Non-absorbable prosthetic meshes: which is the best option in the repair of abdominal wall defects?

The mechanical properties and macroscopic behaviour of non-absorbable materials have been widely studied. Nevertheless, biological tissue response to contact with these prostheses is not well-known. Our purpose was to compare the microscopic behaviour of two non-absorbable materials. Polypropylene and mersilene meshes were implanted on 36 female Wistar rats each (PPL and ME groups) . Six animals per group were sequentially sacrificed at 1, 2, 3, 5, 10 and 15 weeks. Global cell density and number of polymorphonuclear leukocytes, giant cells, fibroblasts and histiocytes were compared for every studied phase. The polypropylene group showed higher cell density and polymorphonuclear response in the initial phases, while scores for giant cells were higher in the mersilene group. Fibrohistiocytic reaction was increased in the polypropylene group. Polypropylene tends to provoke higher acute inflammatory reaction and connective tissue formation than mersilene. The latter induces higher foreign body reaction.

Experimentally contaminated reabsorbable meshes: their evolution in abdominal wall defects.

Contamination by septic materials may represent an important handicap in evaluating the tolerance of reabsorbable prostheses, increasing the possible onset of abdominal fistulae. This is also the case when these materials are used in the treatment of abdominal wall defects. Nevertheless, reabsorbable meshes exist that allow visceroprosthetic contact without risk, thus making it possible to use them in spite of the presence of infection. We have performed this experimental study with the aim of evaluating the behaviour and evolution of polyglycolic acid reabsorbable meshes contaminated by septic materials in the treatment of abdominal wall defects. For this purpose, 40 Wistar rats were operated and distributed into two series of 20 animals each. Massive mesh contamination by fecaloid material did not jeopardise the fact that prostheses were well tolerated in experimental animals throughout the reabsorption process, without increasing the incidence of infection.