Page 17 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

The early meshes of polyester, polyethylene, polypropylene, and e-PTFE provided solid repair of the abdominal wall. However, these meshes were sometimes found to induce infectious complications, and adhesion formation when in contact with abdominal viscera. For these reasons, composite meshes with antibacterial and anti-adhesion coatings were developed, generating promising results. The anti-adhesive layer, added to a synthetic mesh, was designed to function as a barrier between the viscera and the mesh, reducing the risk of adhesion formation. However, implantation of synthetic meshes in infected environments remained problematic, with a high rate of mesh infections. Over the last decade, in response to this challenging indication, biological meshes of collagen have been developed, derived from animal or human donor tissue. These biological meshes were especially developed to be implanted in a contaminated or infected environment requiring closure. These biological collagen meshes are thought to be replaced by the patient’s own collagen in time (remodeling), with associated low adhesion-formation, and a low infection risk. They are less suitable for bridging, however, because gradual absorption occurs, the risk of recurrence possibly being higher in such a case. The short-term results of biological mesh use for complicated abdominal wall repair seem promising, but long-term results on recurrence rates are not yet available. The Ventral Hernia Working Group have developed an incisional hernia grading system based on the characteristics of both the patient and the wound. It advises the use of a biological mesh in potentially contaminated environments (grade 3, i.e. patients with a previous wound infection, a stoma present, or involving an operation with violation of the gastrointestinal tract); and infected environments (grade 4, i.e. patients with an infected mesh or septic dehiscence)(29). Since long-term results are not yet available, and the cost of biological meshes is very high compared to synthetic meshes, evidence of superiority is necessary before widespread use of biological meshes can be justi ed.
Outline of the thesis
The rst aim of this thesis is to determine the current incidence of IH, and the best surgical technique to prevent it. The second aim of this thesis is to study the treatment of IH, especially the repair of large IHs, and repair techniques using the novel biological and composite meshes.
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Introduction and outline of the thesis
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