Revascularization of Human Acellular Dermis in Full-thickness Abdominal Wall Reconstruction in the Rabbit Model

This study investigates whether human acellular dermis (Alloderm; LifeCell, Branchburg, NJ) revascularizes when used to reconstruct abdominal wall defects in rabbits. This could prove useful in infected situations in which prosthetic mesh is suboptimal. Twenty-five rabbits were randomly assigned to one of three groups: primary closure (n = 5), expanded polytetrafluoroethylene (GoreTex; W.L. Gore, Flagstaff, AZ) repair (n = 10), or AlloDerm (LifeCell) repair (n = 10). The rabbits in the primary closure group received a 7 cm x 0.5 cm full-thickness abdominal wall defect that was closed primarily. A 7 cm x 3 cm full-thickness abdominal wall defect was created in the other two groups. The defects were repaired with a GoreTex Mycromesh (W.L. Gore), or AlloDerm (LifeCell) patch. At 30 days, the following endpoints were evaluated: (1) incidence of herniation; (2) presence of intra-abdominal adhesions; (3) the breaking strength of the patch-fascial interface; and (4) evaluation of graft vascularization by fluorescein dye infusion and histological analysis. There was no incidence of herniation in any of the rabbits. Visceral adhesions to the patch were found in all animals in the Gore-Tex (W.L. Gore) group but in none in the AlloDerm (LifeCell) group. The size of the patch was unchanged in all the rabbits except for two rabbits in the AlloDerm (LifeCell) group that stretched 1 cm in the transverse dimension. The change in size was not statistically significant (p = 0.17) when compared with the change in size in the Gore-Tex (W.L. Gore) group. The mean breaking strength of the primary closure group was significantly higher (521.2 N/mm2 +/- 223.0) than that of the two patch-repair groups (p < 0.05). But there was no significant difference between the mean breaking strength of the AlloDerm (LifeCell) fascial interface (288.6 N/mm2 +/- 97.1 SD) and that of the Gore-Tex (W.L. Gore) fascial interface (337.0 N/mm2 +/- 141.2). Fluorescein dye infusion and histological analysis confirmed vascularization of the AlloDerm (LifeCell) graft. This study demonstrates that AlloDerm (LifeCell) does become vascularized when used as a fascial interposition graft for abdominal wall reconstruction. AlloDerm (LifeCell) also performs mechanically as effectively as Gore-Tex (W.L. Gore) in ventral hernia repair at 1 month after operation in the rabbit model.