title: Vaginal degeneration following implantation of synthetic mesh with increased stiffness.
abstract: OBJECTIVE
  To compare the impact of the prototype prolapse mesh Gynemesh PS with that of two new-generation lower stiffness meshes, UltraPro and SmartMesh, on vaginal morphology and structural composition.
  
  
  METHODS
  A mechanistic study employing a nonhuman primate model.
  
  
  METHODS
  Magee-Womens Research Institute at the University of Pittsburgh.
  
  
  METHODS
  Parous rhesus macaques, with similar age, weight, parity and Pelvic Organ Prolapse-Questionnaire scores.
  
  
  METHODS
  Following Institutional Animal Care Use Committee approval, 50 rhesus macaques were implanted with Gynemesh PS (n = 12), UltraPro with its blue line perpendicular to the longitudinal axis of vagina (n = 10), UltraPro with its blue line parallel to the longitudinal axis of vagina (n = 8) or SmartMesh (n = 8) via sacrocolpopexy following hysterectomy. Sham-operated animals (n = 12) served as controls.
  
  
  METHODS
  The mesh-vagina complex was removed after 12 weeks and analysed for histomorphology, in situ cell apoptosis, total collagen, elastin, glycosaminoglycan content and total collagenase activity. Appropriate statistics and correlation analyses were performed accordingly.
  
  
  RESULTS
  Relative to sham and the two lower stiffness meshes, Gynemesh PS had the greatest negative impact on vaginal histomorphology and composition. Compared with sham, implantation with Gynemesh PS caused substantial thinning of the smooth muscle layer (1557 ± 499 μm versus 866 ± 210 μm, P = 0.02), increased apoptosis particularly in the area of the mesh fibres (P = 0.01), decreased collagen and elastin content (20%, P = 0.03 and 43%, P = 0.02, respectively) and increased total collagenase activity (135%, P = 0.01). Glycosaminoglycan, a marker of tissue injury, was highest with Gynemesh PS compared with sham and other meshes (P = 0.01).
  
  
  CONCLUSIONS
  Mesh implantation with the stiffer mesh Gynemesh PS induced a maladaptive remodelling response consistent with vaginal degeneration.
authors.affiliation: Magee-Womens Research Institute, Department of Obstetrics and Gynecology, School of Medicine, Pittsburgh, PA, USA.
authors.forename: R
authors.initials: R
authors.lastname: Liang
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Abramowitch
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: K
authors.initials: K
authors.lastname: Knight
authors.affiliation: Magee-Womens Research Institute, Department of Obstetrics and Gynecology, School of Medicine, Pittsburgh, PA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Palcsey
authors.affiliation: Magee-Womens Research Institute, Department of Obstetrics and Gynecology, School of Medicine, Pittsburgh, PA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Nolfi
authors.affiliation: Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Feola
authors.affiliation: Magee-Womens Research Institute, Department of Obstetrics and Gynecology, School of Medicine, Pittsburgh, PA, USA.
authors.forename: S
authors.initials: S
authors.lastname: Stein
authors.affiliation: Magee-Womens Research Institute, Department of Obstetrics and Gynecology, School of Medicine, Pittsburgh, PA, USA.
authors.forename: P A
authors.initials: PA
authors.lastname: Moalli
mesh_terms: D000818:Animals; D017209:Apoptosis; D015415:Biomarkers / Q000378:metabolism; D003094:Collagen / Q000378:metabolism; D017364:Collagenases / Q000378:metabolism; D004549:Elastin / Q000378:metabolism; D005260:Female; D006025:Glycosaminoglycans / Q000378:metabolism; D013509:Gynecologic Surgical Procedures / Q000295:instrumentation*; D020287:In Situ Nick-End Labeling; D008253:Macaca mulatta; D011126:Polypropylenes; D013526:Surgical Mesh / Q000009:adverse effects*; D014621:Vagina / Q000378:metabolism / Q000473:pathology* / Q000601:surgery
chemical_list: D015415:Biomarkers; D006025:Glycosaminoglycans; D011126:Polypropylenes; D003094:Collagen; D004549:Elastin; D017364:Collagenases