Formation of a vesicovaginal fistula in a pig model

OBJECTIVE: To establish an animal model of a vesicovaginal fistula that can later be used in the development of new treatment modalities. MATERIALS AND METHODS: Six female pigs of Landrace/Yorkshire breed were used. Vesicotomy was performed through open surgery. An standardized incision between the bladder and the vagina was made, and the mucosa between them was sutured together with absorbable sutures. A durometer ureteral stent was introduced into the fistula, secured with sutures to the bladder wall, allowing for the formation of a persistent fistula tract. Six weeks postoperatively cystoscopy was performed to examine the fistula in vivo. Thereafter, the pigs were euthanized with intravenous pentobarbital. RESULTS: Two out of four (50%) pigs developed persistent fistulas. No per- or postoperative complications occurred. CONCLUSION: This study indicates that this pig model of vesicovaginal fistula can be an effective and cheap way to create a fistula between the bladder and vagina.