Feasibility Study of Vascularized Composite Urinary Bladder Allograft Transplantation in a Cadaver Model.

PURPOSE: The purpose of this study was to establish the feasibility of performing a urinary bladder vascularized composite allograft transplantation for either bladder augmentation or neobladder creation. MATERIALS AND METHODS: Six adult cadavers were studied. Cadavers were excluded for any previous pelvic surgery, radiation, vascular surgery or history of pelvic malignancy. An intravascular colored silicone and barium mixture was injected and both computerized tomography scans and gross dissections were performed. Contrast enhanced computerized tomography imaging was used to delineate urinary bladder vascular anatomy variability. Bladders were explanted en bloc from 2 cadavers with bilateral vascular pedicles based on the external iliac vessels and "transplanted" to replicate a bladder transplant. RESULTS: Contrast enhanced 3-D-computerized tomography reconstructions and cadaver dissections revealed distal vascular variability with proximal blood supply based primarily on the internal iliac artery. Urinary bladder vascularized composite allograft transplantation was successfully performed during 2 mock transplants with the vascular anastomosis done to the recipient external iliac artery and vein. CONCLUSIONS: Urinary bladder vascularized composite allograft transplantation is technically and anatomically feasible. This procedure may obviate the use of intestinal segments for bladder reconstruction in select patients. A phase 1 clinical trial is in progress.

A new heterotropic vascularized model of total urinary bladder transplantation in a rat model.

This study developed a new procedure of urinary bladder transplantation on a rat model (n = 40). Heterotopic urinary bladder transplantation (n = 10) in the right groin vessels was performed. Direct urinary bladder examination, microangiography, histological analysis, and India ink injection were performed to evaluate the proposed method's functionality. Observation time was four weeks. One week after the procedure, the graft survival rate was 80%, two urinary bladders were lost due to anastomosis failure. The rest of the grafts survived two weeks without any complications. Lack of transitional epithelium or smooth muscle layer loss and lack of inflammatory process development were observed. This study was performed in order to obtain the necessary knowledge about urinary bladder transplantation. The proposed technique offers a new approach to the existing orthotropic models.

Pelvic peritoneum reconstruction using the bladder peritoneum flap in laparoscopic extralevator abdominoperineal excision: A multi-center, prospective single-arm cohort study (IDEAL Phase 2A).

INTRODUCTION: Extralevator abdominoperineal excision (ELAPE) may cause various surgical complications including disruption of perineal wound, perineal hernia and adhesive small-bowel obstruction. Pelvic peritoneum reconstruction (PPR) could prevent those complications, but it may not always be achievable, especially in patients with severe pelvic fibrosis after neoadjuvant radiotherapy. Our previous study has reported the application of the PPR using the bladder peritoneum flap in laparoscopic ELAPE. The aim of the study is to evaluate the short-term clinical, technical and safety outcomes of PPR using the bladder peritoneum flap in laparoscopic ELAPE. METHODS AND ANALYSIS: This is a multi-center prospective single-arm cohort study and fulfill the IDEAL 2A stage principle. Rectal cancer patients undergoing laparoscopic ELAPE, suffering rigid pelvis or huge perineal peritoneum defect, and having difficulty in primary perineal wound closure will be considered eligible. Main exclusion criteria are being complicated with urgent complications, ASA grade >3 and accompanied with mental illness. After informed consent, 30 patients are planned to be included in the study. Standard laparoscopic ELAPE with pelvic peritoneal floor reconstruction using bladder peritoneum flap are to be performed. The surgical safety is to be evaluated after one-year follow-up. Primary endpoints are the occurrence of intraoperative and postoperative complications of PPR using the bladder peritoneum flap. Second endpoints are overall complication rate within 30 days after surgery, extent of small intestine falling down to pelvic cavity, and other follow-up consequences within 1 year after surgery. ETHICS AND DISSEMINATION: This experiment was approved by the Biomedical Ethics Committee of West China Hospital of Sichuan University. TRIAL REGISTRATION: NCT04177407.

In-vivo regeneration of bladder muscular wall with whole decellularized bladder matrix: A novel hourglass technique for duplication of bladder volume in rabbit model.

OBJECTIVE: To determine histological aspects of decellularized bladder graft to achieve a double-sized bladder by novel hourglass technique; using rabbit models. METHODS: Sixteen rabbit bladders were decellularized and underwent laboratory investigations. After making a laparotomy incision and exposure of bladders in another 16 rabbits (partial detrusor myomectomy), they were separated into two groups. The fundus of the decellularized scaffold was anastomosed to the fundus of the native bladder via the serosal layer, and the omentum and a double-J stent were placed in the decellularized bladder by no direct contact with the urine (Group A, n=8). In group B (n=8), the bladder was augmented applying the decellularized bladder that was in contact with the urine. After 6 months, the omentum was brought out of the neck of the engineered bladder and the anastomosis was opened. Biopsies were taken at 1, 3, and 9 months postoperatively. RESULTS: Cell removal with preservation of extracellular matrix structure was confirmed in decellularized bladders. Histological examination after 1 month demonstrated few cells at the border of the grafts. After 3 months, the region of the graft was indistinguishable from the natural bladder with continuity of transitional epithelium of natural bladder on the decellularized grafted scaffolds. The organization of muscle layers was similar to native bladder muscle layers after 9 months. IHC staining markers were highly expressed after 9 months. Interestingly, bladders had a high fibrosis grade in group B compared with hourglass technique. CONCLUSION: We confirmed that decellularized bladder may be a reliable scaffold and viable material for bladder augmentation.

Use of pediatric donor en bloc kidneys along with bladder segment in pediatric liver-kidney and multivisceral-kidney transplantation.

The combination of pediatric multivisceral and kidney transplantation leads to additional recipient risks due to the number of anastomoses and to the small sizes of donor structures. The inclusion of donor kidneys, ureters, and a bladder patch en bloc with multivisceral organs decreases the number and complexity of anastomoses and has not yet been reported. Four patients were transplanted in this fashion; three underwent multivisceral-kidney and one underwent liver-kidney transplantation. The first patient was a 3-year-old male with polycystic kidney disease and congenital hepatic fibrosis. The second was a 7-year-old female with complications from necrotizing enterocolitis. The third was a 12-month-old male with megacystis microcolon intestinal hypoperistalsis syndrome and secondary hydronephrosis, and the fourth was a 3-year-old male with multiple intestinal resections secondary to incarcerated hernia. The third patient developed a right ureteral stenosis with an intact bladder patch. The fourth child expired from maintained abdominal sepsis. The first 3 patients maintained normal graft function. There were no cases of thrombosis, arterial stenosis, or urinary leakages. These reported cases demonstrate that small pediatric en bloc transplantation of the multivisceral organs and dual kidneys with a bladder patch anastomosis is a feasible and less complex alternative to the standard procedure.

Large Hiatal Hernia Repair with Urinary Bladder Matrix Graft Reinforcement and Concomitant Sleeve Gastrectomy.

BACKGROUND: There is no current consensus on the management of large hiatal hernias concomitant with performance of a sleeve gastrectomy procedure. Proposed solutions have included performing a modified Nissen fundoplication, performing cruroplasty alone, utilizing the Linx device, performing cruroplasty with reinforcement material, and avoiding the sleeve procedure altogether in favor of a bypass procedure in order to minimize gastroesophageal reflux. Urinary bladder matrix (UBM) represents a biologically derived material for use in hiatal hernia repair reinforcement with the potential to improve durability of repair without incurring the risks of other reinforcement materials. METHODS: This study reports the results of a retrospective chart review of 32 cases of large hiatal hernia repair utilizing both primary crural repair and UBM reinforcement concomitant with laparoscopic sleeve gastrectomy by a single surgeon. Hernia diameter averaged 6 cm (range 4-9 cm). After an average of 1 year followup, 30 patients were assessed for subjective symptoms of gastroesophageal reflux (GERD) using the Gastroesophageal Reflux Disease-Health Related Quality of Life (GERD-HRQL) score. Twenty patients were evaluated with either upper gastrointestinal (GI) series, endoscopy, or both. RESULTS: Each repair was successful and completed laparoscopically concomitant with sleeve gastrectomy. Anterior and posterior cruroplasty was performed using interrupted 0-Ethibond suture using the Endostitch device. The UBM graft exhibited favorable handling characteristics placed as a keyhole geometry sutured to the crura with absorbable suture. A careful chart review was undertaken to assess for complications. There have been no reoperations. After a median of 12 months (range, 4-27 months) of followup, an assessment of recurrences or long-term complications was completed. Median GERD-HRQL score was 6, with a range of 0 to 64 (of possible 75), indicating very low-level reflux symptomatology. Follow-up upper GI radiographs or endoscopy were obtained in 20 cases and show intact repairs. CONCLUSION: In this series of 32 cases, laparoscopic cruroplasty with UBM graft reinforcement has been effective and durable at 12 months of followup. This technique may offer one satisfactory solution for large hiatal hernia repair concomitant with laparoscopic sleeve gastrectomy that may achieve a durable repair with low GERD symptoms.

Managing Ulcers Associated with Pyoderma Gangrenosum with a Urinary Bladder Matrix and Negative-Pressure Wound Therapy.

Pyoderma gangrenosum (PG) is a rare disease that presents as painful ulcerations with inflammation and undermining at the borders. The ulcers can occur anywhere on the body but are most commonly seen on the lower extremities. The etiology of PG is unknown, and there are no definitive diagnostic criteria; PG is a diagnosis of exclusion, which can present serious delays in treatment.Patients should be treated with an interdisciplinary approach with aggressive immunosuppression, treatment of any comorbidities, maximization of nutrition status, reconstructive surgery for treatment of the wound, and physical therapy for deconditioning.This article presents a case study of one patient treated with a porcine urinary bladder matrix and negative-pressure wound therapy; this treatment combination provided pain relief, coverage of the wound, an acceptable aesthetic outcome, and long-term stability.

Effects of topical applications of porcine acellular urinary bladder matrix and Centella asiatica extract on oral wound healing in a rat model.

OBJECTIVES: To evaluate the effects of topical applications of porcine acellular urinary bladder matrix (AUBM) and Centella asiatica extract (CAE) on the healing of tongue wounds in a rat model. MATERIALS AND METHODS: Wounds were made in the tongue using a punch tool in 64 male Sprague-Dawley rats, randomized into four groups (n = 16 per group): group 1 (control), group 2 (CAE), group 3 (AUBM mixed with orabase), and group 4 (orabase). No product was applied in group 1 and groups 2-4 received three daily topical applications. The animals were weighed on day 0 and at the time of euthanasia. Four rats in each group were euthanized at days 2, 7, 14, and 21 and the tongues were processed for: macroscopic morphometric analysis, myeloperoxidase (MPO) and malondialdehyde (MDA) levels, histological wound repair (degree of reepithelialization and inflammation), and CD31 positivity. RESULTS: The animals' weight gain, histological wound repair, and CD31 positivity from greatest to least were: AUBM > CAE > orabase > control. Percentage of tongue occupied by wound, MPO, and MPA levels from least to greatest were: AUBM < CAE < orabase < control, whereby the AUBM group showed significant differences (p ≤ 0.05) in comparison with the other groups on days 2, 7, 14, and 21 for percentage of tongue occupied by wound and MDA and on days 7, 14, and 21 for MPO. CONCLUSIONS: CAE is effective for oral tissue regeneration, while AUBM is an even more potent means of oral mucosa regeneration. CLINICAL RELEVANCE: AUBM may be beneficial to patients with oral wounds; this finding requires further clinical and laboratory investigation.

Symptomatic, Radiological, and Quality of Life Outcome of Paraesophageal Hernia Repair With Urinary Bladder Extracellular Surgical Matrix: Comparison With Primary Repair.

INTRODUCTION: Paraesophageal hernia repairs are prone to recurrence and mesh reinforcement is common. Both biologic and prosthetic meshes have been used. We report a comparison of a new type of biologically derived graft, Gentrix Surgical Urinary Bladder Matrix (UBM). METHODS: The medical records of 65 patients who underwent paraesophageal hernia repair (PEHR) were reviewed. Primary data points included demographics, first-time or recurrent hernia, operative approach, graft or primary repair, operative time, and postoperative complications. Patients then underwent upper gastrointestinal series, completed the GERD-HRQL symptom severity questionnaire, and the SF-36 generic quality of life instrument. RESULTS: A total of 32 patients underwent graft-reinforced repair, 33 underwent primary repair. More patients in the UBM group were being treated for recurrent PEH. Demographic data and postoperative complications were similar. There was no difference in recurrence rates, size of recurrence, postoperative symptomatic or quality of life improvement. Patients who suffered recurrence in the primary repair group had more severe symptoms and a higher rate of dissatisfaction. Of the 3 patients with recurrences after Gentrix placement, reoperation demonstrated anterior failure where no reinforcement had occurred because of the posteriorly placed U-shaped graft. CONCLUSIONS: The use of UBM was not associated with an increased complications despite use in more difficult patients. Although there appeared to be no difference in recurrence rate or size, it was associated with less severe symptomatic recurrences. The U-shape configuration is prone to recurrence at the site of the repair not covered by the graft, suggesting that a keyhole configuration may be superior.

Expression patterns of mesenchymal stem cell-specific proteins in adipose tissue-derived cells: possible immunosuppressing agent in partial allograft for restoring the urinary bladder in rabbits / Padrão de expressão de proteínas específicas das células-tronco mesenquimais derivadas de tecido adiposo: possível agente imunossupressor em aloenxerto parcial para restauração de vesícula urinária de coelhos

Adipose tissue-derived stem cells (ADSCs) are an attractive source of mesenchymal stem cells (MSCs) for use in tissue engineering and clinical applications. This paper focuses on the characterization of ADSCs used as immunosuppressive agent in rabbits undergoing partial allograft for urine bladder restorage. For this study highlighted the characterization of the ADSCs used as immunosuppressive agents in rabbits submitted to partial allograft for restoration of the urinary vesicle, using 25 animals, six months old, New Zealand. ADSCs at the third peal were characterized by the MSC-specific CD105, CD73 and CD90 expression and by the absence of the hematopoietic marker CD45, as revealed by flow cytometry analysis. Moreover, ADSCs were efficient in preventing allograft rejection from the urinary bladder, as judged by biochemical, clinical and ultrasonography analysis. Together, these results compose characterization of protein expression profiles and immunosuppressive functionality of ADSCs in rabbits, which had undergone partial allografts of the urinary bladder, foreseeing future applications in clinical practice.(AU)

As células mesenquimais derivadas de tecido adiposo (ADSCs) são uma fonte atraente de células-tronco mesenquimais (MSCs) para uso na engenharia de tecidos e suas aplicações clínicas. Este trabalho destacou a caracterização das ADSCs utilizadas como agentes imunossupressores em coelhos submetidos a aloenxerto parcial para restauração da vesícula urinária, sendo utilizados 25 animais, de seis meses de idade, Nova Zelândia. As ADSCs, após o terceiro repique, foram caracterizadas pela expressão específica de MSC CD105, CD73 e CD90 e pela ausência do marcador hematopoiético CD45, tal como revelado por análise de citometria de fluxo. Além disso, os ADSCs foram eficientes na prevenção da rejeição de aloenxertos da vesícula urinária, conforme avaliado por análises clínica, bioquímica e ultrassonográfica. Juntos, esses resultados compõem a caracterização dos perfis de expressão proteica e a funcionalidade imunossupressora de ADSCs em coelhos, que sofreram aloenxertos parciais da bexiga, prevendo futuras aplicações na prática clínica.(AU)

Long-term clinical, radiological, and histological follow-up after complex ventral incisional hernia repair using urinary bladder matrix graft reinforcement: a retrospective cohort study.

BACKGROUND: Complex ventral incisional hernia repair represents a challenging clinical condition in which biologically derived graft reinforcement is often utilized, but little long-term data inform that decision. Urinary bladder matrix (UBM) has shown effectiveness in diverse clinical settings as durable reinforcement graft material, but it has not been studied over a long term in ventral incisional hernia repair. This study evaluates the clinical, radiographic, and histological outcome of complex incisional hernia repair using UBM reinforcement with 12-70 months of follow-up. METHODS: A single-arm, retrospective observational study of all ventral incisional hernia repairs utilizing UBM reinforcement over a 6-year time frame by a single surgeon was performed. Patients were assessed in long-term follow-up clinically and with the Carolina Comfort Scale. A subset of patients was assessed with abdominal wall ultrasound or CT scan. Three patients had abdominal wall fascial biopsies years after the incisional hernia repair with UBM graft, and the histology is analyzed. RESULTS: 64 patients underwent repair of complex incisional hernias with UBM graft reinforcement by a single surgeon. 42 patients had concomitant procedures including large or small bowel resection, excision of infected mesh, evacuation of abscess or hematoma, cholecystectomy, or panniculectomy with abdominoplasty. 16 patients had ostomies at the time of repair. Median follow-up time is 36 months, with a range of 12-70 months. Nine patients (14%) have required surgical repair of a recurrent hernia, and a tenth patient has a recurrence that is managed non-surgically, for a total recurrence rate of 15.6% over the entire time frame. Median time to recurrence was 32 months, and a Kaplan-Meier freedom from recurrence curve is depicted. 28 patients have undergone ultrasound or CT assessments of the abdominal wall which demonstrate radiographic fascial integrity 12-70 months after repair. Three patients have been re-explored for unrelated reasons in the years following ventral incisional hernia repair with UBM, and full thickness fascial biopsies demonstrate a robust remodeling response histologically similar to native myofascial tissue. No patients have developed graft infection, fistulization to the graft, or required graft explantation. Carolina Comfort Scale assessment of 45 patients 3 years after the repair averaged 16 out of a possible 115. CONCLUSION: In 64 patients undergoing complex ventral incisional hernia repair with UBM reinforcement, all have experienced successful resolution of complex clinical conditions and 15.6% of these repairs have recurred at a median follow-up of 3 years. Three full-thickness biopsies of the repaired fascia years later shed light on a promising remodeling response which may signal strength and durability comparable to native fascia.

Acellular Fish Skin Grafts and Pig Urinary Bladder Matrix Assessed in the Collagen-Induced Arthritis Mouse Model.

It is vital that cellular- and tissue-based products (CTPs) used for wound treatment do not provoke autoimmunity. In this study, the immunogenic response to extracts of 2 CTPs of piscine and porcine origin was assessed in the collagen-induced arthritis model. Male DBA/1J mice were divided into 4 groups, each composed of 7 to 9 animals. Each animal was injected with one of following to assess their immune responses: (1) bovine type II collagen (100 µg) in Freund's adjuvant, (2) extract of piscine skin (100 µg) in Freund's adjuvant, (3) extract of porcine urinary bladder matrix (100 µg) in Freund's adjuvant, or (4) Freund's adjuvant alone (control) at the beginning of the experiment and 3 weeks later. Clinical signs of arthritis were assessed from week 5 onwards, and anti-type II and anti-type I collagen antibody immunoglobulin G (IgG) serum levels were measured before injections and 8 weeks after exposure using enzyme-linked immunosorbent assays. Only the mice exposed to bovine type II collagen developed clinical arthritis accompanied by very high anti-type II collagen IgG serum levels. Anti-type II collagen IgG serum levels were also detected in the porcine group but were undetectable in the piscine skin and control groups after 8 weeks. There were no significant differences in anti-type I collagen IgG serum levels among the groups. The results showed that piscine skin did not provoke systemic autoimmunity against type II collagens in DBA/1J mice.

Paraesophageal Hiatal Hernia Repair With Urinary Bladder Matrix Graft.

BACKGROUND AND OBJECTIVES: Paraesophageal hiatal hernia repair can be performed with or without mesh reinforcement. The use, technique, and mesh type remain controversial because of mixed reports on mesh-related complications. Short-term outcomes have become important in all forms of surgery. METHODS: From January 2012 through April 2017, all patients who underwent isolated hiatal hernia repair in our center were reviewed. Concomitant bariatric surgery cases were excluded. Repairs reinforced by porcine urinary bladder matrix (UBM) graft were compared to non-UBM repairs. Statistical comparison was based on a Wilcoxon 2-sample test or Fisher's exact test. RESULTS: We reviewed 239 charts; 110 bariatric cases and 8 cases with non-UBM reinforcement were excluded. We identified 121 patients: 56 UBM-reinforced (46.3%) versus 65 non-UBM (53.7%). Sixteen (28.6%) UBM cases were male versus 23 (35.4%) non-UBM cases. The UBM patients were significantly older (63.9 versus 54.3; P = .001). There was no difference in mean BMI (29.6 vs 28.5; P = .28). Cases were performed laparoscopically (60.7% vs 67.7%; P = .45) or robotically (39.3% vs 32.3%; P = .45), with no conversions to open. The UBM group had a longer mean operative time (183 minutes vs 139 minutes; P = .001).There was no difference in median length of stay (2 days vs 2 days; P = .09) or 30-day readmission rate (7.1% vs 7.5%; P =.99). Postoperative complications were graded according to the Clavien-Dindo classification, and there was no difference (19.6% vs 9.2%; P = .12). CONCLUSIONS: Hiatal hernia repair with UBM reinforcement can be performed safely with no increase in postoperative complications.

Bladder Mucosal Graft Vaginoplasty: A Case Report.

BACKGROUND: Female vaginoplasty reconstruction, by choice, is usually performed with adjacent tissue. However in some clinical conditions such as high urogenital confluence sinus, cloacal malformation with extreme vaginal hypoplasia, local tissue may not be available. When vaginal replacement is performed in pediatric patients intestinal segments is preferred to non-operative procedures that require continuative dilations. However mucus production, malignant transformation risk and diversion colitis are important side effects. TECHNIQUE: We present a nouvel technique for vaginoplasty in a female child presenting with an isolated urogenital sinus malformation without virilization. The patient at 20 months underwent vaginoplasty using tubularized bladder mucosal graft. RESULTS: Surgical procedure was devoid of complications. Pubertal development occurred at age of 15. She underwent regular follow up until 18 years of age. At this age we performed clinical evaluation: absence of vaginal introitus stenosis and good cosmetic results were observed. Then she underwent vaginoscopy with multiple biopsies. Pathology examination of the bladder mucosal graft evidenced a normal structure of the mucosa, with a stratified squamous epithelium. DISCUSSION: Different techniques are taken into account for vaginal reconstruction according to the severity and to the type of malformation. We describe the use of bladder mucosal graft with favorable results after long term follow-up.

Oral Cavity Reconstruction Outcomes Using a Porcine Urinary Bladder Matrix: A Retrospective Case Series.

OBJECTIVE: The purpose of this study is to assess healing outcomes in full-thickness mucosal wounds following the use of a porcine urinary bladder matrix to augment mixed oral cavity repairs. MATERIALS AND METHODS: A retrospective chart analysis was conducted over a 58-month timespan. Participants included individuals with osteoradionecrosis. Descriptive measures obtained in the postoperative setting were used to examine wound healing outcomes. RESULTS: Thirty-nine encounters with 35 patients met inclusion criteria for assessment. The mean defect size repaired was 14 cm2. Successful healing occurred in 64% of cases. Scarring was observed in 10 cases, and 3 cases demonstrated transient functional deficits. Reapplication of the xenograft was required in 4 cases. Only 1 acute event of hemorrhage and 1 infection were observed in the postoperative period. CONCLUSIONS: Use of porcine urinary bladder matrix grafts for oral cavity reconstruction was well tolerated in a diverse number of wound scenarios with a relatively low risk of postoperative complication. The use of porcine urinary bladder matrix was not observed to provide any noteworthy advantages for the healing of recalcitrant osteoradionecrosis wounds.

Ureteral reconstruction using a tapered non-vascularized bladder graft: an experimental study in a canine animal model.

BACKGROUND: Reconstruction of ureteral defects and strictures remains problematic for urologists. We aimed to investigate the possibility of a tapered non-vascularized bladder graft as a novel substitute for ureteral reconstruction. METHODS: This experimental study was conducted on nine beagles. Under general anesthesia, a full-thickness graft with 5-6 cm in length was disassociated from the anterior upper wall of the bladder, and tapered into 1/3 to 1/2 thickness, remaining the urothelial surface. After removal of 5 cm of right-sided mid-ureter, the tapered bladder graft was tubularized along the long axis and then respectively anastomosed to the upper and lower stumps of the ureter. A retrograde urography through a cystostomy was performed 8 weeks after the ureteral reconstruction. The animals were euthanized, and histopathologic examinations of the neoureters were performed. RESULTS: There were no severe complications during postoperative follow-up. The urography indicated patent urine excretion and no fistula or stenosis. Histopathologic examinations of the neoureters showed open lumen with urothelial lining. Nutrient vessels were observed in healthy submucosa, lamina muscularis and peripheral connective tissue. CONCLUSIONS: Our study implied that ureteral reconstruction by a tapered non-vascularized bladder graft was anatomically possible in our animal model. Further studies are expected to confirm long-term and functional outcomes.

Avaliação morfofuncional do enxerto de túnica albugínea suína na cistoplastia em ratos / Morpho-fuctional evaluation of porcine tunica albuginea as a graft for cystoplasty in rats

O objetivo deste trabalho é avaliar o uso da túnica albugínea suína na cistoplastia em ratos, avaliando funcionalidade, capacidade de reparação do órgão e possibilidades de complicações. Foram selecionados 30 ratos Wistar, machos, de seis meses de idade, divididos em: um grupo teste (TA), em que os animais receberam o enxerto de túnica albugínea suína após a cistectomia parcial e um grupo controle (C), em que os animais sofreram somente a cistectomia parcial. Os animais pertencentes a ambos os grupos foram divididos igualmente em subgrupos de cinco animais cada, que sofreram eutanásia em sete, 28 e 42 dias de pós-operatório. Foi realizada uma análise macroscópica e, posteriormente, uma análise histopatológica da região da ferida cirúrgica. Aos sete e 28 dias, os animais pertencentes ao grupo C e ao grupo TA apresentaram urotelização, regeneração da lâmina própria e da musculatura, porém o grupo TA apresentou menores sinais inflamatórios e maior organização tecidual, principalmente com relação à formação das fibras musculares. Aos 42 dias de pós-operatório, ambos os grupos já apresentavam características histológicas normais. Concluiu-se que o enxerto de túnica albugínea suína obteve sucesso na regeneração da bexiga de ratos, mantendo a funcionalidade do órgão, sem rejeição, e favorecendo a migração celular.(AU)

The aim of this study is to evaluate porcine tunica albuginea as a graft for cystoplasty in rats, regarding bladder function, capacity and possible complications. 30 male Wistar rats with six monthes of age have been selected and separated into two different groups: A test group (TA) in which the animals received a tunica albuginea graft after partial cystectomy and a control group (C) in which partial cystectomy was performed, followed by bladder suture. In each group the animals were euthanized at seven, 28 and 42 days after surgery. Macroscopic and Histological analysis have been performed. At seven and 28 days after surgery the samples from both groups had urothelial lining upon a lamina propria and smooth muscle fibers in regeneration process. However, the TA group showed less inflammatory signs and more organized structure, mainly regarding the smooth muscle formation. At 42 days after surgery all groups showed a bladder wall structure qualitatively identical to the normal tissue. We could conclude that tunica albuginea graft is able to maintain bladder function and support cellular migration without any kind of rejection.(AU)

Bladder Reconstruction with Human Amniotic Membrane in a Xenograft Rat Model: A Preclinical Study.

Background: Human amniotic membranes (HAMs) are assumed to have a number of unique characteristics including durability, hypoallergenic and anti-inflammatory properties. Materials and Methods: Multilayer HAMs from caesarian sections were applied to repair defined bladder defects in male Sprague-Dawley rats. The animals were sacrificed at 7, 21 and 42 days after implantation. Bladder volume capacity after grafting was measured. Histological analyses were performed to asses a number of parameters including HAM degradation, inflammatory reaction, graft rejection and smooth muscle ingrowth. Results: One rat died from sepsis in the treated group. No severe complications or signs of leakage were observed. Bladder capacity did not change over time. The initially increased inflammation in the HAM group diminished significantly over time (p<0.05). No signs of HAM degradation were observed and smooth muscle staining increased over time. Conclusions: HAMs appear to be durable and hypoallergenic grafts. The assumed suitability for the reconstruction of urinary tract justifies further research on detailed immunological process in larger grafts.

Laparoscopic Rectopexy with Urinary Bladder Xenograft Reinforcement.

BACKGROUND AND OBJECTIVES: Rectal prolapse is often repaired laparoscopically, frequently with the use of reinforcement material. Both synthetic and biologically derived materials reduce recurrence rate compared to primary suture repair. Synthetic mesh introduces potential complications such as mesh erosion, fibrosis, and infection. Urinary bladder matrix (UBM) represents a biologically derived material for reinforcement of rectal prolapse repair with the potential to improve durability without risks of synthetic materials. The objective of the study is to evaluate the effectiveness, durability, and functional result of laparoscopic rectopexy using urinary bladder matrix xenograft reinforcement at three years follow up. METHODS: The 20 cases presented describe rectal prolapse repair by means of laparoscopic rectopexy with presacral UBM reinforcement. Patients were followed up for an average of 3 years and assessed with interviews, physical examination, manometry, and the fecal incontinence severity index (FISI). RESULTS: Each repair was completed laparoscopically. UBM exhibited favorable handling characteristics when sutured to the sacrum and the lateral rectal walls. One patient underwent laparoscopic drainage of a postoperative abscess; no other complications occurred. In 3 years of follow-up, there have been no full-thickness recurrences, erosions, reoperations, or long-term complications. Two patients exhibited a small degree of mucosal prolapse on follow-up physical examination that did not require surgery. Three-year FISI scores averaged 8 (range, 0-33 of a possible 61), indicating low fecal incontinence symptomatology. Follow-up anorectal manometry was performed in 9 patients, showing mixed results. CONCLUSION: Surgeons may safely use laparoscopic rectopexy with UBM reinforcement for repair of rectal prolapses. In this series, repairs with UBM grafts have been durable at 3-year follow-up and may be an alternative to synthetic mesh reinforcement of rectal prolapse repairs. Future studies may compare the advantages and cost-effectiveness of reinforcement materials for rectal prolapse repair.

The Use of Acellular Urinary Bladder Matrix as Coverage for Fasciocutaneous Free Flap Donor Sites: An Alternative to Traditional Grafting Procedures.

PURPOSE: The purpose of this review is to 1) evaluate our early experience with urinary bladder matrix as a dressing for the management of complex wounds subsequent to fasciocutaneous or osteocutaneous vascularized tissue harvests, 2) assess coverage of exposed tendons and the duration of granulation and epithelial coverage, and 3) assess esthetic and functional outcomes compared with traditional means for the management of vascularized tissue harvest sites. PATIENTS AND METHODS: This prospective study consisted of 8 consecutive patients in whom a substantial cutaneous component was harvested as part of a vascularized tissue reconstruction, which did not permit for primary closure (n = 7) or had skin graft failure (exposed tendon) that required additional treatment (n = 1). RESULTS: Functional and esthetic outcomes were comparable to those of traditional methods of donor site closure as determined by clinical evaluation and subjective assessment by the patient. In all patients, no additional grafting was required to achieve full coverage. Irregularities of the wound achieved a level plane with granulation tissue an average of 3 to 4 weeks after surgery, followed by an additional 5 to 8 weeks for epithelialization. Wound care was minimal and included twice-daily wet-to-dry dressings. It was noted that complete wound healing was delayed in the urinary bladder matrix group, which required more attention during wound care when compared with published data. Advantages included facilitation of a robust granulation layer that leveled wound irregularities and avoidance of an additional skin graft site. CONCLUSIONS: The use of urinary bladder matrix is a viable option for the rehabilitation of donor sites of vascularized tissue that include skin. Benefits include the avoidance of an additional skin graft donor site, facilitation of epithelialization over exposed tendons, leveling of the donor site texture, and an equivalent esthetic result compared with current practices for wound coverage. The success of this technique may be limited by the cost of materials and the protracted course for wound epithelialization.