Transplantation of Autologous Peritoneum Using Ileal Seromuscular Flaps for Orthotopic Neobladder Reconstruction / 中国医学科学院学报

To develop an ideal surgical procedure for neobladder reconstruction in experimental porcine models. Six experimental female pigs weighting 28-33 kg underwent transplantation of autologous peritoneum for bladder reconstruction under general anesthesia.The flaps were used to reconstruct the orthotopic neobladder by suturing with the edges of the triangle and neck of the remnant bladder.The ureteral catheters were removed on the 5 postoperative day and the balloon catheter was removed on the 7 postoperative day.Voiding behaviour was monitored.The animals were euthanized at week 12 for routine pathology,immunohistochemistry,and electron microscopy. All the pigs survived after the surgery,and no postoperative complication such as peritonitis,intestinal obstruction,or urinary fistula was observed.All the peritoneum-ileum composite free valves survived after transplantation.Voiding behaviour was normal after catheter removal,and the urine was clear.At autopsy,reconstructed bladders were healthy.Pathological examination showed the neobladder had been covered by continuous urothelium while the peritoneum disappeared and showed no ileal mucosa regrowth and residual.Scanning electron microscope showed the transitional cells of neobladder were complete and orderly,and the urothelium around suture border was continuous and showed no malposition. Reconstruction of bladder by autologous peritoneum and ileal seromuscular flaps is an ideal approach in the experimental pigs as it can prevent regrowth of ileal epithelial cells and avoid the complications of conventional enterocystoplasty.Its clinical application deserves further investigations.

An initial experimental model of reconstruction bladder by ileal seromuscular with transplantation of autologous peritoneum / 重庆医学

Objective To develop an ideal substitution material for bladder defect ,which can reduce serious complications of urinary intestinal diversion ,we establish experimental rabbit model of reconstruction the new bladder by ileal seromuscular with transplantation of autologous peritoneum .This animal research provides the basical ground for the experimental model and further clinical application of replacement bladder .Methods Randomly ,seven experimental female rabbits were chosen ,and their body weight was 4 .0-5 .0 kg .By intravenous anesthesia ,the bladder substitute operation was carried out (to transplant the peritoneum to an ileum segment which mucosa had been removed .These flaps were used to mend and reconstruct the bladder by composite cys‐toplasty) .Animals were euthanized at 4 ,8 weeks for routine pathology and immunohistochemistry .Results Seven rabbits under‐went reconstruction ,but three were lost to complications .The length of ileum was 4 .0 cm ,and the area of substitute peritoneum was 4 .0 cm × 2 .5 cm .Voiding behaviour was normal ,and urine was clear in the remainder .At autopsy ,reconstructed bladders were healthy .Pathological examination showed that the technique was successful in creating seromuscular segments with no epithelial remnants .When applied surgically ,the seromuscular flaps with peritoneum survived at 4 weeks and the peritoneum was substituted by transitional epithelium at 8 weeks .Conclusion In this experimental rabbit model ,reconstruction bladder by autologous peritone‐um and seromuscular segment is an ideal approach for which can prevent regrowth by ileal epithelial cells and overcome the compli‐cations of conventional enterocystoplasty .Voiding behaviour is normal in the remainder .This animal study provides the basical ground for the large experimental model and further clinical application of the new enterocysplasty .

Alça intestinal invertida como substituto do ureter: estudo experimental em cães

OBJECTIVE: To investigate the outcome of ureter replacement with inverted seromuscular tube in dogs. METHODS: 40 adult mongrel dogs were divided in 5 groups of 8 animals. Each group was divided in 2 subgroups: 1 - sacrifice on 12-15 postoperative days, and 2 - sacrifice on the 60th postoperative day). In group A ureter longitudinal incision 2cm long was sewed with an inverted ileal seromuscular patch 2cm long. In group B ureter incision and patch size were 4cm long. In the remaining groups a ureter segment was replaced by an inverted ileal seromuscular tube 2cm long (group C) or 6cm long (groups D and E). In all groups, except E, ileal mucosa was removed by a grasping maneuver with a scalpel. In group E the ileal mucosa was trimmed away by blunt dissection with a scissors. The ureter permeability was tested by an intravenous urogram, and after sacrifice by anatomic exploration with a catheter. All ureter segment removed through the necropsy were analyzed by histology after hematoxilin-eosin coloration. RESULTS: The number of animals with normal urogram after the followup was: A - 2, B - 2, C - 3, D - 2 and E - 2. Histology revealed that ileal serosa was covered by ureteral mucosa grown from the ureter buds. CONCLUSION: The inverted ileal seromuscular tube or patch does not work well for ureter replacement.

OBJETIVO: Pesquisar a viabilidade da alça ileal invertida como substituto ureteral. MÉTODOS: Quarenta cães foram divididos em 5 grandes grupos de 8 animais, cada um subdividido em 2 subgrupos de acordo com a data do sacrifício (I - sacrifício em 12-15 dias de pós-operatório, e II - 60 dias de pós-operatório). Nos grupos A e B fez-se a substituição ureteral parcial com selo de íleo invertido, após abertura lateral do ureter direito com 2 (Grupo A) ou 4 cm (Grupo B) de extensão. Nos demais grupos fez-se a substituição do segmento completo do ureter usando-se um tubo de íleo invertido de comprimento equivalente ao segmento do ureter ressecado com 2cm (Grupo C) e 6cm (Grupos D e E) de extensão. A mucosa ileal foi removida por raspagem ou diérese. A permeabilidade ureteral foi testada por urografia excretora e por exploração anatômica com cateter após o sacrifício. As peças foram estudas histologicamente após preparação e coloração com hematoxilina-eosina. RESULTADOS: O número de animais com urografia normal após o seguimento foi: A-2, B-2, C-3, D-2 e E- 2. A histologia revelou que a serosa ileal se reveste com urotélio, não como decorrência de metaplasia, mas do crescimento a partir da borda da mucosa ureteral. CONCLUSÃO: Conclui-se que o íleo invertido não é um bom substituto ureteral.