Adhesion formation of a polyvinylidenfluoride/polypropylene mesh for intra-abdominal placement in a rodent animal model

Abstract
Effective laparoscopic ventral herniorrhaphy mandates the use of an intraperitoneal mesh. Visceral adhesions and shrinkage of prosthetics may complicate repairs. The aim of this study was to compare adhesion formation, mesh shrinkage and tissue ingrowth after intra-abdominal placement of a novel two-component monofilament mesh structure made of polypropylene (PP) and polyvinylidenfluoride (PVDF) with current alternatives. Forty Sprague-Dawley rats were used in this study. Mesh samples were fixed as intra-abdominal only mesh at the right lateral abdominal wall. The study groups were: PVDF+PP (polypropylene parietally and polyvinylidenfluoride viscerally), PP+Col (polypropylene with a collagenoxidized film), ePTFE (smooth surface viscerally and a textured surface parietally), and PP (a pure polypropylene mesh serving as control). The meshes were explanted after 30 days. Adhesions were scored as a percentage of explanted biomaterials’ affected surface area; prosthetic shrinkage was calculated. Foreign-body reaction to mesh materials was measured by investigating the amount of inflammatory infiltrate and fibrotic tissue formation. In terms of adhesion score, the pure PP mesh showed the highest values followed by the ePTFE, PVDF+PP, and PP+Col meshes. Quantitative assessment of adhesion area revealed a significantly higher value of the pure PP mesh sample (62.0 ± 22.1%) compared with the PP+Col (26.8 ± 12.1%) and the PVDF+PP mesh (34.6 ± 8.2%). Percentage of shrinkage showed a significantly higher value of the ePTFE mesh (52.4 ± 13.9%) compared with all other mesh modifications (PP+Col 19.8 ± 13.9%, PVDF+PP 19.9 ± 7.0%, and PP 26.8 ± 9.5%). Inflammatory infiltrate was significantly reduced in the PVDF+PP mesh group compared with all other mesh samples. The use of the novel two-component monofilament mesh structure made of polypropylene and polyvinylidenfluoride was found to be favorable regarding adhesion formation and mesh shrinkage compared to conventional mesh materials used for intra-abdominal placement.