Page 225 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

The literature clearly shows that Surgisis manifests enhanced shrinkage and is absorbed completely by the body. However, the speed of degradation is a matter of discussion(19, 31-33).
One advantage attributed to biodegradable meshes is their ability to support regeneration of the original tissue, but when the mesh degrades before adequate cellular in ltration, di erentiation, collagen deposition, and neovascularization, the overall quality and strength of the newly formed tissue probably will be insu cient for abdominal hernia repair(19, 34).
Histologic examination of Surgisis after picrosirius red staining showed a transition layer with collagen bers organized in di erent directions crossing the border between Surgisis and surrounding tissue. Together with degradation of the mesh, this suggests an ongoing remodeling process. Unfortunately, from the results of this study, it is not possible to conclude what in uence the remodeling process has on the strength of the mesh and underlying tissue.
In our study, a wide variation in adhesion formation to the mesh was seen in the Strattice group at 30 days. In two cases, less than 5 % of the surface was covered with adhesions, whereas in two additional cases, organs were attached to the Strattice mesh. Remarkably, the amount of adhesions attached to the mesh dropped dramatically from 40 % at 30 days to 5 % at 90 days. In combination with a signi cant lower tenacity of adhesions compared with the Prolene mesh at 90 days, this may suggest less severe adhesion formation to Strattice mesh in the long term. This may be explained by the histologic result similar to that of Parietex composite meshes, showing a new mesothelial layer at the visceral side of the mesh.
Our result of a wide variation at 30 days is consistent with that of Mulier et al.(35), who also found a wide distribution in adhesion formation. However, they did not mention whether any organs were involved or not. At 90 days, 40 % of the Strattice mesh edge was incorporated into the abdominal wall. In contrast to the results at 30 days, correlation between adhesions and incorporation could not be found anymore because very few adhesions were seen. Histologic examination with picrosirius red staining showed almost no degradation of the mesh. Additionally, a small and sharply bordered layer of novel connective tissue was seen between the mesh and the abdominal wall, con rming the macroscopic observation of limited incorporation.
The amount of adhesions to Permacol mesh after 90 days (74.8 %) was signi cantly diminished compared with the amount after 30 days (87.5 %),
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Biological mesh in hernia repair
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