title: Intraperitoneal onlay mesh: an experimental study of adhesion formation in a sheep model.
abstract: OBJECTIVE
  Current hernia literature shows that the use of mesh in ventral hernia repair reduces the risk of recurrence significantly. In laparoscopic repair, the mesh is placed intraperitoneally. Accordingly, the close contact between mesh and viscera involves a risk of adhesion formation. In this experimental study, we examined the degree of de novo adhesion formation over time to currently available meshes.
  
  
  METHODS
  Sixteen sheep each received laparoscopic placement of four (10 x 10 cm) meshes on intact peritoneum. Two different mesh materials (coated vs. non-coated) and two different fixation devices (absorbable/non-absorbable) were investigated. (Parietex Composite, DynaMesh IPOM, ProTack and AbsorbaTack). After 3, 6, 12 and 18 months, four animals, respectively, underwent a new laparoscopy to determine the extent of adhesions to the mesh.
  
  
  RESULTS
  Parietex Composite significantly reduced the formation of intraabdominal adhesions compared to DynaMesh IPOM. The mean extent of adhesions increases over time without reaching a steady state within the first 12 months after laparoscopic placement.
  
  
  CONCLUSIONS
  This is the first long-term (18 months) experimental study on adhesion formation in sheep after laparoscopic placement of mesh and may serve as a template for future studies on meshes before marketing.
authors.affiliation: Surgical Department, Horsens Regional Hospital, Sundvej 30, 8700, Horsens, Denmark. nellie@zinther.dk
authors.forename: N B
authors.initials: NB
authors.lastname: Zinther
authors.forename: P
authors.initials: P
authors.lastname: Wara
authors.forename: H
authors.initials: H
authors.lastname: Friis-Andersen
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D006555:Hernia, Ventral / Q000601:surgery*; D010535:Laparoscopy; D009852:Omentum; D010529:Peritoneal Cavity; D012756:Sheep; D013526:Surgical Mesh / Q000009:adverse effects*; D013997:Time Factors; D000267:Tissue Adhesions / Q000175:diagnosis* / Q000209:etiology