title: In vitro evaluation of the permeability of prosthetic meshes as the possible cause of postoperative seroma formation.
abstract: BACKGROUND
  Seroma formation is one of the most common post operative complications related to abdominal wall hernia repairs with mesh. We hypothesized that the different biomaterials used to construct commonly used prosthetic mesh may influence permeability to fluid and affect seroma formation rates.
  
  
  METHODS
  We designed an in vitro study where a 5 cm piece of mesh was placed in a closed system where normal saline was forced across the mesh and the pressure (mmHg) required for a constant stream of fluid was recorded. Eight prosthetic materials were studied: polyester/oxidized collagen (PC), expanded PTFE (DM), polypropylene/ePTFE (BC), polypropylene/oxidized cellulose (PR), light weight polypropylene/omega 3 fatty acid (CQ), compressed PTFE (MM), polypropylene (PP) and polyester (P) mesh.
  
  
  RESULTS
  Each mesh was tested five times and the results averaged. The 3 meshes without anti-adhesive barriers (MM, PP, P) had fluid move across with minimal pressure (<1 mmHg). For the intraperitoneal mesh, there was a significant difference in pressure necessary for fluid movement (PR = 3.6, CQ = 36, PC = 56.6, DM > 350, BC > 350 mmHg, p = <0.001). However, the fenestrations at the suture lines necessary to combine the PP and DM in the BC mesh permitted fluid transport at low pressures (<1 mmHg).
  
  
  CONCLUSIONS
  Based on our in vitro study, each mesh exhibited different fluid permeability, especially in the case of meshes with anti-adhesive barriers. This study also infers that methods to create pressure gradients across mesh, such as an abdominal binder, may reduce seroma formation of certain meshes.
authors.affiliation: Department of Surgery, Case Comprehensive Hernia Center, University Hospitals Case Medical Center, Cleveland, Ohio 44106, USA.
authors.forename: Judy
authors.initials: J
authors.lastname: Jin
authors.forename: Steve
authors.initials: S
authors.lastname: Schomisch
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Rosen
mesh_terms: D000268:Adhesiveness; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008422:Materials Testing; D046210:Microfluidic Analytical Techniques; D008954:Models, Biological; D010539:Permeability; D016062:Porosity; D011183:Postoperative Complications; D011474:Prosthesis Design / Q000009:adverse effects*; D049291:Seroma / Q000209:etiology*; D013526:Surgical Mesh / Q000009:adverse effects*