Purpose: To evaluate the biocompability and histological changes of the porcine intestine submucosa (SIS) used for bladder augmentation in dogs. Methods: eight mongrel dogs underwent laparotomy and a 3cm full-thickness midline cistotomy was performed in its ventral surface. In order to produce an immediate augmentation of the bladder, a porcine SIS patch graft was implanted. On the 30th post-operative day the animals were submitted to a second operation for a grossly evaluation of the implanted graft. Results: there was no finding of seroma, hematoma, abscess, fistula, adhesion and stone formation. The bladder was then removed for histological studies and the animals were sacrificed. A chronic inflammatory process was observed in all animals. The urothelium covered the implant in 100% of the cases and smooth muscles fibers were seen in the graft area. The angiogenesis was significant and reabsorption of the implanted submucosa could be observed. The densitometry of collagen showed that the area occupied by immature collagen type III was greater than the area occupied by the mature collagen, type I. Conclusion: SIS can be used as a bladder substitute, since it acts as a scaffold for tissue regeneration.
Intestine, Small; Surgical Flaps; Bioprosthesis; Bladder; Dogs
