title: Comparison of a lightweight polypropylene mesh (Optilene® LP) and a large-pore knitted PTFE mesh (GORE® INFINIT® mesh)--Biocompatibility in a standardized endoscopic extraperitoneal hernia model.
abstract: OBJECTIVE
  The use of a mesh with good biocompatibility properties is of decisive importance for the avoidance of recurrences and chronic pain in endoscopic hernia repair surgery. As we know from numerous experiments and clinical experience, large-pore, lightweight polypropylene meshes possess the best biocompatibility. However, large-pore meshes of different polymers may be used as well and might be an alternative solution.
  
  
  METHODS
  Utilizing a totally extraperitoneal technique in an established animal model, 20 domestic pigs were implanted with either a lightweight large-pore polypropylene (PP) mesh (Optilene® LP) or a medium-weight large-pore knitted polytetrafluorethylene (PTFE) mesh (GORE® INFINIT® mesh). After 94 days, the pigs were sacrificed and postmortem diagnostic laparoscopy was performed, followed by explantation of the specimens for macroscopic, histological and immunohistochemical evaluation.
  
  
  RESULTS
  The mean mesh shrinkage rate was 14.2% for Optilene® LP vs. 24.7% for INFINIT® mesh (p = 0.017). The partial volume of the inflammatory cells was 11.2% for Optilene® LP vs. 13.9% for INFINIT (n.s.). CD68 was significantly higher for INFINIT (11.8% vs. 5.6%, p = 0.007). The markers of cell turnover, namely Ki67 and the apoptotic index, were comparable at 6.4% vs. 12.4% (n.s.) and 1.6% vs. 2.0% (n.s.). In the extracellular matrix, TGF-β was 35.4% for Optilene® LP and 31.0% for INFINIT® (n.s.). Collagen I (pos/300 μm) deposits were 117.8 and 114.9, respectively.
  
  
  CONCLUSIONS
  In our experimental examinations, Optilene® LP and INFINIT® showed a comparable biocompatibility in terms of chronic inflammatory reaction; however, the shrinkage rate was significantly higher for INFINIT® after 3 months. The higher shrinkage rate of INFINIT® should be taken into account when choosing the mesh size for an adequate hernia overlap.
authors: Department of Surgery and Center for Minimally Invasive Surgery, Vivantes Hospital Spandau, Neue Bergstr. 6, 13585, Berlin, Germany. dietmar.jacob@vivantes.de
authors: Dietmar A
authors: DA
authors: Jacob
authors: Christine
authors: C
authors: Schug-Pass
authors: Florian
authors: F
authors: Sommerer
authors: Andrea
authors: A
authors: Tannapfel
authors: Hans
authors: H
authors: Lippert
authors: Ferdinand
authors: F
authors: Köckerling
mesh_terms: D034861:Abdominal Wall / Q000473:pathology; D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D001707:Biopsy, Needle; D004195:Disease Models, Animal; D006552:Hernia, Inguinal / Q000601:surgery*; D059685:Herniorrhaphy / Q000379:methods*; D007150:Immunohistochemistry; D010535:Laparoscopy / Q000379:methods*; D008422:Materials Testing; D011126:Polypropylenes / Q000737:chemistry; D011138:Polytetrafluoroethylene / Q000737:chemistry; D011897:Random Allocation; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D013526:Surgical Mesh; D034421:Sus scrofa; D013552:Swine; D014945:Wound Healing / Q000502:physiology
chemical_list: D001672:Biocompatible Materials; D011126:Polypropylenes; D011138:Polytetrafluoroethylene