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Roughly 10% of the world’s population has chronic kidney disease (CKD). In its advanced stages, CKD greatly increases the risk of hospitalization and death. Although kidney transplantation has revolutionized the care of advanced CKD, clinicians have limited ways of assessing donor kidney quality. Thus, optimal donor kidney–recipient matching cannot be performed, meaning that some patients receive damaged kidneys that function poorly. Fibrosis is a form of chronic damage often present in donor kidneys, and it is an important predictor of future renal function. Currently, no safe, easy-to-perform technique exists that accurately quantifies renal fibrosis. We describe a potentially novel photoacoustic (PA) imaging technique that directly images collagen, the principal component of fibrotic tissue. PA imaging noninvasively quantifies whole kidney fibrotic burden in mice, and cortical fibrosis in pig and human kidneys, with outstanding accuracy and speed. Remarkably, 3-dimensional PA imaging exhibited sufficiently high resolution to capture intrarenal variations in collagen content. We further show that PA imaging can be performed in a setting that mimics human kidney transplantation, suggesting the potential for rapid clinical translation. Taken together, our data suggest that PA collagen imaging is a major advance in fibrosis quantification that could have widespread preclinical and clinical impact.

Objective To review our experience using clips to control the renal vessels during laparoscopic donor nephrectomy (LDN) and determine the safety of this practice. Methods We performed a retrospective review of patients who underwent LDN at our centre January 1, 2007-September 17, 2019. The primary outcome was the rate of complication associated with vascular control of the renal vessels, which included (1) conversion to open to manage bleeding, (2) additional procedures for bleeding, and (3) major bleeding requiring blood transfusion. Secondary outcomes included the rate of renal artery/vein clip dislodgement or crossing, change in hemoglobin, warm ischemia time and the incidence of intra-operative complications and postoperative in-hospital complications. Results We included 503 patients who underwent LDN, of which 497 were left sided. The main renal artery was controlled with 3 titanium clips in 489 (97%) cases. The main renal vein was controlled with 2 polymer-locking clips in 478 (95%) cases. For our primary outcome, there were no conversions to open to manage bleeding, no secondary procedures due to bleeding and no major bleeding requiring blood transfusion. Additionally, there were no donor deaths. Regarding our secondary outcomes, there were 5 intraoperative events related to the titanium clips being placed on the renal artery and 1 intraoperative event related to the polymer-locking clips on the renal vein, none of which resulted in any morbidity. Conclusion Using 3 titanium clips on the renal artery and 2 polymer-locking clips on the renal vein during left LDN is safe and provides excellent vascular control.

Introduction: Routine crossmatch of packed red blood cells (pRBCs) is completed preoperatively at many centers despite conflicting evidence on the incidence of blood transfusions with renal transplantation. In the current economic climate, resource adjudication should be judicious and medically appropriate. The objective of this study was to determine the incidence, timing, and predictors of early postoperative pRBC transfusion in patients undergoing renal transplantation. Methods: A retrospective review of all patients undergoing renal transplantation at our institution from January 2013 to May 2016 was performed. Demographic, biochemical, and clinical parameters were recorded. The primary outcome was early postoperative transfusion, defined as an intraoperative transfusion or within 2 days of surgery. Multivariable logistic regression was performed to identify associations with early postoperative transfusion. Results: We identified 428 patients during the study period (average age 55 years, 60% male, 30% obese, 67% deceased donor, and 43% preoperative antithrombotic use). Forty (9.3%) patients required early postoperative transfusion (mean: 2.8 pRBCs/transfusion) and most did not require blood urgently. Only 20 (4.7%) patients required a transfusion intraoperatively or on the same day of surgery. Lower preoperative hemoglobin (per g/L unit: odds ratio [OR]: 0.943), female gender (OR: 2.752), and preoperative antithrombotic use (OR 2.369) were associated with a need for early postoperative transfusion. Conclusion: Transfusion in the early postoperative period following renal transplantation was less than 10%, suggesting that routine crossmatch may not be necessary for all patients. Preoperative hemoglobin, female gender, and preoperative antithrombotic use were associated with increased risk and may be useful to risk-stratify patients who require crossmatch.

OBJECTIVE To determine how effective routine postoperative blood work is in identifying complications after percutaneous nephrolithotomy (PCNL), the gold standard treatment for large volume stone disease. Although major complication rates are low, hemorrhagic and sepsis-related complications are serious and can occur. Routine post-PCNL complete blood count is routinely performed by most endourologists but may be a low-value practice. METHODS A retrospective review was performed of all PCNL procedures at our center over a 3-year period. Patient demographic, stone characteristics and postoperative data were collected and analyzed. RESULTS Three hundred and eighty-five patients (196 female and 189 males) underwent PCNL for the treatment of urolithiasis. Mean age was 55.8 years and mean length of stay in hospital was 1.74 days. Most patients (82.9%) had neither ureteric stent nor percutaneous tube prior to PCNL. Postoperatively, 4 patients (1.0%) required a blood transfusion and 14 patients (3.6%) developed urosepsis. Patients who required either a transfusion or developed urosepsis demonstrated abnormal vital signs (tachycardia, hypotension, or fever) postoperatively. Sixteen patients (4.2%) had normal vital signs but had an extended hospital stay only to monitor abnormal blood work results. None these patients required a transfusion nor developed urosepsis but had a length of stay that was a mean of 1.5 days longer patients with normal postoperative vital signs and blood work. CONCLUSION Abnormal vital signs alone identified all patients that required transfusion or treatment for urosepsis after PCNL. Routine complete blood count testing postoperatively may not improve detection of infectious or bleeding complications and may prolong hospital admission unnecessarily.

Introduction: Preoperative alpha-blockers have been proposed to improve intraoperative outcomes and patient stone-free status after ureteroscopy for ureteral stones. Materials and Methods: We searc...

Routine preoperative electrocardiogram (ECG) before shockwave lithotripsy (SWL) is frequently performed despite recommendations against its use in asymptomatic patients undergoing low-risk surgical procedures. This study assesses whether routine preoperative ECG before SWL is useful in patients at low risk for cardiac complications.A retrospective study of SWL at our center (2003-2013) reviewed all cardiac-related preoperative cancellations, intraoperative complications, postoperative admissions, and emergency department presentations in patients at low risk for cardiac complications. Patients received SWL with sedation and continuous five-lead ECG monitoring.Of 30,892 referrals, preoperative ECG triggered 13 (0.04%) cancelations in low-risk patients (1 with new atrial fibrillation and 12 with ischemia/previous infarction). Of these patients, 1 had a subsequent abnormal cardiac work-up and 11 underwent uncomplicated SWL without cardiac intervention (2 had unknown history). Of 27,722 treatments, 5 (0.02%) were stopped prematurely in low-risk patients because of arrhythmia (3 had normal preoperative ECG, 1 had abnormal ECG, and 1 did not complete ECG). Three patients developed an arrhythmia with sedation and 2 patients were admitted postoperatively because of cardiac complications (1 for atrial fibrillation and 1 for hypertension), of whom all had normal preoperative ECG. No patients presented to our emergency department with cardiac complications after SWL.In patients at low risk for cardiac complications, preoperative ECG triggered very few cancellations and did not predict early termination of treatment or cardiac complications after SWL. These findings suggest that in low-risk patients, routine preoperative ECG has little effect on treatment or complication rate and should be omitted.

BACKGROUND Shock wave lithotripsy (SWL), ureteroscopy, and percutaneous nephrolithotomy are established treatments for renal stones. Historically, SWL has been a predominant and commonly used procedure for treating upper tract renal stones smaller than 20 mm in diameter due to its noninvasive nature. However, the reported failure rate of SWL after one treatment session ranges from 30% to 89%. The failure rate can be reduced by identifying candidates likely to benefit from SWL and manage patients who are likely to fail SWL with other treatment modalities. This would enhance and optimize treatment results for SWL candidates. OBJECTIVE We proposed to develop a machine learning model that can predict SWL outcomes to assist practitioners in the decision-making process when considering patients for stone treatment. METHODS A data set including 58,349 SWL procedures performed during 31,569 patient visits for SWL to a single hospital between 1990 and 2016 was used to construct and validate the predictive model. The AdaBoost algorithm was applied to a data set with 17 predictive attributes related to patient demographics and stone characteristics, with success or failure as an outcome. The AdaBoost algorithm was also applied to a training data set. The generated model’s performance was compared to that of 5 other machine learning algorithms, namely C4.5 decision tree, naïve Bayes, Bayesian network, K-nearest neighbors, and multilayer perceptron. RESULTS The developed model was validated with a testing data set and performed significantly better than the models generated by the other 5 predictive algorithms. The sensitivity and specificity of the model were 0.875 and 0.653, respectively, while its positive predictive value was 0.7159 and negative predictive value was 0.839. The C-statistics of the receiver operating characteristic (ROC) analysis was 0.843, which reflects an excellent test. CONCLUSIONS We have developed a rigorous machine learning model to assist physicians and decision-makers to choose patients with renal stones who are most likely to have successful SWL treatment based on their demographics and stone characteristics. The proposed machine learning model can assist physicians and decision-makers in planning for SWL treatment and allow for more effective use of limited health care resources and improve patient prognoses.

Background Shock wave lithotripsy (SWL), ureteroscopy, and percutaneous nephrolithotomy are established treatments for renal stones. Historically, SWL has been a predominant and commonly used procedure for treating upper tract renal stones smaller than 20 mm in diameter due to its noninvasive nature. However, the reported failure rate of SWL after one treatment session ranges from 30% to 89%. The failure rate can be reduced by identifying candidates likely to benefit from SWL and manage patients who are likely to fail SWL with other treatment modalities. This would enhance and optimize treatment results for SWL candidates. Objective We proposed to develop a machine learning model that can predict SWL outcomes to assist practitioners in the decision-making process when considering patients for stone treatment. Methods A data set including 58,349 SWL procedures performed during 31,569 patient visits for SWL to a single hospital between 1990 and 2016 was used to construct and validate the predictive model. The AdaBoost algorithm was applied to a data set with 17 predictive attributes related to patient demographics and stone characteristics, with success or failure as an outcome. The AdaBoost algorithm was also applied to a training data set. The generated model’s performance was compared to that of 5 other machine learning algorithms, namely C4.5 decision tree, naïve Bayes, Bayesian network, K-nearest neighbors, and multilayer perceptron. Results The developed model was validated with a testing data set and performed significantly better than the models generated by the other 5 predictive algorithms. The sensitivity and specificity of the model were 0.875 and 0.653, respectively, while its positive predictive value was 0.7159 and negative predictive value was 0.839. The C-statistics of the receiver operating characteristic (ROC) analysis was 0.843, which reflects an excellent test. Conclusions We have developed a rigorous machine learning model to assist physicians and decision-makers to choose patients with renal stones who are most likely to have successful SWL treatment based on their demographics and stone characteristics. The proposed machine learning model can assist physicians and decision-makers in planning for SWL treatment and allow for more effective use of limited health care resources and improve patient prognoses.

OBJECTIVE To determine if patients treated with extracorporeal shockwave lithotripsy (ESWL) are at a greater risk of developing diabetes mellitus (DM) than those treated with ureteroscopy (URS). PATIENTS AND METHODS A retrospective population-based cohort study was performed of all ESWL and URS stone treatments done in Ontario between January 1994 and March 2014, utilising linked encoded healthcare databases. The primary outcome was the development of DM >90 days after treatment. The Kaplan-Meier method was used for unadjusted survival analysis and multivariable analysis with Cox proportional hazards regression was used to assess the risk of DM between the ESWL and URS groups whilst controlling for age, gender, region of residence, income quintile, year of treatment, and comorbidity index. A sensitivity analysis with a subset of ESWL patients treated for left renal or proximal ureteric stones was completed. RESULTS We identified 106 963 patients who underwent ESWL or URS over the study period with a median follow-up of 6.6 years (ESWL 8.5 years, URS 5.6 years). Unadjusted survival analysis showed an increased risk of developing DM in the ESWL group compared to the URS group (P

Iatrogenic ureteral injuries account for ∼75% of all ureteral injuries and occur primarily during urologic, gynecologic, general, and vascular surgery procedures. Ureteral injury during spine surgery is a rare complication with only occasional reports in the literature. In this case report, we present a case of unrecognized left ureteral injury during an open right lumbar discectomy with a delayed presentation, and discuss the steps required for diagnosis and management. This report highlights a rare complication during laminectomy and serves to better inform patients and surgeons about this potential complication and the management options.

Intracorporeal lithotripsy is becoming the most commonly used surgical method of stone treatment in Urology. The five major types of intracorporeal lithotripters are ultrasonic, ballistic, and combination lithotripters as well as laser and electrohydraulic lithotripters. The advantages and disadvantages of choosing each of these treatment modalities are reviewed. Extensive review of literature was performed to identify the types of intracorporeal lithotripters. An investigation was undertaken of the early development of each modality of intracorporeal lithotripsy and/or the mechanism of action. Challenges of each technique were identified and presented. Finally, a determination was made of how these lithotripters compare on the basis of effectiveness of action and cost based on information provided in primary literature as well as previous reviews of these modalities. Contemporary lithotripters have found widespread use in the management of urinary lithiasis. Holmium laser lithotripsy has become one of the most commonly used tools for intracorporeal lithotripsy. There is a wide variety of intracorporeal lithotripters which can be chosen based on the characteristics of each modality and the requirements of the urologist.

As urology training programs move to a competency based medical education model, iterative assessments with objective standards will be required. To develop a valid set of technical skills standards we initiated a national skills assessment study focusing initially on laparoscopic skills.Between February 2014 and March 2016 the basic laparoscopic skill of Canadian urology trainees and attending urologists was assessed using 4 standardized tasks from the AUA (American Urological Association) BLUS (Basic Laparoscopic Urological Surgery) curriculum, including peg transfer, pattern cutting, suturing and knot tying, and vascular clip applying. All performances were video recorded and assessed using 3 methods, including time and error based scoring, expert global rating scores and C-SATS (Crowd-Sourced Assessments of Technical Skill Global Rating Scale), a novel, crowd sourced assessment platform. Different methods of standard setting were used to develop pass-fail cut points.Six attending urologists and 99 trainees completed testing. Reported laparoscopic experience and training level correlated with performance (p 0.01). Attending urologists were significantly better than trainees (p0.05), demonstrating construct validity evidence for the 4 AUA BLUS tasks. The C-SATS method of assessment correlated well with the traditional methods of time and error based scoring, and the global rating scale. We were able to use relative and absolute standard setting methods to define pass-fail cut points for all 4 AUA BLUS tasks.The 4 AUA BLUS tasks demonstrated good construct validity evidence for use in assessing basic laparoscopic skill. Performance scores using the novel C-SATS platform correlated well with traditional time-consuming methods of assessment. Various standard setting methods were used to develop pass-fail cut points for educators to use when making formative and summative assessments of basic laparoscopic skill.

INTRODUCTION: Following the introduction of shock wave lithotripsy (SWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PCNL), the subspecialty of endourology was born in the late 1970s. The purpose of this study was to report milestones in Canadian endourology, highlighting Canada’s contributions to the field. METHODS: A review of the literature was performed from the late 1970s to the present. The literature review included bibliographic and digital resources. Additionally, records and recollections by various individuals were used, including some who were directly involved. RESULTS: Endourology was born in Canada when SWL, URS, and PCNL emerged as minimally invasive treatment options for stones in the early to mid-1980s. According to our research, the first PCNL was performed at the University of Toronto in 1981. Dr. Joachim Burhenne, a Harvard-trained radiologist from Germany, first used extracorporeal SWL in Canada at the University of British Columbia (UBC) for the treatment of biliary stones. Treatment for urinary tract stones followed at UBC and Dalhousie University. The first worldwide use of the holmium laser for lithotripsy of urinary tract calculi took place at the University of Western Ontario. Other endourology milestones in Canada include the formation of the Canadian Endourology Group and the emergence of the Endourological Society-accredited fellowship programs at the University of Toronto and Western University in the 1990s. Canada hosted the 21(st) and 35(th) World Congress of Endourology and Shock Wave Lithotripsy annual meeting in Montreal and Vancouver, respectively. CONCLUSIONS: Canadian urologists have led many advances in SWL, URS, and PCNL over the past four decades and, for a relatively small community, have made significant contributions to the field. Through the training of the next generation of endourologists at Canadian institutions, the future of endourology in Canada is bright.

This Guideline is intended to provide a clinical framework for the surgical management of patients with kidney and/or ureteral stones. The summary presented herein represents Part II of the two-part series dedicated to Surgical Management of Stones: American Urological Association/Endourological Society Guideline. Please refer to Part I for introductory information and a discussion of pre-operative imaging and special cases.A systematic review of the literature (search dates 1/1/1985 to 5/31/2015) was conducted to identify peer-reviewed studies relevant to the surgical management of stones. The review yielded an evidence base of 1,911 articles after application of inclusion/exclusion criteria. These publications were used to create the Guideline statements. Evidence-based statements of Strong, Moderate, or Conditional Recommendation were developed based on benefits and risks/burdens to patients. Additional directives are provided as Clinical Principles and Expert Opinions when insufficient evidence existed.The Panel identified 12 adult Index Patients to represent the most common cases seen in clinical practice. Three additional Index Patients were also created to describe the more commonly encountered special cases, including pediatric and pregnant patients. With these patients in mind, Guideline statements were developed to aid the clinician in identifying optimal management.Proper treatment selection, which is directed by patient- and stone-specific factors, remains the greatest predictor of successful treatment outcomes. This Guideline is intended for use in conjunction with the individual patient's treatment goals. In all cases, patient preferences and personal goals should be considered when choosing a management strategy.

Ureteral stent length is important, as stents that are too long might worsen symptoms and too short are at higher risk of migration. The purpose of this study was to determine if patient or radiologic parameters correlate with directly measured ureteral length and if directly measured ureteral length predicts proper stent positioning.During stent placement, ureteral length (ureteropelvic junction to ureterovesical junction distance) was directly measured by endoscopically viewing a ureteral catheter (with 1-cm marking) emanating from the ureteral orifice. A 22, 24, or 26 cm stent was chosen to be closest to the measured ureteral length. For ureters26 cm, a 26 cm stent was chosen. Ends of an "ideally positioned" stent were fully curled in the renal pelvis and bladder, without crossing the bladder midline. Rates of ideal stent position were compared between patients with matching stent and ureteral lengths and those with stent lengths differing by ≥1 cm (mismatched). The measured ureteral length was correlated with patient height, L1-L5 height, and length measured on CT.Fifty-nine ureters from 57 patients were included. Height was reasonably correlated with L1-L5 height (Spearman correlation coefficient [rho] = 0.79), although both were poorly correlated with directly measured ureteral length (rho = 0.18 for height and 0.32 for lumbar height). Ureteral lengths measured on CT correlated well with direct measurement (rho = 0.63 for axial cuts and rho = 0.64 for coronal cuts). Matched stent length was associated with higher rates of ideal stent position than mismatched (100% vs 70.9%, p = 0.006).CT measurements, rather than height, correlate well with measured length and could be used to choose the appropriate stent length. Stents matching directly measured ureteral lengths are associated with high rates of ideal stent position.

Shockwave lithotripsy (SWL) is a widely utilized form of treatment for urolithiasis. There are new evidence-based recommendations regarding pre-SWL patient work-up and the performance of SWL. The purpose of this study is to determine practice patterns for SWL and to determine if regional variation exists between Canada and the United States.A 19-question survey was prepared. Canadian urologists were surveyed through e-mail correspondence. In the United States, members of the Endourologic Society and members of two large stone management groups were surveyed. Canadian and American results were compared using the chi-square and Fisher's exact tests.Ninety-four Canadian urologists and 187 U.S. urologists completed the survey. Practice patterns differed between countries. Intravenous sedation was more commonly used in Canada (Canada 94.7% vs United States 17.9%, p 0.001); routine antibiotics were more commonly given in United States (Canada 2.1% vs United States 78.1%, p 0.001); a shock rate of 2 Hz was more common in Canada (Canada 76.6% vs United States 16.2%, p 0.00001); rate of discontinuing ASA for renal and ureteral stone treatment was higher in the United States (renal Canada 88.3% vs United States 95.7%, p 0.02; ureteral Canada 62.4% vs 90.3%, p 0.0001); and ureteral stents were more commonly used if treating a large stone or patients with solitary kidneys in the United States (large stones Canada 58.2% vs United States 88.8%, p = 0.0001; solitary kidney Canada 50.6% vs 66.3%, p = 0.02).This study highlights the absence of standardization of SWL. Significant regional differences exist in practice patterns and performance of SWL between Canadian and American urologists.

Robotic surgery is associated with a learning curve unique to each trainee. Knowledge about a trainee's baseline skill and learning curve would facilitate the development of a more individualized training curriculum. The aim of our study was to determine whether baseline laparoscopic skill is predictive of one's baseline robotic skill and short-term learning curve.Trainees from four different surgical specialties were included in the study. Each trainee participated in a 4-week, simulation-based robotic surgery basic skills training course. Precourse, baseline laparoscopic and robotic skills were assessed using validated test tasks; a basic peg transfer (PT) and an advanced intracorporeal suturing and knot tying (ISKT) task. Trainee robotic skill was assessed again 1 week postcourse. Each task performance was video recorded and scored by two blinded expert surgeons.A total of 32 trainees were included; 14 urology, 7 gynecology, 8 thoracic Sx, 3 general Sx. Most (91%) were senior residents or clinical fellows and 50% had no prior robotic experience. There were no differences in baseline laparoscopic and robotic skill related to reported prior robotic experience. Between specialties, no differences were seen on baseline laparoscopic skill and only small differences were seen on baseline robotic skill. Both baseline Lap PT (p = 0.01) and Lap ISKT (p = 0.01) performances correlated with baseline robotic ISKT performance, but not robotic PT scores. Only baseline Lap ISKT performance correlated with postcourse robotic PT (p = 0.01) and ISKT (p 0.01) performance. Baseline robotic ISKT scores, but not PT scores, correlated with postcourse robotic performance (p = 0.02 for PT, p 0.01 for ISKT).In this study, a trainee's baseline laparoscopic skill correlated with certain baseline robotic skills. Better baseline performance on an advanced, but not basic, laparoscopic and robotic skill task may correlate with a shorter learning curve for basic robotic skills. Further exploration of this finding may yield better training curricula.

Introduction: Concurrent peritoneal dialysis (PD) catheter removal during renal transplantation is controversial, with limited evidence supporting this practice. Our objective was to determine the rate of delayed graft function (DGF) in patients on preoperative PD. Additionally, we sought to identify which patients can safely have their PD catheter removed during transplantation due to a low risk of DGF. Methods: We conducted a retrospective observational study between June 2011 and December 2015. The primary outcome was the diagnosis of DGF, defined as the need for dialysis within the first week of transplantation. Clinical and transplant factors, including graft type and donor criteria, were assessed for association with the primary outcome. Catheter-related complication rates were also compared between post-transplant PD and hemodialysis (HD). Results: Of our cohort of 567 patients, 145 patients (25.6%) developed DGF. Obesity (odds ratio [OR] 1.06; 95% confidence interval [CI] 1.00–1.11; p=0.04) and increased perioperative blood loss (OR 1.002; 95% CI 1.000–1.003; p=0.03) were predictors of DGF. Protective factors included living donor (LD) grafts (OR 0.15; 95% CI 0.05–0.49; p=0.002) and intraoperative graft urine production (OR 0.39; 95% CI 0.23–0.65; p

Although general guidelines exist directing the management of new/novel oral anticoagulants (NOACs) in the perioperative period for open/endoscopic procedures, no consensus exists for those patients being considered for shockwave lithotripsy (SWL). To gauge current practice, we administered a survey to the international endourologic community.A web-based survey was sent to current Endourological Society members. Respondents were asked whether they would consider SWL in patients receiving NOACs, and if they used SWL how these agents were managed perioperatively. Respondents were also asked which physicians in the patients' circle of care managed the discontinuation and reinstitution of the drugs.There were 165 respondents from 27 countries. Approximately 92.7% of urologists had access to SWL but only 53.4% indicated they would offer SWL to patients receiving NOACs. Among these urologists, 63.3% relied on internal medicine/hematology/cardiology colleagues to counsel patients on the discontinuation of NOACs pretreatment, whereas the majority (64%) handled the resumption guidance themselves. There was wide variability in the management of NOACs before lithotripsy, with discontinuation varying from 2 to 7 days. Resumption was more consistent, ranging from 1 to 2 days or when hematuria resolved. None of the respondents reported knowledge of adverse effects such as perinephric hematomas or cardiovascular morbidity.A large percentage of globally surveyed endourologists do not offer SWL to patients who are taking NOACs. Among those that do offer SWL, there seems to be a absence of consensus on optimal duration of discontinuation, suggesting a need to establish evidence-based guidance to optimize patient outcomes.

INTRODUCTION AND OBJECTIVE:The role of stenting prior to shock wave lithotripsy (SWL) of large renal stones is controversial. Some believe that stents reduce the risk of ureteral obstruction from s...

Introduction: The role of ureteric stenting in renal transplant has been well-demonstrated. The goal of this survey was to determine the use of ureteric stents by Canadian transplant surgeons and how the ureteroneocystotomy and followup is performed. Methods: An online survey was sent to the 40 surgeon members of the Canadian Society of Transplantation. The primary outcome was the rate of ureteric stent use at the time of renal transplantation. The secondary outcomes were the ureteric stent dwell time, use and type of prophylactic antibiotics, and the use of routine post-transplant ultrasonography. Results: All respondents (25) used ureteric stent routinely and 92% remove the stent between four and six weeks postoperatively. Prophylactic antibiotics were used 64% of the time for ureteric stent removal. The majority of surgeons do not routinely perform a post-stent removal ultrasound. Fifty-six percent of respondents perform a refluxing anastomosis. Conclusions: Ureteric stents are routinely used in renal transplant in Canada. Areas for improvement and topics of debate identified from this survey are the need for peri-stent removal antibiotics, the role of post-stent removal ultrasound, the duration of stent dwell time, and the need for a non-refluxing ureteroneocystotomy.

Introduction: After the introduction of shock wave lithotripsy (SWL), ureteroscopy (URS), and percutaneous nephrolithotomy (PCNL), the subspecialty of endourology was born in the late 1970s. The purpose of this study was to report milestones in Canadian endourology, highlighting Canada’s contributions to the field. Methods: A review of the literature was performed from the late 1970s to the present. The literature review included bibliographic and digital resources. Additionally, records and recollections by various individuals were used, including some directly involved. Results: Endourology was born in Canada when SWL, URS, and PCNL emerged as minimally invasive treatment options for stones in the early to mid-1980s. According to our research, the first PCNL was performed at the University of Toronto in 1981. Dr. Joachim Burhenne, a Harvard-trained radiologist from Germany, first used extracorporeal SWL in Canada at the University of British Columbia (UBC) for the treatment of biliary stones. Treatment for urinary tract stones followed at UBC and Dalhousie University. The first worldwide use of the holmium laser for lithotripsy of urinary tract calculi took place at the University of Western Ontario. Other endourology milestones in Canada include the formation of the Canadian Endourology Group and the emergence of the Endourological Society-accredited fellowship programs at the University of Toronto and Western University in the 1990s. Canada hosted the 21st and 35th World Congress of Endourology and Shock Wave Lithotripsy annual meeting in Montreal and Vancouver, respectively. Conclusions: Canadian urologists have led many advances in SWL, URS, and PCNL over the past four decades, and for a relatively small community have made significant contributions to the field. Through the training of the next generation of endourologists at Canadian institutions, the future of endourology in Canada is bright.

Introduction: Stone migration during ureteroscopy (URS) for proximal ureteric calculi is a constant challenge. Several retropulsion prevention devices have been developed to optimize URS outcomes. Our technique involves capturing the stone within a fourwire Nitinol stone basket and then performing laser lithotripsy to dust the stone while it is engaged in the basket. The dusted fragments wash out with the irrigation fluid and once small enough, the remaining stone is removed intact.Methods: A retrospective chart review was performed of all proximal semi-rigid URS procedures for a solitary calculus (2000– 2016). We compared our new technique introduced in 2010 to URS control procedures that did not use retropulsion prevention techniques or devices.Results: One hundred and forty patients underwent URS for proximal ureteric calculi. Mean stone diameter was 9.3±3.4 mm, with similar impaction rate between both groups (44.1% vs. 43.1% control; p=n/s). The mean surgical procedure time was 53.3±17.9 minutes for the new technique and 65.2±29.2 minutes for the control group (p=0.005). Compared to the new technique, the control group had a higher rate of retropulsion (33.3% vs. 14.7%; p=0.01) and required flexible URS more often to exclude or remove residual fragments (24.1% vs. 59.1%; p=0.001). Using the new technique, stone-free rates were higher (79.1% vs. 69.4%; p=n/s) and there was a lower likelihood of leaving residual fragments both

Introduction: The purpose of this study was to determine the variety and prevalence of renal and non-renal abnormalities detected on multidetector computed tomography (MDCT) that precluded patients from donating a kidney.Methods: Institutional review board approval was obtained and the requirement for informed consent was waived. A retrospective, single-centre review of 701 patients (444 female, 257 male; age range 18–86 years; mean age 43.2±11.9 years) that underwent renal donor protocol MDCT was conducted. A systematic review of the CT report, records from multidisciplinary renal transplantation rounds, and electronic medical records was performed to determine which patients were approved or declined as live renal donors. If declined as a donor, CT-identified reasons were categorized as abnormalities of renal vasculature, renal parenchyma, collecting system, or extra-renal.Results: A total of 81 patients were excluded as renal donors on the basis of CT findings. Abnormalities of the collecting system accounted for the most frequent cause of exclusion (n=41), with asymptomatic renal calculi being detected in 39 patients. Complex vascular anatomy and vascular abnormalities resulted in the exclusion of 29 patients. Supernumerary arteries and early arterial branching resulted in the exclusion of 20 patients, while renal vein anomalies leading to exclusion were uncommon (n=2). Abnormalities of renal parenchyma resulted in the exclusion of nine patients. Three patients were diagnosed with autosomal dominant polycystic kidney disease, two patients had renal cell carcinoma, and two patients had areas of cortical scarring. A complex cystic lesion requiring surveillance imaging was encountered in one patient and a large area of renal infarction related to prior adrenalectomy was demonstrated in one patient. Extra-renal abnormalities leading to exclusion were limited to two patients with pulmonary nodules.Conclusions: MDCT plays a critical role in the preoperative assessment of potential renal donors by identifying contraindications to donor nephrectomy and providing accurate vascular mapping. This study is anticipated to be informative for those involved in the workup of potential living renal donors by quantifying the incidence and reasons for donor exclusion identified on CT.

We examined temporal changes in the demographics of patients undergoing definitive treatment for kidney stones during a 20-year period in Ontario, Canada.Using the Ontario Health Insurance Plan physician claims database and the Canadian Institute for Health Information Discharge Abstract Database we performed a population based cross-sectional time series analysis by identifying all kidney stone treatments done between July 1, 1991 and December 31, 2010. The demographics assessed were patient gender, age and socioeconomic status. The rate and/or proportion of kidney stone treatments per strata of these demographics were calculated for each 1-year block of the study period. We used time series analysis with exponential smoothing and autoregressive integrated moving average models to assess for trends with time.We identified 116,115 patients who underwent treatment for kidney stones during the study period. The rate of stone procedures performed per year increased steadily from 85/100,000 to 126/100,000 population. With time the rate of females who were treated increased significantly from 40/100,000 to 53/100,000 (p0.0001). In contrast, the rate of males who were treated remained stable, increasing from 82/100,000 to 83/100,000 (p = 0.11). In regard to age the rate of patients older than 64 years increased significantly with time from 67/100,000 to 89/100,000 (p0.0001). In regard to socioeconomic status approximately 20% of the patients were in each of the 5 income quintiles during the entire study period.Our population based study shows an increased rate of females and of patients older than 64 years undergoing definitive treatment for kidney stones with time.

To develop a unique simulation-based assessment using a laparoscopic inferior vena cava (IVC) injury scenario that allows for the safe assessment of urology resident's technical and nontechnical skills, and investigate the effect of personality traits performance in a surgical crisis.Urology residents from our institution were recruited to participate in a simulation-based training laparoscopic nephrectomy exercise. Residents completed demographic and multidimensional personality questionnaires and were instructed to play the role of staff urologist. A vasovagal response to pneumoperitoneum and an IVC injury event were scripted into the scenario. Technical and nontechnical skills were assessed by expert laparoscopic surgeons using validated tools (task checklist, GOALS, and NOTSS).Ten junior and five senior urology residents participated. Five residents were unable to complete the exercise safely. Senior residents outperformed juniors on technical (checklist score 15.1 vs 9.9, p0.01, GOALS score 18.0 vs 13.3, p0.01) and nontechnical performance (NOTSS score 13.8 vs 10.1, p = 0.03). Technical performance scores correlated with NOTSS scores (p0.01) and pass/fail rating correlated with technical performance (p0.01 for both checklist and GOALS), NOTSS score (p = 0.02), and blood loss (p0.01). Only the conscientiousness dimension of the big five inventory correlated with technical score (p = 0.03) and pass/fail rating (p = 0.04).Resident level of training and laparoscopic experience correlated with technical performance during a simulation-based laparoscopic IVC injury crisis management scenario, as well as multiple domains of nontechnical performance. Personality traits of our surgical residents are similar and did not predict technical skill.

Papillary renal cell carcinoma (PRCC) has 2 histologic subtypes. Almost half of the cases fail to meet all morphologic criteria for either type, hence are characterized as PRCC not otherwise specified (NOS). There are yet no markers to resolve the PRCC NOS category. Accurate classification can better guide the management of these patients. In our previous PRCC study we identified markers that can distinguish between the subtypes. A PRCC patient cohort of 108 cases was selected for the current study. A panel of potentially distinguishing markers was chosen from our previous genomic analysis, and assessed by immunohistochemistry. The panel exhibited distinct staining patterns between the 2 classic PRCC subtypes; and successfully reclassified the NOS (45%) cases. Moreover, these immunomarkers revealed a third subtype, PRCC3 (35% of the cohort). Molecular testing using miRNA expression and copy number variation analysis confirmed the presence of 3 distinct molecular signatures corresponding to the 3 subtypes. Disease-free survival was significantly enhanced in PRCC1 versus 2 and 3 (P=0.047) on univariate analysis. The subtypes stratification was also significant on multivariate analysis (P=0.025; hazard ratio, 6; 95% confidence interval, 1.25-32.2). We propose a new classification system of PRCC integrating morphologic, immunophenotypical, and molecular analysis. The newly described PRCC3 has overlapping morphology between PRCC1 and PRCC2, hence would be subtyped as NOS in the current classification. Molecularly PRCC3 has a distinct signature and clinically it behaves similar to PRCC2. The new classification stratifies PRCC patients into clinically relevant subgroups and has significant implications on the management of PRCC.

Purpose: We evaluate population based trends in the use of extracorporeal shock wave lithotripsy, ureteroscopy and percutaneous nephrolithotomy during the last 20 years, as well as assess the re-treatment rate and morbidity from treatment over time.Materials and Methods: Using administrative databases in the province of Ontario, Canada, a population based cross-sectional time series analysis was performed between July 1, 1991 and December 31, 2010. All extracorporeal shock wave lithotripsy, ureteroscopy and percutaneous nephrolithotomy procedures were identified, along with all hospital readmissions and emergency department visits within 7 days of treatment. The primary outcome was treatment use, and secondary outcomes were the need for ancillary treatment and hospital readmission or emergency department visit after treatment. Exponential smoothing and autoregressive integrated moving average (ARIMA) models were used to assess trends over time.Results: We identified 194,781 kidney stone treatments perform...

A baseline kidneys, ureters, and bladder (KUB) radiograph, at the time of computed tomography (CT) for ureteral stones, might aid interpretation of future KUBs. The CT scout radiograph might render the baseline KUB redundant, however. We sought to assess the diagnostic utility of baseline KUB for patients with ureteral stones.Patients with ureteral stones were retrospectively identified. All had a baseline KUB in addition to CT and were reassessed after 4 to 60 days with KUB. Each patient's imaging was randomized 1:1 into either "KUBCT" or "CT" groups. Three urologists independently assessed the imaging: CT (with scout film) and baseline KUB in the KUBCT group, but only the CT (not KUB) in the CT group. Definitive stone assessment on follow-up KUB was defined as all three reviewers answering either Yes or No (not Indeterminate) to the question of stone passage or migration.Of 154 stones, the mean diameter was 4.8 ± 2.1 mm, density was 914 ± 300 Hounsfield units (HU), with 54.4% in the distal ureter. Stone visibility was 60.4% on KUB vs 43.5% on scout film (P0.001). Scout film visibility favored the CT group (52.7 vs 35.0%, P = 0.027). After adjusting for body mass index, skin-to-stone distance, size, density, and location, definitive assessment rates were higher in the KUBCT group (P = 0.047). When reviewers reassessed the CT group using the baseline KUB, they were able to do so definitively in an additional 16 (21.6%, P0.001). Definitive assessments were associated with higher rates of stone visibility on scout film (86.1 vs 21.1%, P0.001), KUB (86.1 vs 50.0%, P0.001), and larger (6.0 vs 3.7 mm, P0.001), denser stones (1046 vs 802 HU, P0.001).The addition of a baseline KUB to the CT scout film improves the ability of urologists to determine stone outcome when following patients with KUB imaging and might reduce the subsequent need for additional imaging.

We set out to provide an overview of the most recent evidence for medical expulsive therapy (MET). Conflicting level 1 evidence for and against the use of MET has been published. The largest double-blind randomized control trial (1110 patients) comparing placebo, tamsulosin, and nifedipine found no benefit for MET in preventing the need for secondary intervention. A recent meta-analysis of 55 randomized trials using alpha-blockers suggests that no benefit is seen with smaller ureteric calculi, but patients with larger ureteric calculi experience shorter times to stone passage, fewer episodes of pain, require less surgical intervention, and fewer hospital admissions. All the major urological organizations (American Urological Association, European Association of Urology, Canadian Urological Association) suggest offering MET as part of conservative management for appropriate patients with ureteric calculi. MET is a reasonable option for conservative management of ureteric calculi that may avoid the need for surgical intervention. The greatest benefit is likely seen with alpha-blockers and calculi ≥5 mm in the distal ureter. Expanding indications for the use of MET include facilitating stone fragment clearance after SWL. MET appears to be safe for use in pregnant and pediatric patients.

Shock wave lithotripsy (SWL) remains the only effective truly non-invasive treatment for nephrolithiasis. While single-treatment success rates may not equal those of ureteroscopy and percutaneous nephrolithotomy, it has an important role to play in the management of stones. In this paper, we outline the latest evidence-based recommendations for maximizing SWL outcomes, while minimizing complications. A comprehensive review of the current literature was performed regarding maximizing SWL outcomes. Several different considerations need to be made regarding patient selection with respect to body habitus, body mass index, anatomical location and underlying urologic abnormalities. Stone composition and stone density (Hounsfield Units) are important prognostic variables. Patient positioning is critical to allow for adequate stone localization with either fluoroscopy or ultrasound. Coupling should be optimized with a low viscosity gel applied to the therapy head first and patient movement should be limited. SWL energy should be increased slowly and shockwave rates of 60 or 90 Hz should be used. Medical expulsive therapy with alpha-blockers after SWL treatment has shown benefit, particularly with stones greater than 10 mm. While single-treatment success rates may not equal those of ureteroscopy or percutaneous nephrolithotomy, with proper patient selection, optimization of SWL technique, and use of adjunctive treatment after SWL, success rates can be maximized while further reducing the already low rate of serious complications. SWL remains an excellent treatment option for calculi even in 2017.

Purpose: This study presents a comparison of the international experience with ipsilateral and bilateral ureteroscopy for multiple, bilateral ureteral and renal stones vs single stone treatment. Patient and treatment characteristics and outcomes were compared. Materials and Methods: The CROES (Clinical Research Office of the Endourological Society) Ureteroscopy Global Study includes 114 centers in 32 countries. Patients undergoing bilateral ureteroscopy, ipsilateral ureteroscopy for multiple stones and ureteroscopy for a single stone were examined from January 2010 to October 2012. Intraoperative characteristics and postoperative outcomes were identified for each patient. Inverse probability weighted regression adjustment analyses were done to compare outcomes independent of differences among centers and patient characteristics. Results: The CROES Ureteroscopy Global Study consists of 11,885 patients. A total of 2,153 patients (18.7%) were treated for multiple stones, of whom 1,880 (87.3%) and 273 (12.7%) underwent ipsilateral and bilateral ureteroscopy, respectively. Inverse probability weighted regression adjustment models for bilateral vs ipsilateral ureteroscopy and multiple vs single stone treatments showed that patients with bilateral ureteroscopy and multiple stone treatments had lower stone-free rates, higher re-treatment rates and longer operative times compared to patients who underwent ipsilateral ureteroscopy and single stone treatment. There was no difference in complication rates among bilateral, ipsilateral and single stone ureteroscopy. Conclusions: This study presents a large series of patients who underwent bilateral and ipsilateral ureteroscopy. Our findings suggest a decrease in stone-free rates, increased re-treatment rates, increased operative times and longer hospital stay in patients treated for multiple stones. The treatment of multiple stones and bilateral ureteroscopy are safe compared to single stone treatment and ipsilateral ureteroscopy, respectively., Boston Scientific

Background and Purpose: Throughout the literature, the ureter is described as having three anatomic sites of narrowing at which kidney stones typically become lodged: The ureteropelvic junction (UPJ), the ureteral crossing of the iliac vessels, and the ureterovesical junction (UVJ). There is little evidence to support this notion, however. The purpose of our study is to evaluate whether three peaks in stone distribution corresponding to these anatomic landmarks exist. Methods: We retrospectively reviewed the kidneys-ureters-bladder (KUB) films of 622 patients with solitary ureteral calculi referred for shockwave lithotripsy (SWL). Pretreatment KUB films were used to categorize the location of their ureteral stone relative to 1 of 19 levels referenced to the axial skeleton. CT scans of 74 patients were used to determine the location of the UPJ, ureteral crossing of the iliac vessels, and UVJ relative to the 19 levels on KUB radiography. Histograms were then constructed to plot the distribution of ...