Diagnostic accuracy of dual-energy computed tomography (DECT) to differentiate uric acid from non-uric acid calculi: systematic review and meta-analysis.

BACKGROUND: Uric acid stone diagnosis is presently done primarily with in vitro analysis of stones. In vivo diagnosis with dual-energy CT (DECT) would allow earlier initiation of therapy with urine alkalinization and avoid surgical intervention. OBJECTIVE: To evaluate if DECT, using stone analysis as reference standard, is sufficiently accurate to replace stone analysis for diagnosis of uric acid stones. METHODS: Original studies in patients with urolithiasis examined with DECT with stone analysis as the reference standard were eligible for inclusion. MEDLINE (1946-2018), Embase (1947-2018), CENTRAL (August 2018), and multiple urology and radiology conferences were searched. QUADAS-2 was used to assess risk of bias and applicability. Meta-analyses were performed using a bivariate random-effects model. RESULTS: A total of 21 studies (1105 patients, 1442 stones) were included. Fourteen studies containing 662 patients (944 stones) were analyzed in the uric acid dominant target condition (majority of stone composition uric acid): mean sensitivity was 0.88 (95% CI 0.79-0.93) and specificity 0.98 (95% CI 0.96-0.99). Thirteen studies (674 patients, 760 stones) were analyzed in the uric acid-containing target condition (< majority of stone composition uric acid): mean sensitivity was 0.82 (95% CI 0.73-0.89) and specificity 0.97 (95% CI 0.94-0.98). Meta-regression showed no significant variability in test accuracy. Two studies had one or more domains at high risk of bias and there were no concerns regarding applicability. CONCLUSION: DECT is an accurate replacement test for diagnosis of uric acid calculi in vivo, such that stone analysis could be replaced in the diagnostic pathway. This would enable earlier initiation of urine alkalinization. KEY POINTS: • DECT for uric acid dominant stones has sensitivity of 0.88 (95% CI 0.79-0.93) and specificity of 0.98 (95% CI 0.96-0.99); uric acid-containing stones had mean sensitivity of 0.82 (95% CI 0.73-0.89) and specificity of 0.97 (95% CI 0.94-0.98). • Meta-regression did not identify any variables (study design, reference standard, dual-energy CT type, dose, risk of bias) that influenced test accuracy. • Only 2 of the 21 included studies had 1 or more domain considered to be at high risk of bias with the majority of domains considered at low risk of bias; there were no concerns regarding applicability in any of the included studies.

Micro cost-effectiveness analysis of standard vs. mini percutaneous nephrolithotomy A single Canadian institution's experience.

INTRODUCTION: Mini-percutaneous nephrolithotomy (mPCNL ) has been described as an alternative to standard nephrolithotomy (sPCNL ) for select stones. Studies suggest that mPCNL has comparable stone-free rates, with potential for decreased complications and shorter hospital stay. Costs associated with both procedures present a challenge to Canadian institutions due to capital acquisitions of equipment and ongoing disposables. The objective of this study was to compare the cost-effectiveness of both procedures at our institution. METHODS: A decision tree analytic model was developed to compare costs and outcomes of both procedures. Primary outcomes included assessment of total capital, operative, and hospitalization costs. Cost and outcome of peri- and postoperative parameters were obtained using a retrospective analysis of 20 mPCNL and 84 sPCNL procedures on 1-2.5 cm stones between January 2020 and June 2022, and supplemented with internal hospital expenditure records and literature outcome data. Descriptive statistics and regression models were performed. RESULTS: The estimated total cost-per-patient was $7427.05 and $5036.29 for sPCNL and mPCNL, respectively, resulting in cost-savings of $2390.76 in favor of mPCNL, with a comparable stone-free rate. The savings were due to lower costs associated with complications and hospital stay. mPCNL had higher capital costs ($95 116.00) compared to sPCNL ($78 517.00), but per-procedure operative costs were lower for mPCNL ($2504.48) compared to sPCNL ($3335.72). Cost-per-case regression of total costs intersected at 5.51 cases when accounting for operative and hospitalization costs, and at 20 cases when only considering operative costs. CONCLUSIONS: Despite higher upfront costs, mCPNL may represent a valid, cost-effective alternative to sPCNL for select stones due to clinical and economic benefits in Canadian institutions.

Pre-Peritoneal Dialysis Peritonitis After Saline Infusion Sonohysterogram in a Patient With an Embedded Catheter: A Case Report.

Rationale: Clear guidelines currently exist regarding antibiotic prophylaxis for patients on peritoneal dialysis (PD) prior to common diagnostic procedures. However, these guidelines do not include patients with subcutaneously embedded PD catheters who are awaiting PD initiation although both these populations share a great deal of risk factors for infections. Issues regarding antibiotic prophylaxis and avoidable infections are bound to keep occurring if physicians are not conscious of the risks of infections shared by all patients suffering from renal failure. Presenting concerns: Two weeks after a saline infusion sonohysterography (SIS), a 48-year-old woman with chronic kidney disease (CKD) G5 ND, type 2 diabetes, a subcutaneously embedded PD catheter, and prior abnormal uterine bleeding presented to the emergency department complaining of nausea, vomiting, diarrhea, weakness, and abdominal pain. The patient received no antibiotic prophylaxis prior to her SIS. Diagnoses: The final diagnosis of peritonitis was established after acute kidney injury, gastroenteritis, and small bowel obstruction were considered and ruled out. A delay in the final diagnosis occurred because of the complex presentation, the fact that the patient had not yet initiated PD, and the presence of concomitant anion gap metabolic acidosis and an acute elevation of the patient's creatinine. Interventions: The patient was started on broad-spectrum intravenous antibiotics when the diagnosis of peritonitis was established. Insulin and intravenous bicarbonate infusions were used to correct the patient's anion gap metabolic acidosis. Surgical debridement of the necrotic subcutaneous tissue and removal of the embedded PD catheter were necessary. Outcomes: The patient's infection resolved completely as did her anion gap metabolic acidosis. The patient had to transfer permanently from PD to hemodialysis for her renal replacement therapy. Teaching points: This case report serves as a good reminder that physicians should keep in mind the possibility of peritonitis in patients with embedded PD catheters. As these patients are also at risk of infections, antibiotic prophylaxis should be used in patients with embedded catheters in the same way it is used for PD patients prior to obstetrical, gynecological, or gastrointestinal procedures.

Justification: Il existe des directives claires quant à la prophylaxie antibiotique à utiliser préalablement aux procédures de diagnostic courantes chez les patients sous dialyse péritonéale (DP). Les patients disposant d'un cathéter de DP implanté sous-cutané en attendant le début de la dialyse ne sont pas inclus dans ces recommandations, même si cette population partage plusieurs facteurs de risque d'infections avec les patients déjà sous DP. Des enjeux liés à la prophylaxie antibiotique et aux infections évitables continueront de se poser si les médecins ignorent les risques d'infections partagés par tous les patients souffrant d'insuffisance rénale. Présentation du cas: Une femme âgée de 48 ans atteinte d'insuffisance rénale chronique (IRC) G5 ND et de diabète de type 2 s'étant présentée aux urgences deux semaines après une sono-hystérographie (SHG) avec infusion intra-utérine de solution saline. La patiente portait un cathéter de PD implanté sous-cutané et avait déjà eu des saignements utérins anormaux dans le passé. Elle se plaignait de nausées, de vomissements, de diarrhées, de faiblesse générale et de douleurs abdominales. Elle n'avait reçu aucune prophylaxie antibiotique avant la SHG. Diagnostic: Le diagnostic final de péritonite a été établi après que l'insuffisance rénale aiguë, la gastro-entérite et une obstruction de l'intestin grêle aient été envisagées et écartées. Le diagnostic final a été retardé en raison de la présentation complexe, du fait que la patiente n'avait pas encore amorcé la DP et de la présence concomitante d'une acidose métabolique à trou anionique et d'une élévation subite de la créatinine. Interventions: La patiente a reçu des antibiotiques à large specter par voie intraveineuse lorsque le diagnostic de péritonite a été établi. Des infusions d'insuline et de bicarbonate par voie intraveineuse ont été utilisées pour corriger l'acidose métabolique à trou anionique. Un débridement chirurgical des tissus sous-cutanés nécrosés et l'ablation du cathéter PD se sont avérés nécessaires. Résultats: L'infection a guéri complètement, tout comme l'acidose métabolique à trou anionique. La patiente a dû passer définitivement de la DP à l'hémodialyse pour son traitement de suppléance rénale. Enseignements tirés: Ce cas illustre bien que les médecins devraient toujours garder les risques de péritonite à l'esprit lorsqu'ils traitent des patients portant un cathéter de PD implanté sous-cutané. Puisque ces patients présentent eux aussi un risque d'infection, la prophylaxie antibiotique devrait leur être administrée avant les procédures obstétricales, gynécologiques ou gastro-intestinales, comme c'est le cas pour les patients sous DP.

The impact of measuring split kidney function on post-donation kidney function: A retrospective cohort study.

BACKGROUND: Studies have reported agreement between computed tomography (CT) and renography for the determination of split kidney function. However, their correlation with post-donation kidney function remains unclear. We compared CT measurements with renography in assessment of split kidney function (SKF) and their correlations with post-donation kidney function. METHODS: A single-centre, retrospective cohort study of 248 donors from January 1, 2009-July 31, 2019 were assessed. Pearson correlations were used to assess post-donation kidney function with renography and CT-based measurements. Furthermore, we examined high risk groups with SKF difference greater than 10% on renography and donors with post-donation eGFR less than 60 mL/min/1.73m2. RESULTS: 62% of donors were women with a mean (standard deviation) pre-donation eGFR 99 (20) and post-donation eGFR 67 (22) mL/min/1.73m2 at 31 months of follow-up. Post-donation kidney function was poorly correlated with both CT-based measurements and renography, including the subgroup of donors with post-donation eGFR less than 60 mL/min/1.73m2 (r less than 0.4 for all). There was agreement between CT-based measurements and renography for SKF determination (Bland-Altman agreement [bias, 95% limits of agreement] for renography vs: CT volume, 0.76%, -7.60-9.15%; modified ellipsoid,1.01%, -8.38-10.42%; CC dimension, 0.44%, -7.06-7.94); however, CT missed SKF greater than 10% found by renography in 20 out 26 (77%) of donors. CONCLUSIONS: In a single centre study of 248 living donors, we found no correlation between CT or renography and post-donation eGFR. Further research is needed to determine optimal ways to predict remaining kidney function after donation.

Use of video education in postoperative patient counselling: A quality improvement initiative.

INTRODUCTION: This quality improvement study examined if a video-based resource could reduce delayed discharges after robotic prostatectomy while maintaining high levels of patient satisfaction. METHODS: From April 2018 to February 2020, all patients undergoing robotic-assisted radical prostatectomy (RARP) were asked to complete an anonymous survey evaluating their perioperative experience. The quality improvement (QI) intervention started in March 2019 with a series of six educational videos being shown to all patients. The videos were used to supplement postoperative instruction. The discharge times of all patients were obtained from The Ottawa Hospital Data Repositories. A run chart analysis was used to detect change in discharge time (outcome measure). Patient satisfaction (balancing measure) was analyzed using Chi-squared analysis and descriptive statistics. RESULTS: A total of 425 robotic prostatectomies (199 pre-intervention, 226 post-intervention) were available. Analysis of the run chart revealed non-random change favoring earlier discharge in the intervention group (p<0.05), with a pre-intervention late discharge rate of 64% and a post-intervention late discharge rate of 55%. A total of 140 surveys (59 pre-intervention, 81 post-intervention) assessing patient satisfaction were completed, corresponding with a response rate of 29.6% and 35.8%, respectively. Median score on a 10-point scale for overall satisfaction was equal between the intervention and non-intervention groups (9 [interquartile range (IQR 8-10) vs. 10 [IQR 8-10], p=0.92). CONCLUSIONS: Patient satisfaction with care and education was high for all patients and was not negatively impacted by this intervention. Video education tools may be one method to help improve the discharge process following RARP.

Transplanting kidneys from donors with small renal masses - a strategy to expand the donor pool.

INTRODUCTION: Renal transplantation is the optimal treatment for end-stage renal disease, but organ demand continues to outstrip supply. The transplantation of kidneys from donors with small renal masses (SRMs) represents a potential avenue to expand the donor pool. We reviewed all published cases of transplants from donors with SRMs and we present followup data, best practices, and outline an actionable series of steps to guide the implementation of such transplants at individual centers. METHODS: A detailed literature search of the MEDLINE/PubMed and SCOPUS databases was performed. Thirty unique data sets met inclusion criteria and described the transplantation of tumor-ectomized kidneys; nine data sets described the transplantation of contralateral kidneys from donors with SRMs. RESULTS: A total of 147 tumorectomized kidneys have been transplanted. Pathology revealed 120 to be renal cell carcinomas (RCCs), of which 116 were stage T1a (0.3-4 cm). The mean followup time was 44.2 months (1-200). A single suspected tumor recurrence occurred in one patient nine years post-transplantation and it was managed with active surveillance. Twenty-seven kidneys have been transplanted from deceased donors with contralateral renal masses. Pathology revealed 25 to be RCCs, of which 19 were confirmed to be stage T1 (<7 cm). The mean followup time was 46.7 months (0.5-155). One recipient developed an RCC and underwent curative allograft nephrectomy. CONCLUSIONS: Careful use of kidneys from donors with SRMs is feasible and safe, with an overall recurrence rate of less than 1.5%. The use of such kidneys could help alleviate the organ shortage crisis.

Perceptions and Practice Patterns of Holmium Laser Goggles in Endourological Procedures: An Unnecessary Evil?

PURPOSE: The holmium laser is used increasingly for a wide array of urological procedures. Laser safety goggles are mandatory at many centers for individuals within the nominal hazard zone, as set out by the institution. Recent ex vivo studies suggest standard eye wear may be equally as protective. We sought to evaluate the perceptions and practice patterns of laser safety goggles in urology. MATERIALS AND METHODS: A 24-question survey was sent out through e-mail to an international e-mail list of ∼2000 urologists that were members of the Endourological Society. Data were collected anonymously using Survey Monkey. RESULTS: A total of 264 (14%) urologists completed the survey. Thirty-four percent worked in the community, whereas 63% worked at an academic institution. Ninety-seven percent routinely used the holmium laser. The most common uses were lithotripsy (99%), tissue incision (71%), tumor ablation (58%), and prostate ablation (26%). Formal laser training and institutional laser safety policies were reported in 76% and 64%, respectively. Forty percent of respondents routinely wore laser safety goggles. Laser adverse events were witnessed by 19%, but there were no eye injuries reported. Seventy percent of surgeons felt that laser safety goggles may impair their vision. When presented with the information that regular eye glasses may be as effective as laser goggles for preventing harm, the majority (86%) would opt for regular eye wear. CONCLUSIONS: Laser safety eyewear practice patterns vary greatly. Many centers have adopted policies for universal mandatory laser goggles in the operating room. With over two thirds of surgeons suggesting laser goggles impair their vision, and recent literature suggesting regular eye wear is equivalent in preventing laser-associated eye injuries, laser goggle safety policies should be updated to better match the potential hazards inherent to the device.

Successful Initiation of Dialysis with a 20-Year-Old Buried Peritoneal Dialysis Catheter: Case Report and Literature Review.

Buried peritoneal dialysis (PD) catheters are typically inserted several weeks or months before the anticipated need for dialysis. Occasionally, renal function unexpectedly stabilizes after the surgery, and a patient may go years before the catheter is needed. We report a case of successful initiation of PD with a twenty-year-old buried catheter. We outline the steps needed to optimize the catheter function and review the benefits of the buried PD catheter.

Laparoscopic pyeloplasty practice patterns in Canada.

INTRODUCTION: Ureteropelvic junction obstruction (UPJO) is a condition characterized by partial or complete obstruction of urine transport from the renal pelvis to the ureter and can present with intermittent flank pain, recurrent urinary tract infections, renal stones, or renal dysfunction. While historically, open pyeloplasty was the gold standard for surgical management, laparoscopic methods to repair UPJO have largely taken over as the preferred approach for adolescent and adult patients. Despite near universal adoption of laparoscopic pyeloplasty among Canadian urologists, it remains a technically complex procedure and considerable variability exists in the procedural steps performed. METHODS: An online survey was distributed to all urologists registered with the Canadian Urology Association (CUA). Participants were asked to describe their training background, comfort level with laparoscopic pyeloplasty, positioning preferences, procedural steps, and stenting practices. RESULTS: A total of 100 board-certified urologists completed our survey, with approximately half from a community setting and half with academic affiliations (56% and 43%, respectively). The vast majority (98%) reported preferring the Anderson-Hynes (dismembered) pyeloplasty technique. Other technical steps of the procedure were variable among respondents, with no discernable pattern. Those who felt most comfortable with the procedure tended to perform a larger volume of laparoscopic pyeloplasties annually or work at higher-volume institutions. CONCLUSIONS: Laparoscopic pyeloplasty remains a technically challenging procedure that many Canadian urologists are uncomfortable performing. With this publication, we hope to create discussion among urologists and to reveal procedural tips that may improve comfort in tackling these complex cases.

In Search of a Simple and Reliable Method of Measuring Intra-abdominal Pressure in Peritoneal Dialysis Patients.

BACKGROUND: Patients treated with peritoneal dialysis (PD) are at increased risk of developing mechanical complications such as dialysate leaks and hernias thought to be partially related to an increase in intra-abdominal pressure (IAP) secondary to dialysate in the abdomen. However, measurement of IAP requires specialized equipment that is not readily available in the home dialysis unit. OBJECTIVES: To develop a reliable method of measuring IAP in PD patients that could be easily used in the home dialysis unit. We hypothesized that the handheld Stryker pressure monitor would be suitable for this purpose via connection to the PD catheter. DESIGN: Cross-sectional. SETTING: Tertiary Care Hospital, Ottawa, Ontario, Canada. PATIENTS: Patients who were having a PD catheter inserted via laparoscopic surgery at The Ottawa Hospital were recruited for the study. MEASUREMENTS: With the patients at end-expiration, the IAP measured with the Stryker monitor connected to the PD catheter was compared with the insufflator pressures of 15, 10, and 5 mm Hg. METHODS: Bland-Altman plots were constructed and intraclass correlation coefficients were calculated for each pressure. RESULTS: Twelve patients participated in the study: 9 men and 3 women. They were on average 53 ± 15 years old and 81 ± 13.4 kg. Two patients had to be excluded from the analysis due to difficulties zeroing the Stryker pressure monitor at the time of surgery. There were also rapid fluctuations in the insufflator pressure recording, creating additional challenges in comparing the 2 measurements at end-expiration. The 95% limits of agreement for the Bland-Altman plots ranged from 7.9 (@15 mm Hg) to 12.2 (@10 mm Hg). The intraclass correlation coefficients for reliability of the individual measurements ranged from 0.015 (10 mm Hg) to 0.634 (15 mm Hg). LIMITATIONS: Small sample size and lack of a gold standard comparator may have affected our results. CONCLUSIONS: In our study, we used the operating room insufflator as the gold standard for measuring IAP. By Bland-Altman plots and intraclass correlation coefficients, the pressure values obtained with the Stryker pressure monitor were not a reliable estimate of insufflator IAP especially at lower pressures. Further studies are needed to identify an ideal tool for measurement of IAP to guide PD management.

CONTEXTE: Les patients traités par dialyse péritonéale (DP) sont plus sujets aux complications mécaniques (hernies, fuites de dialysat) attribuées en partie à une augmentation de la pression intra-abdominale (PIA) due à l'accumulation de dialysat dans l'abdomen. La mesure de la PIA requiert toutefois de l'équipement spécialisé difficilement accessible en contexte de dialyse à domicile. OBJECTIF: Développer une méthode fiable, et facile à utiliser en contexte de dialyse à domicile, pour mesurer la PIA chez les patients traités par DP. Nous avons émis l'hypothèse qu'un tensiomètre portatif Stryker raccordé au cathéter de DP pourrait convenir à cet usage. TYPE D'ÉTUDE: Étude transversale. CADRE: Un centre de soins tertiaires d'Ottawa (Ontario) au Canada. SUJETS: Des patients de l'hôpital d'Ottawa à qui on avait inséré un cathéter de DP par chirurgie laparoscopique. MESURES: La pression intra-abdominale, mesurée en fin d'expiration à l'aide d'un tensiomètre Stryker raccordé au cathéter de DP, a été comparée aux pressions de 15, 10 et 5 mm Hg de l'insufflateur. MÉTHODOLOGIE: Des courbes de Bland-Altman ont été établies et des coefficients de corrélation intraclasse ont été calculés pour chaque mesure de pression. RÉSULTATS: Douze patients, soit neuf hommes et trois femmes, âgés de 53 ± 15 ans et pesant 81 ±13,4 kg en moyenne, ont participé à l'étude. Deux patients ont été exclus de l'analyse en raison de difficultés à remettre le tensiomètre Stryker à zéro au moment de l'intervention. On a observé de rapides fluctuations dans l'enregistrement de la pression avec l'insufflateur, ce qui a compliqué davantage la comparaison des deux mesures en fin d'expiration. Les limites de concordance à 95 % pour les courbes de Bland-Altman se situaient entre 7,9 (15 mm Hg) et 12,2 (10 mm Hg). Les coefficients de corrélation intraclasses pour la fiabilité des mesures individuelles s'échelonnaient entre 0,015 (10 mm Hg) et 0,634 (15 mm Hg). LIMITES: Les résultats sont limités par la faible taille de l'échantillon et l'absence d'étalon-or pour la comparaison. CONCLUSION: Pour cette étude, l'insufflateur de la salle d'opération a servi d'étalon-or pour la mesure de la PIA. Selon les courbes de Bland-Altman et les coefficients de corrélation intraclasses, les valeurs de pression obtenues avec le tensiomètre Stryker n'ont pas constitué une estimation fiable de la PIA de l'insufflateur, particulièrement pour les faibles valeurs de pression. Des études supplémentaires sont nécessaires pour proposer un outil de mesure fiable de la PIA afin de guider la gestion de la DP.

Characteristics and Outcomes of Exit Sites of Buried Peritoneal Dialysis Catheters: A Cohort Study.

Buried peritoneal dialysis (PD) catheters are placed months before dialysis is needed and the exit site is created when the catheter is dissected out at the initiation of dialysis. In contrast, the exit site of an unburied catheter is created by the surgeon at the time of insertion. We reviewed all patients who initiated PD at our center over a 2-year period. At each clinic visit, exit sites were subjectively classified into standard predefined groups. Outcomes of interest were the frequency of perfect exit sites at 2, 6, and 12 months and rate of exit-site infections (ESIs) at 90 days. One hundred and seventy-seven patients initiated PD during the period of interest, and 169, 157, and 144 remained on PD at 2, 6, and 12 months, respectively. Ninety-three patients had buried catheters, and 76 patients had unburied catheters. Both groups had similar frequency of perfect appearance of exit sites at 2, 6, and 12 months (37/93 vs 41/76 at 2 months; 54/87 vs 43/70 at 6 months; 50/ 81 vs 35/ 63 at 12 months in buried and unburied groups, respectively). More patients with buried catheters had ESIs in the first 3 months (7/93 vs 1/76, p = 0.059). We conclude that exit sites of buried PD catheters do not differ qualitatively from those of unburied catheters. The trend towards more ESIs with buried catheters suggests that there may be clinical consequences of the tissue trauma at time of exteriorization.

Long-term patient outcomes from the first year of a robotic surgery program using multi-surgeon implementation.

INTRODUCTION: There is concern that surgical quality initially declines during the learning phase of robotic surgery. At our institution, we used a multi-surgeon programmatic approach to the introduction of robotic surgery. The purpose of this study was to evaluate outcomes of patients treated during the first year of our program. METHODS: This is a historical cohort of all radical prostatectomy patients during a one-year period. Baseline, perioperative, and long-term followup data were prospectively and retrospectively collected. Treatment failure was a composite of any postoperative radiation, androgen-deprivation, or prostate-specific antigen (PSA) ≥0.2. RESULTS: During the study period, 225 radical prostatectomy procedures were performed (104 robotic and 121 open). Baseline characteristics were similar between groups (p>0.05). All patients were continent and 74% were potent prior to surgery. Mean estimated blood loss (280 cc vs. 760 cc; p<0.001) and blood transfusion (0% vs. 8.3%; p=0.002) was lower in the robotic cohort. Non-transfusion complications were similar between groups (13% vs. 12%; p=0.7). Mean hospital stay was shorter in the robotic cohort (1.4 vs. 2.5 days). There was no difference in overall positive margin rate (38% vs. 43%; p=0.4) or treatment failure at a median followup of 3.5 years (p=0.4). Robotically treated patients were more often continent (89% vs. 77%; p=0.02) and potent (48% vs. 32%; p=0.02). CONCLUSIONS: Using an inclusive multi-surgeon approach, robotic pros-tatectomy was introduced safely at a Canadian academic institution.

Practical comparison of four nitinol stone baskets.

BACKGROUND AND PURPOSE: The use of stone baskets for repositioning of stones or removal of fragment in conjunction with ureterorenoscopy has become widespread. We tested the performance of the ACMI Sur-Catch NT, Bard Dimension, Boston Scientific Zero-tip, and Cook N-Circle in a pig kidney model of flexible ureterorenoscopy. MATERIALS AND METHODS: Opening characteristics of the basket were measured with mechanical calipers at 1-mm increments and compared with published reports to ensure the tested baskets were representative. Pig kidneys were placed in a basin and the ureters secured with a suture to a weight for stability. Flexible renoscopy was performed using a 16F flexible cystonephroscope. An 8-mm calculus was placed in the lower pole. Using each of four designs, the time necessary to grasp the stone, time to release the stone, and total time to move a stone from the lower-pole calix to the upper-pole were recorded. Total time experiments were repeated six times with each basket by three surgeons for a total of 18 attempts, and catch-and-release experiments were repeated six times by four surgeons for a total of 24 attempts per basket. RESULTS: The Sur-Catch was significantly slower for catch and release (P < 0.001) and total time; P < 0.05) compared with all other baskets. There were no differences between the other baskets in either catch, release, or total times. There was no difference between surgeons (P < 0.0634) or between attempts one through six (P = 0.538). CONCLUSIONS: Baskets with added complexity of the wire configurations (Sur-Catch) or a deflectable-wire mechanism (Dimension) offer no advantages and may slow capture and release of stones.

The laparoscopic experience of recently trained Canadian urologists.

OBJECTIVE: While laparoscopy represents an increasingly important aspect of operative urology, the experience of Canadian urology trainees is poorly defined. The purpose of this study was to determine the level of laparoscopic training of Canadian urology trainees during residency as well as their comfort level with various laparoscopic techniques. METHODS: An e-mail-and web-based questionnaire was administered to the two most recent cohorts of Canadian-trained urologists (residencies completed in 2003 or 2004). A total of 50 questionnaires were sent. Overall laparoscopic experience and experience with specific laparoscopic tasks (e.g. colonic mobilization) were assessed. Subjects also reported on their relative comfort level (Likert scale of 1 to 5) with various laparoscopic procedures and tasks. Finally, attitudes towards the future role of laparoscopy in the practice of urology were determined. RESULTS: Thirty-six individuals (72%) responded to the questionnaire. Of the respondents, 28 (78%) were performing fellowships; of those pursuing fellowship training, 13 (36%) involved laparoscopy. Thirty-five respondents (97%) had received some laparoscopic exposure during residency; 29 (81%) had mobilized the colon, spleen or liver and 27 (75%) had dissected the renal vessels. Only 7 out of 33 respondents (21%) felt that their residency adequately prepared them to perform laparoscopy independently. There were no significant differences between the responses of the two cohorts. CONCLUSION: Most Canadian urology trainees are being exposed to laparoscopy, but more exposure is required in order to perform laparoscopy in practice. Many residents still require fellowship training to become facile in laparoscopy.

Should surgeons control fluoroscopy during urology procedures?

INTRODUCTION: Our study explored the impact of switching from surgeon- to radiation technologist (RT)-controlled fluoroscopy on fluoroscopy and operative times. We also identified factors impacting fluoroscopy and operative times for ureteroscopy (URS) with laser lithotripsy. METHODS: Patients undergoing urological procedures requiring fluoroscopy six months before and after the change from surgeon- to RT-controlled fluoroscopy were identified. Median fluoroscopy and operative times were compared between cohorts. Subgroup analyses were performed based on procedure performed. A multivariate analysis identified factors associated with increased fluoroscopy and operative times for URS with laser lithotripsy. RESULTS: Overall, no difference was found between surgeon and RT cohorts for fluoroscopy (58.0 vs. 56.7 seconds; p=0.34) or operative times (39 vs. 36 minutes; p=0.14). For URS with laser lithotripsy, fluoroscopy and operative times were longer in the surgeon-controlled cohort (76.0 vs. 54.0 seconds; p<0.01 and 48 vs. 40 minutes; p<0.01, respectively). For URS only, fluoroscopy time was decreased in the surgeon-controlled cohort (47.0 vs. 73.0 seconds; p=0.01). For URS with laser lithotripsy, factors independently associated with increased fluoroscopy time were male sex, flexible URS, glidewire use, and difficult ureteric stent insertion (p<0.05). Flexible ureteroscopy, glidewire use, previous ureteric stent placement, and difficult ureteric stent insertion were independently associated with increased operative time (p<0.05). CONCLUSIONS: Fluoroscopy and operative times are not significantly influenced by who controls fluoroscopy during urologic procedures. Patients undergoing URS with laser lithotripsy have decreased fluoroscopy and operative times with RT-controlled fluoroscopy. Patients undergoing URS only have decreased fluoroscopy times with surgeon-controlled fluoroscopy.

Comparison of Peditrol irrigation device and common methods of irrigation.

BACKGROUND AND PURPOSE: The Peditrol is a novel hands-free irrigation device that delivers a bolus of irrigant through the ureteroscope when the foot pedal is deployed. The purpose of this study was to compare the flow and pressures created by the Peditrol with those of commonly used methods of irrigation. MATERIALS AND METHODS: Flows through a flexible 6.9F Olympus ureteroscope (F-URS) and a 7.5F semirigid ACMI ureteroscope (S-URS) were measured in duplicate with the working channel empty and with a 2.2F Nitinol basket or a laser fiber in the working port. Irrigant flow was pressurized by gravity drainage at 100 cm H(2)O (GI), pressurized irrigant bag at 300 cm H(2)O (PI), handheld 60-cc syringe (HS), and the Peditrol. A 20-gauge angiocatheter was placed through the parenchyma into the renal pelvis of an ex-vivo cadaveric porcine kidney and attached to a pressure transducer. Pressures were measured in triplicate using the same irrigation techniques. RESULTS: With a basket or 200-microm laser fiber in the working port of the F-URS, Peditrol mean flows were superior to those of PI (3.3 and 6.3 times, respectively; P < 0.001) but similar to those of HS (0.7 to 1.1 times). All irrigation types resulted in intrarenal pressures greater than gravity irrigation (P < 0.05). The Peditrol demonstrated intrapelvic pressures <40 cm H(2)O when used with a 12/14F ureteral access sheath (AS). Without an AS, the intrapelvic pressure reached 92 cm H(2)O, similar to the pressures reached with the S-URS under various irrigation conditions (84-287 cm H(2)O) and comparable to the HS method through the F-URS (97 cm H(2)O). CONCLUSIONS: The Peditrol irrigation device generates superior flow through an F-URS compared with GI or PI, particularly with an instrument in the working port. Intrarenal pressures when used with an F-URS and AS are low. When an AS is not used, the intrarenal pressure is similar to or lower than pressures obtained using an S-URS with different irrigation modalities.

Semirigid ureteroscopy of the proximal ureter can be aided by external lower-abdominal pressure.

BACKGROUND AND PURPOSE: Smaller semirigid ureteroscopes with large working channels and excellent optics are widely available. Ureteroscopic treatment of upper-ureteral stones has become increasingly popular, although flexible ureteroscopy is more frequently the method of choice. Access to the upper ureter with a semirigid ureteroscope (SR-URS) can be challenging and hazardous, especially when negotiating the iliac vessels. We sought to determine whether lower-abdominal pressure (LAP) facilitated SR-URS access to the upper ureter for safe laser lithotripsy. PATIENTS AND METHODS: Thirty-two consecutive patients who underwent ureteroscopic management of upper- ureteral stones were evaluated. Twenty-four (75%) were male; seventeen (53%) had a right-sided stone. The mean largest stone diameter was 10.2 +/- 4.6 mm. These 32 patients were compared with a matched cohort of patients who underwent SR-URS procedures without the use of LAP. RESULTS: Access to the upper ureter was possible in 30 patients (94%). The LAP was helpful in 18 patients (56%): it facilitated passage of the SR-URS in 16 patients (50%) and laser fiber placement in 11 cases (34%). Access to the upper ureter was possible in all women. The mean operative time was 54 minutes in the LAP group and 75 minutes in the matched cohort without LAP (P = 0.026). There were no significant deformities of the SR-URS and no complications. CONCLUSIONS: Contrary to popular practice, the upper ureter can be accessed safely and efficiently with a 7.5F SR-URS in nearly all patients. Lower-abdominal pressure can be helpful to negotiate passage of the endoscope over the iliac vessels or to place the laser fiber on stones.

Laparoscopic simple prostatectomy.

Classically, surgical options for very large prostate glands, not amenable to transurethral resection, include suprapubic or retropubic simple prostatectomy and Holmium laser enucleation of the prostate (HoLEP). We present a case managed with a laparoscopic simple prostatectomy. Technical considerations are discussed as well as possible advantages of this approach including decreased blood loss, faster patient recovery and improved visualization.

Inadvertent transmission of polycystic kidney disease in kidney transplantation.

BACKGROUND: Although organ donors are rigorously tested, occasionally an unidentified donor disease can be transmitted to the recipient. These conditions include malignancies, infections, and, rarely, congenital diseases. CASE REPORT: We report a case of an inadvertent transmission of polycystic kidney disease from a 40-year-old trauma victim to both kidney recipients. There was no family history of renal disease in the donor. The renal allografts gradually increased in size with the development of cysts and functioned for 10 and 14 years. CONCLUSIONS: We report a case of inadvertent transmission of polycystic kidney disease from an unsuspecting deceased donor to both the recipients through renal allograft. Both the grafts lasted long enough to suggest that polycystic kidneys from deceased donors can be considered for transplantation.

Incidentally detected nephrogenic rests in the setting of congenital obstructive uropathy.

PURPOSE: Nephrogenic rests (NR) are clusters of cells similar to renal blastema. NR are frequently seen in kidneys with Wilms' tumor (WT) and are seen with higher frequency in nephrectomy specimens from obstructed and/or multicystic dysplastic kidneys (MCDK) compared to autopsy series of normal kidneys. The significance of NR and their role in tumorigenesis is largely unknown. We report the findings of two cases with NR associated with ureteral ectopy/obstruction and review the relevant literature. MATERIALS AND METHODS: Two cases of upper pole heminephrectomy associated with ectopic upper pole ureter and resultant hydronephrosis were found to have nephrogenic rests present on pathologic examination. A literature search was done to review recent developments in the understanding of NR and their significance, primarily to guide patient recommendations regarding follow-up. RESULTS: Recent developments in the understanding of NR include the description of intralobar versus perilobar nephrogenic rests and prognostic considerations associated with each. However, the implications of finding nephrogenic rests in upper pole hemi-nephrectomy specimens associated with ureteral ectopy is not well delineated. CONCLUSIONS: The role of NR in tumorigenesis is still poorly understood. Because of the still undefined relationship with WT we recommend patients with incidentally detected NR be followed with serial abdominal ultrasounds for the first 5 years of life.