Host reaction to vaginally inserted collagen containing polypropylene implants in sheep

Objective We aimed to characterize the effect of vaginalor abdominal mesh insertion and of different collagen augmentation of polypropylene mesh in a sheep model. Outcome measures were passive and active biomechanical properties and semiquantitative morphometry. Study Design Forty-two Texel sheepwere used: 6 were nonimplanted controls (n = 6), the rest were implanted with polypropylene mesh (n = 12; Avaulta Solo; Bard Medical, Covington, GA) or collagen-coated meshes: Avaulta Plus (n = 12; Bard Medical) and Ugytex (n = 12; Sofradim International, Trevoux, France). Through a single incision, the rectovaginal septum was dissected and a 35 × 35–mm mesh was sutured to the underlying tissues. Abdominally, a 50 × 50–mm mesh was laid over a primarily sutured full thickness 40-mm longitudinal incisional defect. Animals were explanted after 60 or 180 days (n = 6 per group). Outcome measures were passive biomechanics by biaxial tensiometry, active contractility of vaginalexplants, and histologic evidence. Results Vaginalexplants were 2.4 times stiffer compared with native vaginaltissue ( P P = .032) and Ugytex ( P = .015). Abdominal explants were 1.3-times stiffer compared with native abdominal wall tissue ( P Conclusion Vaginalmesh implantation yields less stiff explants compared with abdominal explants. Vaginalmesh implantation also alters the passive and active biomechanical properties compared with native vaginaltissues. Collagen matrices did not reduce the number of graft-related complications.