Page 226 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Chapter 10
whereas the Zühlke score was not. This may be explained by the reduction in lmy adhesions, whereas, in contrast, bowel or liver adhered to 57 % of the meshes. In the literature, these extensive adhesions and limited adhesion formation to Permacol mesh are described(36, 37).
Mesh edge incorporation at 90 days was 21 %, and in contrast to Strattice and Surgisis, no correlation between adhesion formation and incorporation was found at either time point. Histologic examination after 30 days showed a substantial brotic layer between the Permacol mesh and the abdominal wall, and picrosirius red staining did not show a transition layer with degradation of the mesh or new collagen formation. Additionally, the macroscopic observation of liver adhered to the mesh was microscopically con rmed with a brotic reaction between liver and mesh (Figure 5).
These observations suggest that Permacol mesh placement results in a foreign body reaction comparable with that of synthetic meshes, resulting in formation of a brotic capsule rather than tissue regeneration. An explanation may be found in the chemical cross-linking process. The aim of this process is to increase the strength of the sca old and to restrain the in vivo degradation process. A disadvantage may be that cross-linking results in biocompatibility, possibly leading to more adhesion formation. Therefore, based on results in this study, non-cross-linked mesh should be preferred to prevent strong adhesion formation.
We conclude from this study that biologic meshes are not necessarily superior to synthetic meshes with regard to adhesion formation, incorporation, or shrinkage. Our data con rm the outcome of earlier studies in which composite meshes showed clear advantages compared with other meshes on the market(38, 39). The di erence in our results between 30 and 90 days appears to be highly signi cant and should lead to careful interpretation of short-term experimental results.
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