Reconstruction of rabbit urethra with surgisis small intestinal submucosa.

PURPOSE: To evaluate the efficacy of Surgisis, porcine small intestinal submucosa, in the reconstruction of iatrogenic urethral defects in rabbits. MATERIALS AND METHODS: Eight male white rabbits were enrolled in this protocol. A 2.5-cm segment of urethra was excised. One control consisted of a normal urethra. The other rabbits underwent urethroplasty with Surgisis and 6-0 Vicryl running suture. An 8F feeding tube was left in place to divert urine for 2 weeks after surgery. Retrograde urethrograms were performed to assess the patency of the urethras and to rule out fistula formation prior to sacrifice of the animals. The sacrifice protocol began with the control and a urethroplasty animal 6 weeks after surgery. The other rabbits were euthanized at 2-week intervals thereafter. RESULTS: Surgisis promoted epithelial regeneration in all cases. One animal developed a wound infection; this was associated with a small fistula at the proximal end of the anastomosis. Good cosmetic and functional results were documented. Retrograde urethrograms showed no stricture formation at the site of the anastomosis in six rabbits. The histopathologic examination showed complete regeneration of all urethral layers, almost indistinguishable from the normal urethra. CONCLUSION: Surgisis is an excellent material for urethral reconstruction in rabbits. It promotes regeneration of all the components of the host urethral layers and is biodegradable.