Free Bladder Mucosa Research Articles

Tunneled tubularized bladder mucosal grfaft for long urethral reconstruction: is it a reliable option in selected complex cases in children and adolescents?

Aim: We analyzed the use of tubularized tunneled bladder mucosa graft (TBMG) and its application as a salvage procedure or as primary surgery for long urethroplasty in children and adolescents. Specific attention was given to a new method to harvest a long bladder mucosa graft through a minimal detrusotomy. Methods: We analyzed the files of 10 patients who underwent TBMG urethroplasty at median age of 105 months (range 20-195 months). The indications were perineal hypospadias cripple in two, masculinizing genitoplasty for ovotesticular Ovotesticular Disorder of Sex Development (DSD) in two, perineal hypospadias in four, duplicated urethra in one, and complications of circumcision in one. Staged reconstruction was performed in all patients. The first stage was removal of all fibrous tissues and efficient treatment of curvature and skin coverage. After a minimal delay of one year, a free bladder mucosa graft was harvested through a minimal detrusotomy and tubularized. Tunneling of the graft was proceeded from the perineal urethrostomy to the glans. Results: The graft was successfully harvested through the minimal detrusotomy approach for variable lengths of urethroplasty; the median length was 10.5 cm (range 8-16 cm). The median follow up was 61.7 months (range 18-160 months). TBMG was the last surgery with no redo in five cases (50%). Long stricture occurred in one case of primary perineal hypospadias and needed a redo staged surgery. Two patients performed self-dilatation for distal stenosis. Conclusion: The tunneled bladder mucosa tube graft technique represents a good alternative for a long urethroplasty in patients with a paucity of healthy skin. The minimal detrusotomy technique for graft retrieval may reduce graft harvesting morbidity.

Free bladder mucosa graft harvested by water-jet: A novel, minimally invasive technique for urethral reconstruction.

The aim of the current study was to describe a novel approach of urethral reconstruction through minimally invasive harvesting of the bladder graft via endoscopic sub-mucosal dissection of water-jet. The records of two patients were reviewed, who underwent transurethral endoscopic surgical bladder mucosa graft harvest by water-jet and urethral reconstruction with informed consent. Case 1 was a 35-year-old male with anterior urethral stricture; case 2 was a 22-year-old male with secondary anterior urethral stricture and hypospadias following a failed hypospadias surgery. The two male patients successfully underwent urethral reconstruction using bladder mucosa graft harvested via endoscopic assisted by water-jet; no perforation, cysthemorrhagia or any other postoperative bladder-related complication was observed. Voiding cystourethrogram of case 1 indicated that the reconstructed urethra was unobstructed, and no recrudescence was observed within 4 months of follow-up. In case 2, dysuria had disappeared completely within 1 month of follow-up, and the urethra plate was successfully reconstructed by first-stage. To the best of our knowledge, this is the first report to demonstrate urethral reconstruction using a bladder mucosa graft harvested by transurethral endoscopic sub-mucosal dissection, assisted by water-jet. Transurethral endoscopic surgery may provide a minimally invasive approach instead of the traditional open surgery for harvesting bladder mucosa graft. Urethral reconstruction conducted with bladder mucosa graft harvested via endoscopic sub-mucosal dissection assisted by water-jet is a feasible and safe method, and the short-term follow-up results are encouraging.

Penile Squamous Cell Carcinoma After a Childhood Hypospadias Repair With Bladder Mucosa Graft

Bladder mucosa grafts were historically used for hypospadias surgical repairs, when preputial or penile skin was unavailable and in cases of prior failed hypospadias repairs. We present a case of advanced penile squamous cell carcinoma diagnosed 22 years after a childhood hypospadias repair with a free bladder mucosa graft.

Lack of usefulness of ureteral reconstruction with free bladder mucosa flap in dogs confirmed by microangiography.

BackgroundThere is a paucity of data addressing the blood supply in the surgically reconstructed ureter, and complete lack of microangiographic studies of the reconstructed ureter with the use of a free bladder mucosa flap. The present study evaluated the blood supply in the reconstructed dog ureter after a 5-centimeter segment resection, supplemented by a tube constructed from a free bladder mucosa flap.Material/MethodsFemale mongrel dogs (n=29) were used in this study. Under general anaesthesia, a 5-centimeter autologous free bladder mucosa flap was used to construct a tube, which was afterwards grafted to replace a 5-centimeter ureter resection. After a period of 3 months (n=2) and after 1 year (n=2), microangiography was performed to assess the revascularization of the grafted ureter.ResultsIn our study, we observed the continuity of the ureter, but the grafted reconstruction was narrowed by the cicatrization in about 86% (n=25) of cases. This resulted in the development of hydronephrosis, as described in previous publications. The ureteral wall was covered by a normal urothelium, but consisted of fibrous connective tissue, which failed to restore a regular (normal) coat. The reconstructed segment showed no smooth muscle cells. A few smooth monocytes were found only at the border with intact portions of the ureter. The microangiography performed at the end of the experiments showed no vascularization of the restored segment of the ureter.ConclusionsThe experiments showed a whole regeneration of urothelium in the transected and reanastomosed ureters. However, there was no regeneration of the muscular coat and a complete lack of revascularization.

Treatment of Urethral Defects: Skin, Buccal or Bladder Mucosa, Tube or Patch? An Experimental Study in Dogs

We studied 3 graft materials and 2 urethroplasty techniques in 24 adult male mongrel dogs. The animals were divided into 2 equal groups. In group 1 a 4 cm. segment of perineal urethra was excised and tubed urethroplasty was performed using free full-thickness skin, buccal and bladder mucosa grafts in 4 dogs each. In group 2 a 4 cm. urethral strip was excised and onlay urethroplasty was performed using the same graft materials in 4 dogs each. Retrograde urethrography was done and the animals were sacrificed at week 12. Autopsy specimens were calibrated with a 10Fr catheter. Hematoxylin and eosin stained sections were examined. Masson's trichrome stain was used to determine the extent of fibrosis. Urethral stricture was diagnosed by radiology and confirmed by calibration in 8 of the 12 dogs (66%) in group 1 but in only 1 of the 12 (8%) in group 2 (p <0.004). Buccal mucosa grafts were associated with the lowest stricture rate of 12%, followed by 37% for bladder mucosa and 62% for skin (p <0.2). There was no difference in neovascularization among the 3 grafts. Graft shrinkage was less than 10% for buccal mucosa compared with 20% to 40% for skin and bladder mucosa. The shrinkage rate was similar for the onlay and tube techniques. The intensity of chronic inflammation and fibrosis was highest in the skin grafts. Circumferential fibrosis was noted in association with tubed urethroplasty but not with the onlay technique. The theoretical advantages of buccal mucosal grafts were pathologically demonstrated. When possible, grafts should be used as an onlay rather than as a complete tube.

Experience with Repair of Hypospadias Using Bladder Mucosa in Adolescents and Adults

From July 1984 to January 1994, 113 hypospadias operations were performed using a free bladder mucosa graft. There were 31 primary cases and 82 secondary cases in which prior operations had been done. The meatus was penile in 33 patients, penoscrotal in 72 and perineal in 8. The cosmetic and functional results were satisfactory. Postoperative complications included 8 fistulas that required closure and 6 cases of stenosis treated by dilation. Our results suggest that hypospadias repair with a bladder mucosa graft is feasible and reliable. The technique has been performed successfully in the most complex as well as simple cases in adults and adolescents.

Grafting of Cultured Uroepithelium and Bladder Mucosa Into De-Epithelialized Segments of Colon in Rabbits

Urinary tract reconstruction using bowel can result in acid-base and electrolyte abnormalities. We tested the feasibility of grafting bladder mucosa and urothelial cells grown on a biodegradable polyglactin 910 scaffold onto de-epithelialized segments of bowel in the rabbit. A segment of de-epithelialized colon was either grafted with cultured urothelium on a collagen mesh scaffold (12 rabbits) or with free bladder mucosa (11 rabbits). In 10 rabbits that served as a control group another segment of bowel was isolated and de-epithelialized. No urothelial or bowel epithelial growth was present 4 weeks later in 10 of the isolated deepithelialized colonic segments grafted with the cultured urothelium. In 2 segments a minute focus of epithelium staining positively for anticytokeratin antibodies AE1 and AE3 was seen but this could not be histologically differentiated as either urothelium or native colonic epithelium. All 7 surviving animals that underwent a bladder mucosal graft had viable urothelium at sacrifice 30 days postoperatively. In 2 of the 7 rabbits microscopic nests of colonic epithelium were also found underneath the urothelial layer. Of the 7 internal controls 6 had no evidence of bowel epithelial regrowth 4 weeks after deepithelialization.This study demonstrated that a confluent layer of urothelial cells could be grown in culture using a scaffold of biodegradable mesh and rat tail collagen. We also showed that bladder mucosal grafts can be grown on de-epithelialized bowel segments. We were unable to graft successfully cultured urothelial cells onto a de-epithelialized bowel segment. Further improvement in understanding the role of the submucosal matrix in cell growth may lead to future success in covering large segments of de-epithelialized bowel with autologous urothelium.

Reconstruction of Male Urethra With Free Bladder Mucosa Graft

Reconstruction of Male Urethra With Free Bladder Mucosa Graft

Bladder Mucosal Grafts: Experimental Use as a Ureteral Substitute and Observation of Certain Physical Properties

Free bladder mucosal grafts were evaluated as material for ureteral substitution. Surgical replacement of the ureter with free bladder mucosa in dogs demonstrates the feasibility of this technique. Graft patency with preservation of urothelial lining and regeneration of smooth muscle was observed. Physical properties observed during the experiment indicate a good potential for long term preservation of the graft material.

Reconstruction of the Ureter by Free Bladder Mucosa Graft: Part II. Electromyographic Studies

Reconstruction of the Ureter by Free Bladder Mucosa Graft: Part II. Electromyographic Studies