Development of an ovine model for training in vaginal surgery for pelvic organ prolapse

This aim of this study was to evaluate the feasibility and usefulness of an ovine model for training in vaginal surgery.

Four senior urogynaecological surgeons and five residents attended five sessions of vaginal surgery for pelvic organ prolapse (POP) in five old multiparous female sheep. Urogynaecological examinations were performed and measurements similar to the POP-Q classification in humans were obtained. Standard POP surgical procedures with and without mesh were performed. A pelvic CT scan was done on one animal and the structures were compared with the pelvic structures in a woman. After the feasibility of vaginal surgery had been established in three cadavers, surgery was performed in two living animals under general anaesthesia and was followed by laparoscopy to explore the internal pelvic anatomy.

We found anatomic similarities in the vaginal and pelvic structures between sheep and women. After caudal traction on the cervix, all five sheep had significant POP of stage 3 or 4. We proved the feasibility of all types of vaginal surgery in this animal model: traditional anterior and posterior repair, apex fixation and anterior wall repair with mesh. The video shows the internal pelvic anatomy and different vaginal procedures.

This study showed that training in vaginal surgery for POP is feasible and useful in an animal model, the ewe, that has vaginal and pelvic structures very similar to those in women.