Fate of collagen-based implants used in pelvic floor surgery: A 2-year follow-up study in a rabbit model

OBJECTIVE: The purpose of this study was to compare the long-term host response to 2 different collagen matrices versus macroporous polypropylene mesh. STUDY DESIGN: Four full-thickness abdominal wall defects in 35 rabbits were reconstructed with either polypropylene (Prolene), porcine dermal (Pelvicol), or small intestine submucosal collagen matrix (SIS). Animals were sacrificed on day 30, 60, 90, 180, 365, 540, and 720 days to evaluate morphologic and biomechanical properties of explants. RESULTS: Prolene provoked a fibrotic reaction within 30 days. SIS was entirely replaced by a thin fibrotic layer within 60 days. Pelvicol was encapsulated, remaining structurally unchanged up to 180 days. Thereafter, half underwent degradation by a foreign body reaction. CONCLUSION: Prolene was integrated by an increasingly organised fibrotic scar while SIS was entirely remodelled within 60 days. Pelvicol implants underwent late onset (>= 180 days) degradation. After 2 years of implantation there were no differences in tensiometric strength between the 3 different materials.