Page 335 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

appropriate prosthesis. The most commonly used meshes in hernia repair are made of non-absorbable materials, in particular polypropylene and polyester. These materials are relatively inexpensive, easy to handle, and incorporate well into the abdominal wall. However, when placed in contact with the abdominal viscera, complications of adhesion formation can occur, associated with abdominal pain, small bowel obstruction, bowel erosion, enterocutaneous stulas, and complicated future abdominal surgery(45-48). Contact with viscera is more common in laparoscopic repair and during the repair of complex or large abdominal wall hernias, with loss of domain or the inability to close the fascia completely. Furthermore, mesh infection can follow either open or laparoscopic hernia repair. Incidences of mesh infection after open repair range between 6-10%; and 0-4% after laparoscopic repair(49-51). Implantation of a mesh in a contaminated environment increases the risk of surgical site infections, including mesh infection(50, 52). For mesh use intraperitoneally or in contaminated elds, alternatives can be found in composite and biological meshes. Composite meshes are synthetic meshes with an additional layer or coating on the visceral side of the mesh. Biological meshes are collagen sca olds derived from human or animal donors.
The results of the experiments described in part 2 of this thesis show a wide range of performance for biological meshes between clean and contaminated environments. Besides the infection susceptibility of some biological meshes, incorporation is found to be a problem for all biological meshes. This poor incorporation makes sustainable hernia repair questionable. The results of our animal experiments are in accordance with published results of recurrence rates of up to 80% in human hernia repair with biological meshes(53-59). Human studies reporting on the outcomes for biological meshes in hernia repair are scarce, report small numbers, are mostly single-institution based, and vary widely in follow-up time, operative technique, and patient selection(53). Furthermore, con ict of interest statements are often not reported(53). A limitation of our experiments might be the implantation of biological meshes in an intraperitoneal position. After intraperitoneal placement of a mesh, there is no close vascular supply to facilitate neovascularisation, and broblasts have di culty reaching the mesh(60). However, in previous animal studies intraperitoneal or extraperitoneal implantation of the mesh did not a ect host tissue incorporation or mesh degradation(61). In the retrospective analysis of the RICH study, there was no di erence found in hernia recurrence rate when
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General discussion and future perspectives
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