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This study characterizes the degree of cure c, of a two-part epoxy/acrylic photopolymer used in stereolithography, SLA. The use of solid free form fabrication has added a whole new list of thermosets with a chemical reaction--curing reaction--targeted for these specific manufacturing processes. The studied thermosetting system exhibits a fast curing reaction triggered by a UV-light source. An innovative stepwise method to quantify the degree of cure using Raman spectroscopy is reported. This method abates the Raman noise and compensates for the weak signal of fast measurements. The Raman data processing algorithm BEADS was implemented. The technique presented here was capable of following the degree of cure of the individual components of the photopolymer. Based on the epoxy/acrylic monomers concentration (75%/25%), the degree of cure for the whole system was quantified. The experimental results were modeled using a modified phenomenological kinetics equation. This model includes the dependency of the rate of cure on the light intensity, and cure state. Based on the analysis reported here, the proposed model accurately fits the initiation, propagation, and termination phases of the cure cycle. The technique and methods presented here can potentially be integrated to in situ process monitoring with instant parameter feedback, and numerical modeling of residual stresses in additive manufacturing of thermosets., INTRODUCTION Photopolymers possess unique capabilities including ambient temperature curing and control over where and when the polymer cures. These capabilities have prompted a variety of products like dental materials, contact [...]

Introduction: Abdominal sacrocolpopexy provides effective longterm outcomes for apical pelvic organ prolapse. The introduction of robotic-assisted laparoscopic sacrocolpopexy (RALS) has mitigated the risks of abdominal surgery. This study aims to evaluate the preoperative patient characteristics, intraoperative surgical parameters, and postoperative outcomes of RALS, which has not been previously performed in Canada. Methods: A retrospective chart review of 47 patients who have undergone RALS from 2016-2018 by a single surgeon at a tertiary care hospital in Canada was completed. Results: This case series had a mean age of 60.2 years, body mass index (BMI) of 28.3 kg/m2, and Charlson comorbidity index of 2.0. Preoperatively, 13 (28%), 23 (49%), and 11 (23%) patients had Baden-Walker grade 2, 3, and 4 apical prolapse, respectively. Intraoperatively, 45 (96%) patients underwent concomitant procedures, including 36 (77%) with adnexal surgery, 32 (68%) with anti-incontinence surgery, and 25 (53%) with hysterectomy. Intraoperative complications included one ureteric injury, two bladder injuries, and three vaginotomies. The mean robotic console time, surgery time, and total operating room times were 125.6, 148.6, and 190.6 minutes, respectively. Postoperatively, data was analyzed for 32 (68%) patients with greater than 12 weeks' followup. There was no recurrence of apical prolapse on exam after a mean followup of 60.1 weeks. Seven (22%) patients experienced symptomatic prolapse in the posterior compartment. There were two grade 3 Clavien- Dindo complications, including osteomyelitis and mesh exposure. Conclusions: RALS can be safely and effectively performed with other pelvic procedures with good outcomes. Concurrent posterior repairs may be considered in select patients. [ABSTRACT FROM AUTHOR]

The sporicidal efficacies of the two fumigants, chlorine dioxide gas and vaporous hydrogen peroxide sterilant, on six building structural materials are studied. A high-throughput quantitative method is developed for determining the efficacies of fumigants and the spore recoveries from five porous materials and on nonporous material.

Introduction: Robotic-assisted simple prostatectomy (RASP) has been touted as an alternative to open simple prostatectomy (OSP) to treat large gland benign prostatic hyperplasia. Our study assesses our institution's experience with RASP and reviews the literature. Methods: We performed a retrospective chart review from January 2011 to November 2013 of all patients undergoing RASP and OSP. Operative and 90-day outcomes, including operation time, intraoperative blood loss, length of hospital stay (LOS), transfusion requirements, and complication rates, were assessed. Results: Thirty-two patients were identified: 4 undergoing RASP and 28 undergoing OSP. There was no difference in mean age at surgery (69.3 vs. 75.2 years; p = 0.17), mean Charlson Comorbidity Index (2.5 vs. 3.5; p = 0.19), and mean prostate volume on TRUS (239 vs. 180 mL; p = 0.09) in the robotic and open groups, respectively. There was a significant difference in the mean length of operation, with RASP exceeding OSP (161 vs. 79 min; p = 0.008). The mean intraoperative blood loss was significantly higher in the open group (835.7 vs. 218.8 mL; p = 0.0001). Mean LOS was shorter in the RASP group (2.3 vs. 5.5 days; p = 0.0001). No significant differences were noted in the 90-day transfusion rate (p = 0.13), or overall complication rate at 0% with RASP vs. 57.1% with OSP (p = 0.10). Conclusions: Our data suggest RASP has a shorter LOS and lower intraoperative volume of blood loss, with the disadvantage of a longer operating time, compared to OSP. It is a feasible technique and deserves further investigation and consideration at Canadian centres performing robotic prostatectomies. [ABSTRACT FROM AUTHOR]

Introduction: The Hemopatch® is a novel polyethylene glycol-coated (PEG-coated) collagen patch that acts as a topical hemostatic agent. It has been applied to a variety of surgical techniques. Here, we present our series and technique using a PEG-coated patch for minimally invasive partial nephrectomy (MIPN). Methods: We conducted a retrospective chart review of all patients undergoing MIPN by a single surgeon at a tertiary Canadian medical center between July and December 2018. We included patients if a PEG-coated patch was used to close the renal parenchymal defect. We also describe in detail our technique for laparoscopic patch deployment. Results: A total of 17 patients met inclusion criteria, of whom 12 were male. Mean age was 63 years old. Median size of renal mass was 2.85 cm in largest dimension and median RENAL score was 6. Hilar clamping was carried out in 12 (70.9%) cases, with an average warm ischemic time of 16.1 minutes. The remainder of cases were performed off-clamp. Median estimated blood loss was 238 mL and the mean change in hemoglobin on postoperative day 1 compared to preoperatively was 21.2 g/L. The average length of stay was 1.76 days. No patient required blood transfusion or underwent angioembolization or re-operation for bleeding within 90 days. There were no Clavien-Dindo grade 3 or greater complications. Conclusions: A PEG-coated patch can be used safely and effectively in lieu of traditional two-layer renorrhaphy with acceptable outcomes. Larger, prospective series are required to ascertain its true value and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Introduction: Partial nephrectomy remains the standard of care in early stage, organ-confined renal tumours. Recent evidence suggests that minimally invasive surgery can proceed without segmental vessel clamping. In this study, we review our experience at a Canadian centre with zero ischemia robotic-assisted partial nephrectomy (RAPN). Methods: A retrospective chart review of zero ischemia RAPN was performed. All surgeries were consecutive partial nephrectomies performed by the same surgeon at a tertiary care centre in Northern Alberta. The mean follow-up period was 28 months. These outcomes were compared against the current standards for zero ischemia (as outlined by the University of Southern California Institute of Urology [USC]). Results: We included 21 patients who underwent zero ischemia RAPN between January 2012 and June 2013. Baseline data were similar to contemporary studies. Twelve (57.1%) required no vascular clamping, 7 (33.3%) required clamping of a single segmental artery, and 2 (9.5%) required clamping of two segmental arteries. We achieved an average estimated blood loss of 158 cc, with a 9.2% average increase in creatinine postoperatively. Operating time and duration of hospital stay were short at 153 minutes and 2.2 days, respectively. Conclusion: Zero ischemia partial nephrectomy was a viable option at our institution with favourable results in terms of intra-operative blood loss and postoperative creatinine change compared to results from contemporary standard zero ischemia studies (USC). To our knowledge, this is the first study to review an initial experience with the zero ischemia protocol in robotic-assisted partial nephrectomies at a Canadian hospital. [ABSTRACT FROM AUTHOR]

Introduction: Partial nephrectomy remains the gold standard in the management of small renal masses. However, minimally invasive partial nephrectomy (MIPN) is associated with a steep learning curve, and optimal, standardized techniques for time-efficient hemostasis are poorly described. Given the relative lack of evidence, the goal was to describe a set of actionable guiding principles, through an expert working panel, for urologists to approach hemostasis without compromising warm ischemia or oncological outcomes., Methods: A three-step modified Delphi method was used to achieve expert agreement on the best practices for hemostasis in MIPN. Panelists were recruited from the Canadian Update on Surgical Procedures (CUSP) Urology Group, which represent all provinces, academic and community practices, and fellowship-and non-fellowship-trained surgeons. Thirty-two (round 1) and 46 (round 2) panellists participated in survey questionnaires, and 22 attended the in-person consensus meeting., Results: An initial literature search of 945 articles (230 abstracts) underwent screening and yielded 24 preliminary techniques. Through sequential survey assessment and in-person discussion, a total of 11 strategies were approved. These are temporally distributed prior to tumor resection (five principles), during tumor resection (two principles), and during renorrhaphy (four principles)., Conclusions: Given the variability in tumor size, depth, location, and vascularity, coupled with limitations of laparoscopic equipment, achieving consistent hemostasis in MIPN may be challenging. Despite over two decades of MIPN experience, limited evidence exists to guide clinicians. Through a three-step Delphi method and rigorous iterative review with a panel of experts, we ascertained a guiding checklist of principles for newly beginning and practicing urologists to reference.

Introduction: Abdominal sacrocolpopexy provides effective long-term outcomes for apical pelvic organ prolapse. The introduction of robotic-assisted laparoscopic sacrocolpopexy (RALS) has mitigated the risks of abdominal surgery. This study aims to evaluate the preoperative patient characteristics, intraoperative surgical parameters, and postoperative outcomes of RALS, which has not been previously performed in Canada., Methods: A retrospective chart review of 47 patients who have undergone RALS from 2016-2018 by a single surgeon at a tertiary care hospital in Canada was completed., Results: This case series had a mean age of 60.2 years, body mass index (BMI) of 28.3 kg/m 2 , and Charlson comorbidity index of 2.0. Preoperatively, 13 (28%), 23 (49%), and 11 (23%) patients had Baden-Walker grade 2, 3, and 4 apical prolapse, respectively. Intraoperatively, 45 (96%) patients underwent concomitant procedures, including 36 (77%) with adnexal surgery, 32 (68%) with anti-incontinence surgery, and 25 (53%) with hysterectomy. Intraoperative complications included one ureteric injury, two bladder injuries, and three vaginotomies. The mean robotic console time, surgery time, and total operating room times were 125.6, 148.6, and 190.6 minutes, respectively. Postoperatively, data was analyzed for 32 (68%) patients with greater than 12 weeks' followup. There was no recurrence of apical prolapse on exam after a mean followup of 60.1 weeks. Seven (22%) patients experienced symptomatic prolapse in the posterior compartment. There were two grade 3 Clavien-Dindo complications, including osteomyelitis and mesh exposure., Conclusions: RALS can be safely and effectively performed with other pelvic procedures with good outcomes. Concurrent posterior repairs may be considered in select patients.

Introduction: Total intra-corporeal robot-assisted radical cystectomy (RARC) with total intracorporeal neobladder formation is relatively new in the treatment of bladder cancer. We present our experience and believe it is the first Canadian reported series with this technique., Methods: This is a case series of 4 patients, who underwent total RARC, pelvic lymphadenectomy and creation of an intra-corporeal ileal neobladder. Surgical technique is described and perioperative variables, pathologic data, and complication rates are reported., Results: The mean patient age was 61.8 and the mean body mass index was 27.01 kg/m(2). The mean operative time, estimated blood loss, time to full diet and length of stay were 522.8 minutes (standard deviation [SD] 74.5), 237.5 mL (SD 47.9), 9 days (range: 3-24) and 12.8 days (range: 6-31), respectively. All patients completed postoperative functional evaluation showing a mean neobladder capacity of 575 cc (range: 500-720). Surgical margins and pathological nodal status were negative in all patients with no evidence of disease recurrence or progression on follow-up. Three of the 4 patients suffered a complication within 90 days, with one occurring later in the first year. All early complications were Clavien grade I-II (grade I [n = 1]; grade II [n = 2]) and the later complication was grade IIIa. The mean follow-up was 632 days (range: 562-730). The limitation of our study is its small sample size with highly selected patients to compensate for the learning experience. The follow-up is short; however, the outcomes are comparable to early experiences reported at other institutions., Conclusions: In our initial experience, RARC with total intracorporeal neobladder formation is safe. We expect that with experience the expense of robotic surgery can be compensated with early ambulation and shorter stay.