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Background: The primary strategy for urinary diversion in radical cystectomy patients involves incorporation of autologous gastrointestinal conduits into the urinary tract which leads to deleterious consequences including chronic infections and metabolic abnormalities. This report investigates the efficacy of an acellular, tubular bi-layer silk fibroin (BLSF) graft to function as an alternative urinary conduit in a porcine model of urinary diversion.Materials and methods: Unilateral urinary diversion with stented BLSF conduits was executed in five adult female, Yucatan mini-swine over a 3 month period. Longitudinal imaging analyses including ultrasonography, retrograde ureteropyelography and video-endoscopy were carried out monthly. Histological, immunohistochemical (IHC), and histomorphometric assessments were performed on neoconduits at harvest.Results: All animals survived until scheduled euthanasia and displayed moderate hydronephrosis (Grades 1–3) in reconstructed collecting systems over the course of the study period. Stented BLSF constructs supported formation of vascularized, retroperitoneal tubes capable of facilitating external urinary drainage. By 3 months post-operative, neoconduits contained α-smooth muscle actin+ and SM22α+ smooth muscle as well as uroplakin 3A+ and pan-cytokeratin + urothelium. However, the degree of tissue regeneration in neotissues was significantly lower in comparison to ureteral controls as determined by histomorphometry. In addition, neoconduit stenting was necessary to prevent stomal occlusion.Conclusion: BLSF biomaterials represent emerging platforms for urinary conduit construction and may offer a functional replacement for conventional urinary diversion techniques following further optimization of mechanical properties and regenerative responses.

Introduction: Intestinal segments are currently used in reconstructive urology to create urinary diversion after cystectomy. Ileal conduit (IC) is the dominant type of urinary diversion. Nevertheless, IC is not an ideal solution as the procedure still requires entero-enterostomy to restore the bowel continuity. This step is a source of relevant complications that might prolong recovery time. Fabrication of artificial urinary conduit is a tempting idea to introduce an alternative form of urinary diversion which might improve cystectomy outcomes. Area covered: The aim of this review is to discuss available research data about artificial urinary conduit and identify major challenges for future studies. Expert opinion: Fabrication of artificial urinary conduit is in range of current tissue engineering technology but there are still many challenges to overcome. There is an urgent need for studies to be conducted on large animal models with long follow up to expose the limitation of experimental strategies and to gather data for translational research. [ABSTRACT FROM AUTHOR]

Background: The primary strategy for urinary diversion in radical cystectomy patients involves incorporation of autologous gastrointestinal conduits into the urinary tract which leads to deleterious consequences including chronic infections and metabolic abnormalities. This report investigates the efficacy of an acellular, tubular bi-layer silk fibroin (BLSF) graft to function as an alternative urinary conduit in a porcine model of urinary diversion. Materials and methods: Unilateral urinary diversion with stented BLSF conduits was executed in five adult female, Yucatan mini-swine over a 3 month period. Longitudinal imaging analyses including ultrasonography, retrograde ureteropyelography and video-endoscopy were carried out monthly. Histological, immunohistochemical (IHC), and histomorphometric assessments were performed on neoconduits at harvest. Results: All animals survived until scheduled euthanasia and displayed moderate hydronephrosis (Grades 1-3) in reconstructed collecting systems over the course of the study period. Stented BLSF constructs supported formation of vascularized, retroperitoneal tubes capable of facilitating external urinary drainage. By 3 months post-operative, neoconduits contained α -smooth muscle actin+ and SM22α+ smooth muscle as well as uroplakin 3A+ and pan-cytokeratin + urothelium. However, the degree of tissue regeneration in neotissues was significantly lower in comparison to ureteral controls as determined by histomorphometry. In addition, neoconduit stenting was necessary to prevent stomal occlusion. Conclusion: BLSF biomaterials represent emerging platforms for urinary conduit construction and may offer a functional replacement for conventional urinary diversion techniques following further optimization of mechanical properties and regenerative responses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Gundogdu, Nguyen, Hosseini Sharifi, Starek, Costa, Jones, Barham, Gelman, Clayman and Mauney.)

Abstract: Objective: The aim of this study is to estimate the overall rates of significant incontinent conduit-related complications and compare rates between conduit types. Methods: This was a retrospective review of 166 patients who underwent incontinent urinary diversion from April 1993 through April 2013. Patients were categorized by conduit type—ileal, sigmoid colon, and transverse colon. Significant conduit-related complications were assessed at 30 and 90days after surgery. Significant conduit-related complication was defined as any of the following: ureteral stricture, conduit leak, conduit obstruction, conduit ischemia, ureteral anastomotic leak, stent obstruction requiring intervention via interventional radiology procedure or reoperation, and renal failure. Results: A total of 166 patients underwent formation of an incontinent urinary conduit, most commonly during exenteration for gynecologic malignancy. There were 129 ileal, 11 transverse colon, and 26 sigmoid conduits. The overall significant conduit-related complication rate within 30days was 15.1%. Complication rates for ileal, transverse and sigmoid conduits were 14.7%, 0%, and 23.1%, respectively (Fisher's exact test, p =0.24). By 90days, the Kaplan–Meier estimated rates of significant complications were 21.8% overall, and 22.3%, 0%, and 28.9%, respectively, by conduit type (log-rank test, p =0.19). The most common significant conduit-related complications were conduit or ureteral anastomotic leaks and conduit obstructions. By 1 and 2years following surgery, the Kaplan–Meier estimated overall rate of significant conduit-related complication increased to 26.5% and 30.1%, respectively. Conclusions: Our study suggests that there are multiple appropriate tissue sites for use in incontinent conduit formation, and surgical approach should be individualized. Most significant conduit-related complications occur within 90days after surgery. [Copyright &y& Elsevier]

Placing of ileal conduit at the time of pelvic exenteration in combination with a same-side vertical rectus abdominis myocutaneous flap is controversial. We report our experience with the placement of the ileal conduit at the same side as the donor site of the vertical rectus abdominis myocutaneous flap in 12 patients and describe our technical approach. [ABSTRACT FROM AUTHOR]

Tissue engineering is focusing research effort on search for new biomaterials that might be applied to create artificial urinary conduit. Nevertheless, the demanding biomechanical characteristics necessary for proper conduit function is difficult to be replicated. In this study, we are introducing novel marine biomaterial obtained by decellularization of squid mantle derived from Loligo vulgaris. Squid mantles underwent decellularization according to developed dynamic flow two-staged procedure. Efficacy of the method was confirmed by computational dynamic flow analysis. Subsequently Decellularized Squid Mantle (DSM) underwent extensive histological analysis and mechanical evaluation. Based on gained biomechanical data the computational modelling using finite element method was utilized to simulate behavior of DSM used as a urinary conduit. Taking into account potential application in reconstructive urology, the DSM was then evaluated as a scaffold for urothelial and smooth muscle cells derived from porcine urinary bladder. Conducted analysis showed that DSM created favorable environment for cells growth. In addition, due to polarized structure and natural external polysaccharide layer, it protected seeded cells from urine. • Two-staged dynamic flow decellularization method was effective approach to obtain DSM. • Efficiency of decellularization method was confirmed with dynamic flow analysis. • DSM turned out to be suitable biomaterial for artificial urinary conduit. • Computational analysis was applied to evaluate DSM behavior as urinary conduit. • SMS and UC grew on DSM. [ABSTRACT FROM AUTHOR]

Urinary diversion after cystectomy has been a historical standard for the treatment of numerous benign and malignant diseases of the bladder. Since the first published description in the early 1900s, improvements in surgical technique and a better understanding of the metabolic sequelae postoperatively have greatly enhanced patient outcomes. Both continent and incontinent diversions are available to patients after cystectomy. In appropriately selected patients, orthotopic neobladder reconstruction can offer preservation of body image and continence, and continent cutaneous diversions represent a reasonable alternative. Conduit diversion, which remains the most commonly performed diversion technique, is ideal for patients who would benefit from a less morbid surgical procedure that negates the need for self-catheterization. This installment of the Core Curriculum in Nephrology outlines numerous aspects of urinary diversion, in which a multidisciplinary approach to postoperative management at the intersection of nephrology and urology is required to effectively optimize patient outcomes. This article includes a discussion of the various reconstructive options after cystectomy as well as a comprehensive review of frequently encountered short-term and long-term metabolic abnormalities associated with altered electrolyte and acid-base homeostasis., (Copyright © 2021 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

It has been known that urinary diversions juxtaposing the urinary and intestinal tracts lead to increased incidence of secondary malignancies. Although tumorigenesis in ureterosigmoidostomies follows the typical course from adenomas to adenocarcinomas, secondary malignancies arising from isolated intestinal diversions are much more heterogeneous. Research over the last half century has unveiled patterns of incidence and progression, while also uncovering possible mechanisms driving the neoplastic changes. In this review, we summarize the current understanding of these unique tumors, with the hope that the knowledge gained may shed light on the etiologies of other cancers arising from the urinary and intestinal tracts., (Copyright © 2017 Elsevier Inc. All rights reserved.)

This communication describes two patients in whom the appendix was used to extend the ureters to the skin surface for cutaneous diversion. The advantages and the disadvantages of the procedure are discussed and brief review of the literature is included. [ABSTRACT FROM AUTHOR]

Background: Prevention of surgical site infections (SSIs) can improve surgical quality through reductions in morbidity and cost. We sought to determine whether the abdominal closure protocol, in isolation, decreases SSI at an academic teaching hospital., Methods: Adult patients undergoing laparotomy were prospectively randomized to an abdominal closure protocol, which includes unused sterile instruments and equipment at fascial closure, or usual care. A 30-day SSI rates were compared. General surgery, colorectal, urology, or gynecologic oncology patients undergoing anticipated wound classification II cases were eligible., Results: Overall SSI rates were 11.6% in patients randomized to protocol closure vs 12.4% for usual care (total n = 233; P = .85). The abdominal closure protocol and usual care groups had similar rates of superficial (4.5% vs 4.1%; P = .9), deep (.9% vs 0%, P = .3), organ-space SSI rates (6.2% vs 8.3%, P = .55), and wound dehiscence (2.7% vs 5.3%; P = .24)., Conclusions: An abdominal closure protocol did not decrease the rate of SSI and is likely not a key intervention for SSI reduction., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Introduction: Incontinent urinary diversion using an ileal conduit is the most popular method used by urologists after bladder cystectomy resulting from muscle invasive bladder cancer. The use of gastrointestinal tissue is related to a series of complications with the necessity of surgical procedure extension which increases the time of surgery. Regenerative medicine together with tissue engineering techniques gives hope for artificial urinary conduit construction de novo without affecting the ileum., Material and Methods: In this review we analyzed history of urinary diversion together with current attempts in urinary conduit construction using tissue engineering methods. Based on literature and our own experience we presented future perspectives related to the artificial urinary conduit construction., Results: A small number of papers in the field of tissue engineered urinary conduit construction indicates that this topic requires more attention. Three main factors can be distinguished to resolve this topic: proper scaffold construction along with proper regeneration of both the urothelium and smooth muscle layers., Conclusions: Artificial urinary conduit has a great chance to become the first commercially available product in urology constructed by regenerative medicine methods.