Long-term histologic response to synthetic and biologic graft materials implanted in the vagina and abdomen of a rabbit model

Abstract

We sought to evaluate the effects of graft type, site of implantation, and ovariectomy on the long-term histologic response to graft materials used in pelvic reconstructive surgery. In all, 45 rabbits underwent ovariectomy or sham laparotomy and were implanted with polypropylene (PP) mesh (n = 23) or cross-linked porcine dermis (PS) (n = 22) in the vagina and abdomen. Grafts were harvested 9 months later and were processed for histology to evaluate the host inflammatory response and degree of tissue incorporation within the grafts. Polypropylene induced a milder (P < .007), more uniform response than PS, whereas PS elicited a more variable response and degraded by 9 months. Vaginal grafts had higher scores for inflammation (P = .005) and neovascularization (P < .001), and had lower scores for fibroblastic proliferation (P < .001) than abdominal grafts. Ovariectomy had no effect (P > .05). Synthetic and biologic grafts evoke different foreign body responses, which may have implications for surgical outcomes in women.