Animal model of chronic abdominal hernia in rabbit.
ABSTRACT To create a feasible animal model of hernia that should be reliable to test the different types of mesh and/or surgical technique.
Thirty six male New Zealand albino rabbits were submitted to surgical procedure to provoke a standard hole in the abdominal wall. A metallic frame measuring 3 cm length and 1 cm width was allocated longitudinally on the umbilicus scar and the comprehensive three squared centimeters area was resected. A continuous 4.0 polyamide was performed to closure the subcutaneous and skin.
During three weeks a score of signals/symptoms was performed to evaluate the wound and clinical conditions. No death or severe complications occurred. In the 3rd week the hernia ring and visceral adhesions were evaluated. Soft omental adherences were present in the hernial sac in all animals. The area of hernia ring ranged from 32.1+/-5.5 to 35.6+/-3.1 squared centimeter and the maximum was 39 cm(2) and the minimum was 30 cm(2). The model results in protrusion which was similar to a human incisional hernia with hernia sac, visceral adhesions and fibrous healing ring.
The model was more reliable to test further techniques or mesh on hernia repair.
- SourceAvailable from: Harold Aberman[show abstract] [hide abstract]
ABSTRACT: Incisional hernias commonly occur following abdominal wall surgery. Human acellular dermal matrices (HADM) are widely used in abdominal wall defect repair. Xenograft acellular dermal matrices, particularly those made from porcine tissues (PADM), have recently experienced increased usage. The purpose of this study was to compare the effectiveness of HADM and PADM in the repair of incisional abdominal wall hernias in a rabbit model. A review from earlier work of differences between human allograft acellular dermal matrices (HADM) and porcine xenograft acellular dermal matrices (PADM) demonstrated significant differences (P < 0.05) in mechanical properties: Tensile strength 15.7 MPa vs. 7.7 MPa for HADM and PADM, respectively. Cellular (fibroblast) infiltration was significantly greater for HADM vs. PADM (Armour). The HADM exhibited a more natural, less degraded collagen by electrophoresis as compared to PADM. The rabbit model surgically established an incisional hernia, which was repaired with one of the two acellular dermal matrices 3 weeks after the creation of the abdominal hernia. The animals were euthanized at 4 and 20 weeks and the wounds evaluated. Tissue ingrowth into the implant was significantly faster for the HADM as compared to PADM, 54 vs. 16% at 4 weeks, and 58 vs. 20% for HADM and PADM, respectively at 20 weeks. The original, induced hernia defect (6 cm(2)) was healed to a greater extent for HADM vs. PADM: 2.7 cm(2) unremodeled area for PADM vs. 1.0 cm² for HADM at 20 weeks. The inherent uniformity of tissue ingrowth and remodeling over time was very different for the HADM relative to the PADM. No differences were observed at the 4-week end point. However, the 20-week data exhibited a statistically different level of variability in the remodeling rate with the mean standard deviation of 0.96 for HADM as contrasted to a mean standard deviation of 2.69 for PADM. This was significant with P < 0.05 using a one tail F test for the inherent variability of the standard deviation. No significant differences between the PADM and HADM for adhesion, inflammation, fibrous tissue or neovascularization were noted.Cell and Tissue Banking 03/2011; 12(2):135-45. · 1.17 Impact Factor