short half-life of tramadol may restrict its usefulness in clinical applications. [ABSTRACT FROM AUTHOR]

Background: Compliance with the guideline recommendations for neoadjuvant chemotherapy in patients with muscle-invasive bladder cancer is incomplete. The adjuvant chemotherapy approach has the advantage of pathology-based decision-making, allowing for patient selection. In addition, radical surgery is not delayed and treatment-related toxicity does not impair surgical fitness. The proportion of patients who completed chemotherapy after cystectomy among those who were fit and in need of treatment were evaluated. The reasons for not completing adjuvant chemotherapy were determined., Materials and Methods: We retrospectively evaluated all patients who had undergone radical cystectomy at our center over the last 7 years. Indications for adjuvant chemotherapy included pathological T > 2, any node+, or surgical margin involvement. Only patients who were fit for chemotherapy before surgery were included in the study., Results: Of the 52 patients with muscle-invasive bladder cancer, 14 received neoadjuvant chemotherapy or unfit for chemotherapy were excluded. Of the remaining 38 patients, 14 (37%) had bladder-confined cancers and did not require additional chemotherapy. Of the 24 patients who needed chemotherapy and were fit to receive it, 8 patients completed treatment (33%), and 3 discontinued treatment due to toxicity. Twelve patients (50%) declined chemotherapy, whereas 1 patient became unfit for chemotherapy after surgery., Conclusions: While the adjuvant chemotherapy approach could save unnecessary treatment in 37% of patients, two-thirds of those who needed chemotherapy did not complete it. Patient refusal was the primary reason for not receiving treatment., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc.)

Urolithiasis is a frequent disease with cited rates of recurrence after initial diagnosis that vary widely and range between 35% and 50%. We assessed the radiographic recurrence rate in patients with urinary stones and its risk factors. We retrospectively identified patients who were diagnosed with urinary stones on non-contrast computed tomography from 2010 to 2011, and underwent another imaging examination at least six months afterwards. We collected patient demographic, clinical, laboratory and radiologic data and compared patients with and without urinary stone recurrence. Ultimately, 237 patients were included in the study; the mean follow-up was 6.7 years; 88 patients (37.1%) had recurrence based on our recurrence criteria. On univariate analysis, the significant parameters for recurrence were baseline serum calcium and uric acid, stone location in the kidney, surgical intervention and stone burden volume. On multivariate analysis, surgical intervention (OR 3.07, p = 0.001), baseline calcium (OR 2.56, p = 0.011), baseline uric acid (OR 1.30, p = 0.021) and stone location in the kidney (OR 2.16, p = 0.012) were associated with higher risk of recurrence. These findings may guide personalized follow-up protocols for patients with urolithiasis based on their risk factors.

Objective: To quantify the relative volumetric flows in stent and ureter lumina, as a function of stent size and configuration, in both unobstructed and externally obstructed stented ureters., Methods: Magnetic resonance imaging was used to measure flow in stented ureters using a phantom kidney model. Volumetric flow in the stent and ureter lumina were determined along the stented ureters, for each of four single stent sizes (4.8F, 6F, 7F, and 8F), and for tandem (6F and 7F) configurations. Measurements were made in the presence of a fully encircling extrinsic ureteral obstruction as well as in benchmark cases with no extrinsic ureteral obstruction., Results: Under no obstruction, the relative contribution of urine flow in single stents is 1-10%, while the relative contributions to flow are ~6 and ~28% for tandem 6F and 7F, respectively. In the presence of an extrinsic ureteral obstruction and single stents, all urine passes within the stent lumen near the extrinsic ureteral obstruction. For tandem 6F and 7F stents under extrinsic ureteral obstruction, relative volumetric flows in the two stent lumina are ~73% and ~81%, respectively, with the remainder passing through the ureter lumen., Conclusions: Magnetic resonance imaging demonstrates that with no extrinsic ureteral obstruction, minimal urine flow occurs within a stent. Stent lumen flow is significant in the presence of extrinsic ureteral obstruction, in the vicinity of the extrinsic ureteral obstruction. For tandem stents subjected to extrinsic ureteral obstruction, urine flow also occurs in the ureter lumen between the stents, which can reduce the likelihood of kidney failure even in the case of both stent lumina being occluded., (© 2022 The Authors. International Journal of Urology published by John Wiley & Sons Australia, Ltd on behalf of The Japanese Urological Association.)

Most patients with ureterolithiasis are managed successfully with conservative treatment. In this context, delineation of clinical risk factors that identify patients with low risk for surgical intervention may reduce use of Non-Contrast Computed Tomography (NCCT). Here, emergency department patient files from a 14-month period were reviewed retrospectively, to identify patients who underwent NCCT and showed a ureteral stone. Demographic, clinical and laboratory information was collected. Patients were grouped to either requiring surgical intervention (Group 1) or having successful conservative management (Group 2). The cohort included 368 patients; 36.1% ultimately required surgical intervention (Group 1) and 63.9% were successfully treated conservatively (Group 2). On univariate analysis, patients who required surgical intervention were older, had longer duration of symptoms, had history of urolithiasis and surgical intervention for urolithiasis and had higher serum creatinine levels. Multivariate analysis identified the following risk factors associated with surgical intervention: creatinine >1.5 mg/dL, duration of symptoms ≥ 1.5 days and age > 45 years. Patients with 0, 1, 2 or 3 of the identified risk factors had 19%, 32%, 53% and 73% likelihood, respectively, of surgical intervention. Incorporating these data may reduce the use of NCCT scans in patients who are likely to pass a stone via conservative management.

Purpose: The purpose of our study was to evaluate the ability of ureteral stents with different diameters to drain pus that accumulates in an obstructed kidney using an in vitro model., Methods: We developed an in vitro model of an obstructed kidney filled with pus. The model included a silicon kidney unit based on computed tomography (CT) data, a 3D printed ureteral stone based on a real extracted ureteral stone, a latex ureter model, a bladder vessel, and a fluid with qualities resembling pus. Identical printed stones were inserted into four ureter models containing stents with varying diameters (4.8F, 6F, 7F, 8F), each of which was connected to the kidney unit and the bladder vessel. The kidney unit was filled with artificial pus to pressures of 30 cmH 2 O to simulate an infected and obstructed kidney. The obstruction was relieved with stents in place, while artificial urine was pumped into the kidney; pressure in the kidney and remaining pus were measured continuously., Results: The rate of pressure drop and the final pressure measured in the kidney were unaffected by the diameter of the stent. For all stent diameters, the pressure reached non-obstructed levels within 30 s, final pressure was reached within 90-120 s, and minimal amounts of pus remained in the kidney after 120 min., Conclusions: In vitro experiments demonstrate that all stent diameters drain pus-filled, obstructed kidneys with the same efficacy. The common perception that larger diameter tubes are more effective under such circumstances should be re-examined., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Ureteral stents are employed regularly to facilitate urine drainage and ureteral healing in a wide variety of endourological procedures, associated mainly with ureteral stone obstruction. However, stent use frequently impairs patient quality of life, which is generally attributed to the presence of anchoring stent curls in the bladder and/or kidney. The purpose of this study was to examine the potential effectiveness and safety of a newly designed, fully intraureteral stent, in an initial proof-of-concept in vivo evaluation., Methods: "Yoticurl" stents were synthesized from copolymeric, commercially-available ureteral stents. A first test to confirm the intended expansion of the spiral curls in a ureter was performed on a pig cadaver. Subsequently, a preliminary in vivo evaluation in a single pig model was completed to test stent viability, over a period of 25 days. Two stents were inserted to fully intraureteral positions into the two ureters, by standard human endourological procedure. Daily observational checks of the pig, and regular radiographic analyses were performed; the animal was then euthanized and examined by explorative laparotomy, followed by histological analysis of kidney, ureter and bladder tissue samples., Results: The pig displayed normal activity, appetite and sleep patterns, and radiography indicated free flow of urine, and no significant stent migration nor anatomical abnormalities. Subsequent histology found only mild inflammation in the ureter., Conclusions: The innovative stent design tested here, if ultimately proven safe and effective for human use, may offer an alternative to currently available stents for multiple indications., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tau.amegroups.com/article/view/10.21037/tau-22-41/coif). YS and BB are co-inventors of a patent application (PCT/IB2021/052274), relating to aspects of this ureteral stent and/or its use, submitted jointly by Yeda Research & Development Co., Ltd. and Mor Research Applications Ltd., Israel. BB holds the Sam Zuckerberg Professorial Chair in Hydrology. The other author has no conflicts of interest to declare., (2022 Translational Andrology and Urology. All rights reserved.)

Background: Proximal ureteral stones (PUS) have relatively low rates of spontaneous expulsion. However, some patients do well on expectant management. Our aim was to compare risk factors for surgical intervention in patients with PUS who underwent primary intervention to those subjected to expectant management., Materials and Methods: We retrospectively reviewed the medical charts of patients presented to the emergency room with symptoms of renal colic and underwent computerized tomography between August 2016 and August 2017. A total of 97 consecutive patients were identified with up to 10mm PUS. We collected patient demographics, clinical, and imaging data, and performed binary regression analysis for risk of intervention., Results: The average age was 49years (range 17-97) and average stone size was 7.1mm (range 3-10). Forty-one patients underwent immediate intervention while the remaining 56 patients were treated conservatively. Of the 56 patients treated conservatively, 26 underwent delayed intervention while 30 reported spontaneous stone expulsion. On univariate analysis of all 97 patients, statistically significant risk factors for intervention were found based on stone size, age, serum lymphocyte, platelet counts, and stone density. Of these risk factors, stone size ≥ 7mm ( p = 0.012, odds ratio = 5.4) and platelet count ≤ 230K/μL ( p = 0.027, odds ratio = 4.9) remained statistically significant on multivariate analysis., Conclusion: Stone size and platelet count were found to be risk factors for surgical intervention in patients with up to 10mm PUS. These findings may assist in identifying patients who are more suitable for conservative approach., Competing Interests: The authors report no conflicts of interest., (Copyright © 2022 The Authors. Published by Wolters Kluwer Health, Inc.)

Background and Purpose: Drainage of obstructed kidney attributable to extrinsic ureteral obstruction (EUO), required to prevent renal damage, is often achieved using Double-J ureteral stents. However, these stents fail frequently, and there is considerable debate regarding what stent size, type, and configuration offer the best option for sustained drainage. In this study, we examine the impact of stent diameter and choice of single/tandem configuration, subject to EUO and various degrees of stent occlusion, on stent failure. Materials and Methods: Computational fluid dynamics simulations and an in vitro ureter-stent experiment enabled quantification of flow behavior in stented ureters subject to EUO and stent occlusions. Various single and tandem stents under EUO were considered. In each simulation and experiment, changes in renal pressure were monitored for different degrees of stent lumen occlusion, and onset of stent failure as well as simulated distributions of fluid flow between stent and ureter lumina were determined. Results: For an encircling EUO that completely obstructs the ureter lumen, with or without partial stent occlusion, the choice of stent size/configuration has little effect on renal pressure. The pressure increases significantly for ∼90% stent lumen occlusion, with failure at >95% occlusion, independent of stent diameter or a tandem configuration, and with little influence of occlusion length along the stent. Conclusions: Stent failure rate is independent of stent diameter or single/tandem configuration, for the same percentage of stent lumen occlusion, in this model. Stent failure incidence may decrease for larger diameter stents and tandem configurations, because of the larger luminal area.

Background: Patients with high-risk prostate cancer are at higher risk of treatment failure, development of metastatic disease, and mortality. There is no consensus on the treatment of choice for these patients, and either radical prostatectomy (RP) or external beam radiation therapy (EBRT) is recommended. Surgery is less common as the initial treatment for high-risk patients, possibly reflecting the concerns regarding morbidity as well as oncological and functional outcomes. Another high-risk group includes patients with failure of previous EBRT or focal treatment. For these patients, salvage radical prostatectomy (SRP) can be offered., Objectives: To describe our experience with surgery of high-risk patients and SRP., Methods: This cohort included all high-risk patients undergoing RP or SRP at our institution between January 2012 and December 2019. We reviewed the electronic medical charts and collected pathological, functional, and oncological outcomes., Results: Our cohort included 39 patients; average age was 67.8 years, and average follow-up duration was 40.9 months. The most common postoperative morbidity was transfusion of packed cells. There were no life-threatening events or postoperative mortality. Continence was preserved (zero to one pad) in 76% of the patients. Twenty-three patients (59%) had undetectable prostate specific antigen levels following the surgery, 11 (30%) were treated with either adjuvant or salvage EBRT, and 12 patients (31%) were found with no evidence of disease and no additional treatment was needed., Conclusions: Radical prostatectomy and SRP are safe options for patients presenting with high-risk prostate cancer, with good functional and oncological outcomes.

Background: Radical cystectomy is a complicated surgery with significant risks. Complications of Clavien-Dindo grade 3-4 range from 25% to 40% while risk of mortality is 2%. Pelvic surgery or radiotherapy prior to radical cystectomy increases the challenges of this surgery., Objectives: To assess whether radical cystectomy performed in patients with prior history of pelvic surgery or radiation was associated with increased frequency of Clavien-Dindo grade 3 or higher complications compared to patients without prior pelvic intervention., Methods: We retrospectively evaluated all patients who underwent radical cystectomy at our center over a 7-year period. All patients with pelvic radiation or surgery prior to radical cystectomy comprised group 1, while group 2 included the remaining patients., Results: In our study, 65 patients required radical cystectomy at our institution during the study period. Group 1 was comprised of 17 patients and group 2 included 48 patients. Four patients from group 2 received orthotopic neobladder, while an ileal conduit procedure was performed in the remaining patients. Estimated blood loss and the amount of blood transfusions given was the only variable found to be statistically different between the two groups. One patient from group 1 had four pelvic interventions prior to surgery, and her cystectomy was aborted., Conclusions: Radical cystectomy may be safely performed in patients with a history of pelvic radiotherapy or surgery, with complication rates similar to those of non-irradiated or operated pelvises.

Purpose: To quantify the occurrence of stent failure and the dynamic behavior of urine flow in ureter-stent systems, including the relative flow in the ureter and stent lumina, subject to various degrees of ureter and stent blockage., Methods: Numerical simulations based on computational fluid dynamics (CFD) were used to quantify urine flow behavior in stented ureters, in the presence of extrinsic ureteral obstruction (EUO) and stent occlusions. Two stented ureter configurations were considered, one with circumferential occlusion of the ureter and the second with pressure on one side of the ureter wall. The pressure within the renal unit for different degrees of ureter closure and stent lumen occlusion was determined systematically. Onset of stent failure and the distribution of urine flow between stent and ureter lumina were determined., Results: In the case of EUO completely encircling the ureter, causing 100% obstruction of the ureter lumen, pressure in the renal unit is essentially unaffected until the stent lumen reaches ~ 90% occlusion, and fails only with > 95% occlusion. Occlusions of 50% in stent side holes in the vicinity of the EUO only alter local flow patterns but have no significant influence on renal unit pressure. For EUO deforming and compressing the ureter from one side, with ~ 50% reduction in ureter lumen, urine drainage proceeds with negligible increase in renal pressure even with 100% occlusion in the stent lumen., Conclusion: CFD simulations show that stent failure under EUO tends to occur suddenly, only when both ureter and stent lumina become almost fully blocked., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V. part of Springer Nature.)

Background: To compare the efficacy of different ureteral stents subject to extrinsic ureteral obstruction (EUO), in a controlled in vitro stented ureter experiment., Methods: We employ an in vitro ureter-stent experimental set-up, with latex tubing simulating flexible ureters attached to vessels simulating renal units and bladders. The flow behavior of five ureteral stents-polymeric 8F, tandem 6F, tandem 7F, endopyelotomy and metal-was tested under a ureteral deformation configuration of 40°, with 2000 g external force over a 3.5 cm length of the ureter. A constant fluid flow was applied through the ureter-stent configurations, and pressure fluctuations in the renal unit were monitored. We considered a renal unit pressure of 10 cmH 2 O or flow discontinuation in the bladder as stent failure. Urine containing debris was mimicked by use of a colloidal solution., Results: Of all assessed ureteral stents, under EUO conditions, only the single 8F stents remained patent throughout the length of the experiment. All other stents-tandem 6F and 7F, single 7F, metal and endopyelotomy-displayed limitations., Conclusions: Tandem and metal stents show no superiority over large luminal polymeric stents for EUO treatment in this in vitro model. Larger luminal stents offer excellent resistance to external pressure and allow adequate colloidal flow. The need for frequent exchange and bladder irritation should also be considered in the choice of stent configuration for treatment of kidney drainage under EUO., (© 2021. The Author(s).)

Background: Urologic guidelines recommend perioperative instillation of chemotherapy after transurethral resection of bladder tumor (TURBT) to decrease tumor recurrence, yet implementation of this recommendation is partial due to associated morbidity. Hypertonic saline destroys cells by osmotic dehydration and might present a safer alternative., Objective: To evaluate the safety of 3% hypertonic saline (Hypersal) intravesical instillation following TURBT in rats and in humans., Methods: In 8 rats whose bladders were electrically injured, intravesical blue-dyed Hypersal was administered. We measured serum sodium levels before and after instillation and pathologically evaluated their pelvic cavity for signs of inflammation or blue discoloration. Twenty-four patients were recruited to the human trial (NIH-NCT04147182), 15 comprised the interventional and 10 the control group (one patient crossed over). Hypersal was given postoperatively. Serum sodium was measured before, 1 hour and 12-24 hours after instillation. Adverse effects were documented and compared between the groups., Results: In rats, average sodium levels were 140.0 mEq/L and 140.3 mEq/L before and following instillation, respectively. Necropsy revealed no signs of inflammation or blue discoloration. In humans the average plasma sodium levels were 138.6 mEq∖L, 138.8 mEq∖L and 137.7 mEq∖L before, 1 hour and 12-24 hours after instillation, respectively. During the postoperative follow-up there was one case of fever. A month after the surgery, dysuria was reported by 5 patients while urgency and hematuria were reported by one patient each. The most severe adverse events were grade 2 on the Clavien-Dindo scale. Adverse events were similar in the control group., Conclusions: Hypersal instillation is safe and tolerable immediately after TURBT., Competing Interests: Jonathan Modai, Alexey Kovalyonok, Avigdor Scherz, Dina Preise, Yuval Avda, Igal Shpunt, Keren Sasson, Morad Jaber, Yamit Peretz, Roy Croock, Yaniv Shilo, Sergey Ikher, Uri Lindner and Dan Leibovici have no conflict of interest to report., (© 2021 – IOS Press. All rights reserved.)

Background: Calcium oxalate (CaOx) stones are considered to be highly resistant to chemolysis. While significant organic matter has been identified within these stones, which is presumed to bind (inorganic) CaOx particles and aggregates, most chemolysis efforts have focused on methods to attack the CaOx components of a stone. We examine the feasibility of inducing chemolysis of CaOx kidney stones, within hours, by specifically attacking the organic matrix present in these stones., Methods: In contrast to previous studies, we focused on the possible "brick and mortar" stone configuration. We systematically tested, via in vitro experiments, the ability of an extensive range of 26 potential chemolysis agents to induce relatively fast disintegration (and/or dissolution) of a large set of natural CaOx stone fragments, extracted during endourological procedures, without regard to immediate clinical application. Each stone fragment was monitored for reduction in weight and other changes over 72 h., Results: We find that agents known to attack organic material have little, if any, effect on stone chemolysis. Similarly, protein and enzymatic agents, and oral additive medical treatments, have little immediate effect., Conclusions: These findings suggest that the organic and inorganic constituents present in CaOx stones are not structured as "brick and mortar" configurations in terms of inorganic and organic components.

INTRODUCTION Distal ureteral stones (DUS) are common in patients presenting to the emergency department (ED) with renal colic. The majority of DUS will pass spontaneously and therefore conservative care is common. Follow up is imperative as some of these stones might not pass and potentially lead to complications. The aim of our study was to evaluate the rate of compliance with follow up and to find predictive variables for it., Materials and Methods: We retrospectively surveyed the medical records of all patients who had a non-contrast computed tomography (NCCT) at our ED between 01/03/16 and 31/5/17. We included patients with a DUS smaller than 10 mm that were treated conservatively. We obtained demographic, clinical, laboratory and imaging data. Compliance to follow up was evaluated by surveying the medical records and by calling the patients. We then compared the characteristics of patients who returned for follow up to those who did not., Results: A total of 230 consecutive patients were included in our cohort: 194 (84%) patients were male and the average age was 46 y (21-82); 138 patients (60%) returned for a follow up visit while 92 patients (40%) did not. Univariate analysis revealed stone size and admission to hospital to be predictive of compliance to follow up while multivariate analysis revealed only hospital admission to be predictive of compliance., Conclusions: Only 60% of the patients with DUS treated conservatively return for a follow up visit. Hospital admission, which likely reflects appropriate patients counseling by a urologist and adequate follow up scheduling, was found to be associated with increased compliance with follow up.

Background and Purpose: Drainage of an obstructed kidney due to extrinsic ureteral obstruction (EUO) is imperative. Ureteral stents, commonly employed to facilitate drainage, often fail under EUO; this is usually attributed to external pressure over the ureter that occludes the stent lumen. We showed previously that external pressure and deformation of the ureter, alone, cannot explain frequent stent failure and speculated that colloids present in urine may play a critical synergetic role. In this study, we evaluate the role of colloidal fluid in ureteral obstruction under extrinsic compression. Materials and Methods: An in vitro ureter-stent model was employed using a latex tube to simulate a flexible ureter connecting simulated glass kidney and bladder units. The ureter was placed in deformed configuration of 40° with external pressure of 2000 g exerted over the deformed region of the stented ureter, representing extrinsic pressure. Four different ureteral stents were tested-4.8F, 6F, 7F, and 8F. Colloidal solution based on chicken albumin was injected through the simulated kidney into the stented ureter. Four replicates were performed for each stent diameter and straight stented ureters with no external pressure were used as controls. Stent failure was defined as kidney unit pressure over 10 cmH 2 O or complete obstruction of fluid flow; time to stent failure was measured. Results: Average failure time in 4.8F and 6F stents was 44 and 66 hours, respectively. The 7F ureteral stent failed in two replicates, after an average time of 75 hours, and continued to drain in the other two replicates. The 8F and control stents showed no change in kidney unit pressure in any of the replicates. Conclusions: Large-diameter stents are more effective in ureteral drainage under EUO in the presence of colloidal material in the fluid. Colloidal fluid may have a role in stent failure under EUO.

Background and Purpose: Extrinsic ureteral obstruction is caused frequently by pelvic malignancies or metastatic lymphadenopathy, necessitating renal drainage with ureteral stents to prevent renal failure and kidney damage. Understanding the nature of stent behavior under deformation and realistic external pressures may assist in evaluation of stent performance. Few published studies have investigated the flow and mechanical properties of stents within ureters, and none has considered the effects of deformation and compression on flow in realistic, in vitro , ureter-stent systems. The purpose of this work was to determine whether or not stent failure is due only to stent compression and deformation in the presence of extrinsic obstruction. Methods: We developed an in vitro ureter-stent experimental setup, using latex tubing to simulate a flexible ureter connecting a renal unit and a bladder side. We examined flow behavior in three stents (4.8F, 6F, 7F). The ureter-stent configuration was varied, simulating four levels of deformation (0°, 20°, 40°, 60°) and then simulating different external compressive forces on a stented ureter with 40° deformation. A constant, realistic fluid flow was applied through the ureter-stent configurations, and pressure fluctuations in the renal unit were monitored. Results: Deformation alone on four different levels (0°, 20°, 40°, 60°) has essentially no influence on fluid flow and renal pressure variation. Under increasing external compressive forces of 500, 1000, 2000, and up to 5000 g at 40° deformation, no effect on fluid flow and pressure within the renal unit was noted for the 6F and 7F stents. The only exception was for the 4.8F stent, which demonstrated complete failure at compressive forces near 4000 g. Conclusions: Neither realistic extrinsic ureteral compression forces nor ureteral deformation explain the high frequency of stent failure in extrinsic ureteral obstruction. Other factors such as urine composition may be a major contributor to stent failure.

Introduction and Objective: Eighty percent of patients with distal ureteral stones <10 mm will ultimately pass the stone under conservative care. Nonetheless, some may experience related morbidity before surgical intervention is performed. Our study aims to find predictive variables for surgical intervention. Methods: We retrospectively surveyed medical records of patients found to have distal ureteral stone up to 10 mm by noncontrast computed tomography (NCCT) done between March 1, 2016 and May 31, 2017. Demographic, clinical, laboratory, and radiologic data were obtained. We compared characteristics of patients who underwent surgical intervention (ureteroscopy/renal drainage) with those treated conservatively. Results: A total of 268 consecutive patients were included: 226 (84%) were male and the average age was 46 years (18-82). Of these patients, 60 patients (22%) underwent surgical intervention (group 1) and 208 patients (78%) were treated expectantly (group 2). No significant differences were observed with respect to demographic data or proportion of patients treated with medical expulsive therapy between the groups. Univariate analysis found stone diameter, stone-to-ureterovesical junction (UVJ) distance, stone density, presence of a "rim sign" on NCCT, and pain duration at presentation to be significantly different between the groups. Multivariate analysis showed stone diameter, stone-to-UVJ distance, and pain duration at presentation to be independently predictive for intervention. Receiver operating characteristics curve analysis identified stone size >4 mm, stone-to-UVJ distance >4 mm, and pain duration >4 days to be the most significant cutoff points for patient risk stratification-"Rule of 4's." Further analysis showed that the prevalence of intervention among patients with 0, 1, 2, and 3 risk factors was 4.3%, 22.1%, 45%, and 66.7%, respectively. Conclusions: Stone size, stone distance from the UVJ, and pain duration play a significant role in predicting surgical intervention. "Rule of 4's" may aid in early recognition of patients who will ultimately undergo intervention and omit the burden of nonfavorable expectant management.

The possible phases and the nanoscale particle correlations of two-dimensional interacting dipolar particles is a long-sought problem in many-body physics. Here we observe a spontaneous condensation of trapped two-dimensional dipolar excitons with internal spin degrees of freedom from an interacting gas into a high density, closely packed liquid state made mostly of dark dipoles. Another phase transition, into a bright, highly repulsive plasma, is observed at even higher excitation powers. The dark liquid state is formed below a critical temperature Tc ≈ 4.8 K, and it is manifested by a clear spontaneous spatial condensation to a smaller and denser cloud, suggesting an attractive part to the interaction which goes beyond the purely repulsive dipole-dipole forces. Contributions from quantum mechanical fluctuations are expected to be significant in this strongly correlated, long living dark liquid. This is a new example of a two-dimensional atomic-like interacting dipolar liquid, but where the coupling of light to its internal spin degrees of freedom plays a crucial role in the dynamical formation and the nature of resulting condensed dark ground state.

Purpose: The robot-assisted approach to distal ureteral reconstruction is increasingly utilized. Traditionally, the robot is docked between the legs in lithotomy position resulting in limited bladder access for stent placement. We examined the use of side docking of the daVinci robot® to perform distal ureteral reconstruction., Materials and Methods: A retrospective review of distal ureteral reconstruction (ureteral reimplantation and uretero-ureterostomy) executed robotically was performed at a single institution by a single surgeon. The daVinci robotic® Si surgical platform was positioned at the right side of the patient facing towards the head of the patient, i.e. side docking., Results: A total of 14 cases were identified from 2011-2013. Nine patients underwent ureteral reimplantation for ureteral injury, two for vesicoureteral reflux, one for ureteral stricture, and one for megaureter. One patient had an uretero-ureterostomy for a distal stricture. Three patients required a Boari flap due to extensive ureteral injury. Mean operative time was 286 minutes (189-364), mean estimated blood loss was 40cc (10-200), and mean length of stay was 2.3 days (1-4). Follow-up renal ultrasound was available for review in 10/14 patients and revealed no long-term complications in any patient. Mean follow-up was 20.7 months (0.1-59.3)., Conclusion: Robot-assisted laparoscopic distal ureteral reconstruction is safe and effective. Side docking of the robot allows ready access to the perineum and acceptable placement of the robot to successfully complete ureteral repair.

Background and Purpose: Ureteral injuries such as avulsion are directly related to mechanical damage of the ureter. Understanding the tensile strength of this tissue may assist in prevention of iatrogenic injuries. Few published studies have looked at the mechanical properties of the animal ureter and, of those, none has determined the tensile strength of the human ureter. Therefore, the purpose of this work was to determine the tensile strength of the human ureter., Methods: We harvested 11 human proximal ureters from patients who were undergoing nephrectomy for either kidney tumors or nonfunctioning kidney. The specimens were then cut into multiple circumferentially and longitudinally oriented tissue strips for tensile testing. Strips were uniaxially stretched to failure in a tensile testing machine. The corresponding force and displacement were recorded. Finally, stress at failure was noted as the tensile strength of the sample. Circumferential tensile strength was also compared in the proximal and distal regions of the specimens., Results: The tensile strength of the ureter in circumferential and longitudinal orientations was found to be 457.52±33.74 Ncm(-2) and 902.43±122.08 Ncm(-2), respectively (P<0.001). The circumferential strength in the proximal portion of the ureter was 409.89±35.13 Ncm(-2) in comparison with 502.89±55.85 Ncm(-2) in the distal portion (P=0.08)., Conclusions: The circumferential tensile strength of the ureter was found to be significantly lower than the longitudinal strength. Circumferential tensile strength was also lower with more proximal parts of the ureter. This information may be important for the design of "intelligent" devices and simulators to prevent complications.

Objective: To assess the efficacy of dietary management for the treatment of idiopathic hyperoxaluria in a large tertiary care center and examine the influence of patient factors, compliance, and follow-up on oxalate reduction, which has not been previously investigated., Methods: Retrospectively, 149 patients with kidney stones with idiopathic hyperoxaluria who received dietary management at our stone clinic were evaluated. Changes in urinary parameters on 24-hour urine collections were calculated for all patients and those with abnormal values in the overall short-term (30-240 days) and long-term (>240 days) time periods. Changes in urinary oxalate were evaluated with respect to patient characteristics and compliance measures., Results: Urine oxalate and supersaturation of calcium oxalate were significantly (P < .001) reduced by 8.9 ± 19.2 mg/d and 1.7 ± 4.3, respectively. A total of 48.3% of the patients reduced their urinary oxalate to normal. Urine oxalate reductions were similar in the short-term and long-term periods. Women lowered urine oxalate nearly twice as much as men (12.7 ± 2.0 mg/d vs 6.7 ± 2.2 mg/d, P = .022) and body mass index (BMI) negatively correlated with oxalate reduction (Pearson's r = -0.213). Reported noncompliance and keeping follow-up appointments did not affect oxalate, however, there was a significant correlation between increasing urine volume and reducing oxalate (Pearson's r = -0.21)., Conclusion: This study confirms that meaningful reductions of urine oxalate and supersaturation of calcium oxalate can be achieved with dietary management of hyperoxaluria on a larger clinical scale. Furthermore, we identified that women and patients with low BMIs had greater urine oxalate reductions and urine volume may also be used by clinicians as a measure of dietary compliance., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Objectives: To determine the effect of prostate volume on the diagnostic yield of prostate biopsies., Materials and Methods: 155 consecutive patients underwent 12-core transrectal ultrasound guided needle biopsies. Data were collected prospectively on age, serum PSA, digital rectal examination (DRE), previous prostate biopsies, prostate volume and pathologic result. Univariate and multivariate logistic regressions were undertaken to determine the effect of prostate volume on the risk for a positive biopsy., Results: 45 patients (29%) were diagnosed with cancer. The median patient age was 63 (range 48-82) years, the median PSA level was 6.7 ng/ml (0.5-156 ng/ml), and the median prostate volume was 57 ml (16-273 ml). 42 patients (27%) had an abnormal DRE and 51 (33%) had undergone previous prostate biopsies. Positive biopsy rates were 39%, 33%, and 14% for prostate volume below 46 ml, between 45 and 73 ml, and above 72 ml, respectively. Univariate analysis showed that age, serum PSA, DRE and prostate volume were all associated with a positive biopsy. Multivariate analysis adjusted for age, PSA and DRE showed a significant risk increase for a positive biopsy in smaller prostates. (OR = 5.6 95% CI 1.75-17.89; and 8.86 95% CI 2.72-28.82, for prostate volume between 45 and 72 ml and below 45 ml, respectively)., Conclusion: The diagnostic yield of prostate biopsies is significantly lower in large prostates. As the result the standard 12-core biopsy may be insufficient for the diagnosis of cancer in large prostates., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Background: Recommendations for active surveillance versus immediate treatment for low risk prostate cancer are based on biopsy and clinical data, assuming that a low volume of well-differentiated carcinoma will be associated with a low progression risk. However, the accuracy of clinical prediction of minimal prostate cancer (MPC) is unclear., Objectives: To define preoperative predictors for MPC in prostatectomy specimens and to examine the accuracy of such prediction., Methods: Data collected on 1526 consecutive radical prostatectomy patients operated in a single center between 2003 and 2008 included: age, body mass index, preoperative prostate-specific antigen level, biopsy Gleason score, clinical stage, percentage of positive biopsy cores, and maximal core length (MCL) involvement. MPC was defined as < 5% of prostate volume involvement with organ-confined Gleason score < or = 6. Univariate and multivariate logistic regression analyses were used to define independent predictors of minimal disease. Classification and Regression Tree (CART) analysis was used to define cutoff values for the predictors and measure the accuracy of prediction., Results: MPC was found in 241 patients (15.8%). Clinical stage, biopsy Gleason's score, percent of positive biopsy cores, and maximal involved core length were associated with minimal disease (OR 0.42, 0.1, 0.92, and 0.9, respectively). Independent predictors of MPC included: biopsy Gleason score, percent of positive cores and MCL (OR 0.21, 095 and 0.95, respectively). CART showed that when the MCL exceeded 11.5%, the likelihood of MPC was 3.8%. Conversely, when applying the most favorable preoperative conditions (Gleason < or = 6, < 20% positive cores, MCL < or = 11.5%) the chance of minimal disease was 41%., Conclusions: Biopsy Gleason score, the percent of positive cores and MCL are independently associated with MPC. While preoperative prediction of significant prostate cancer was accurate, clinical prediction of MPC was incorrect 59% of the time. Caution is necessary when implementing clinical data as selection criteria for active surveillance.

Purpose: We compared symptoms in women with detrusor overactivity with impaired contractility and women with detrusor overactivity who had preserved contractility., Materials and Methods: The study included 359 consecutive women with detrusor overactivity who underwent multichannel urodynamics at our department between 2009 and 2011. The women were divided into 2 groups, including 151 (42%) with detrusor overactivity and impaired contractility, and 208 (58%) with detrusor overactivity and preserved contractility. We compared the 2 groups., Results: Women with detrusor overactivity and impaired contractility were older (mean ± SD age 73.2 ± 17.3 vs 54.1 ± 20.7 years) with a higher frequency of diabetes mellitus (49% vs 31%, each p <0.001). The prevalence of previous urinary retention and recurrent cystitis was significantly higher in women with impaired contractility (7% vs 1%, p <0.01 and 22% vs 7%, p <0.001, respectively). Mean post-void residual urine was greater in the group with impaired contractility (89 ± 42 vs 21 ± 18 ml) and the mean maximal flow rate was lower (11 ± 6 vs 23 ± 5 ml per second, each p <0.001). The frequency of storage symptoms was similar in the 2 groups. However, voiding symptoms were more common in women with impaired contractility, including a slow stream in 69% vs 42%, an intermittent stream in 72% vs 26%, hesitancy in 35% vs 22%, straining in 84% vs 26%, terminal dribbling in 73% vs 42% and incomplete emptying in 71% vs 49% (p <0.001)., Conclusions: Women with detrusor overactivity and impaired contractility are older than women with detrusor overactivity and preserved detrusor contractility. Urinary retention and recurrent cystitis are more frequent in women with detrusor overactivity and impaired contractility, and voiding symptoms are significantly more common., (Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.)

Background: Hemorrhagic radiation cystitis (HRC) is a significant clinical problem that occurs after pelvic radiation therapy and is often refractory., Objectives: To evaluate the efficacy and safety of hyperbaric oxygen therapy (HBO) for HRC., Methods: Daily 90 minute sessions of HBO at 2 ATM 100% oxygen were given to 32 HRC patients with ASTRO grades 3-4 hematuria., Results: The median age was 72.5 (48-88 years). The median time interval between radiation therapy and HBO was 4 years (1-26 years). The patients received a median of 30 HBO sessions (3-53). Hematuria resolved in 27 patients (84%) and persisted in 5. Cystectomy was required in two, and ileal-conduit and bilateral percutaneous nephrostomies were performed in one and two patients, respectively. With a median follow-up of 12 months (5-74 months), the hematuria cleared completely in 16 patients (59%) and mild hematuria requiring no further treatment recurred in 10 others. Another patient with ASTRO grade 4 hematuria needed bladder irrigation and blood transfusions. Complications included eardrum perforation in four patients and transient vertigo and mild hemoptysis in one case each. None of them required HBO discontinuation., Conclusions: HBO controlled bleeding in 84% of the patients. A durable freedom from significant hematuria was achieved in 96% of the patients. HBO seems to be an effective and safe modality in patients with HRC.

Dipolar excitons are long-lived quasi-particle excitations in semiconductor heterostructure that carry an electric dipole. Cold dipolar excitons are expected to have new quantum and classical multi-particle correlation regimes, as well as several collective phases, resulting from the intricate interplay between the many-body interactions and their quantum nature. Here we show experimental evidence of a few correlation regimes of a cold dipolar exciton fluid, created optically in a semiconductor bilayer heterostructure. In the higher temperature regime, the average interaction energy between the particles shows a surprising temperature dependence, which is evidence for correlations beyond the mean field model. At a lower temperature, there is a sharp increase in the interaction energy of optically active excitons, accompanied by a strong reduction in their apparent population. This is evidence for a sharp macroscopic transition to a dark state, as has been suggested theoretically.

Objectives: To evaluate the concordance between testicular tumor size and benign histology in order to identify a cut-off size, below which the rate of benign lesions would be highest., Methods and Materials: During the years 1995-2008, we performed 131 consecutive testicular operations for testicular tumors. Ten of these were testicular preserving surgery, whereas the other 121 patients had radical orchiectomy. We searched for the rate of benign lesions in the following 3 groups of tumor diameter: 10 mm or less, 11-20 mm, and greater than 20 mm. ROC analysis was used to find the optimal size cut-off below which the rate of benign lesions would be highest., Results: Benign lesions were found in 11 patients (8%), including epidermoid cyst (n = 4), Leydig cell tumor (n = 3), fibrosis (n = 1), adenomatoid tumor (n = 2), and 1 patient with a simple cyst. Small tumor size strongly correlated with benign histology. The mean diameter of benign vs. malignant lesions was 15 mm and 41 mm, respectively (P < 0.05). The rate of benign lesions in tumors with a diameter of 10 mm or less, 11-20 mm and greater than 20 mm was 50%, 17%, and 2%, respectively. Receiver Operating characteristic (ROC) analysis with 87% sensitivity and 83% specificity revealed a cut-off value of 18.5 mm tumor diameter below which the proportion of benign lesions was 38.5% compared with 2% above it (P < 0.05)., Conclusions: While benign lesions comprise only 8% of all testicular tumors, their proportion among small lesions is much higher. With a size cut-off of 18.5 mm, 38.5% of smaller lesions are benign. These findings support consideration of testicular exploration for small testicular lesions aiming at preservation rather than predetermined radical orchiectomy., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Unlabelled: HISTORY AND PRESENTATION: A 12 year old, 4.2 kg, domestic long hair, castrated male cat was presented with regurgitation, inability to retract the claws, general weakness, cervical ventroflexion and weight loss. A thymic mass was evident on radiographs. Acetylcholine receptor antibody titer was positive for acquired myasthenia gravis (MG). Thymectomy via midline sternotomy was scheduled. ANESTHETIC MANAGEMENT:  Oxymorphone and atropine were administered subcutaneously as premedication, and anesthesia was induced with etomidate and diazepam given intravenously to effect. The cat's trachea was intubated and anesthesia was maintained with isoflurane in oxygen, and continuous infusions of remifentanil and ketamine. Epidural analgesia with preservative-free morphine was administered prior to surgery. Postoperative analgesia was provided by oxymorphone subcutaneously, interpleural bupivacaine, and fentanyl infusion. Postoperative complications included airway obstruction, hypoxemia and hypercapnia., Follow-Up: The cat was discharged 3 days after surgery. Discharge medications included pyridostigmine and prednisone. Nine days after surgery, the cat had a significant increase in its activity level, and medications were discontinued. Histopathologically, the mass was consistent with a thymoma. Approximately 6 weeks later the cat became weak again and pyridostigmine and prednisone administration was resumed., Conclusion: The perioperative management of patients with MG for transsternal thymectomy is a complex task. The increased potential for respiratory compromise requires the anesthesiologist to be familiar with the underlying disease state, and the interaction of anesthetic and non-anesthetic drugs with MG. Careful monitoring of ventilation and oxygenation is indicated postoperatively., (© 2011 The Authors. Veterinary Anaesthesia and Analgesia. © 2011 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists.)