Mesh deformation: A mechanism underlying polypropylene prolapse mesh complications in vivo.

Polypropylene meshes used in pelvic organ prolapse (POP) repair are hampered by complications. Most POP meshes are highly unstable after tensioning ex vivo, as evidenced by marked deformations (pore collapse and wrinkling) that result in altered structural properties and material burden. By intentionally introducing collapsed pores and wrinkles into a mesh that normally has open pores and remains relatively flat after implantation, we reproduce mesh complications in vivo.

A soft elastomer alternative to polypropylene for pelvic organ prolapse repair: a preliminary study.

Introduction And Hypothesis: We compared the impact of a mesh manufactured from the soft elastomer polydimethylsiloxane (PDMS) to that of a widely used lightweight polypropylene (PP) mesh. To achieve a similar overall device stiffness between meshes, the PDMS mesh was made with more material and therefore was heavier and less porous. We hypothesized that the soft polymer PDMS mesh, despite having more material, would have a similar impact on the vagina as the PP mesh.

T regulatory cells and TGF-β1: Predictors of the host response in mesh complications.

Polypropylene mesh is frequently used in urogynecology procedures; however, pain and mesh exposure into the vagina occur in ~10% of cases. Mesh-induced pain, which occurs with or without exposure, persists after removal in 50% of cases. Chronic pain history predicts poor response to mesh removal but only a fraction have this diagnosis.

Characterization of the T-cell response to polypropylene mesh in women with complications.

Background: Polypropylene mesh is used widely for surgical treatment of pelvic organ prolapse and stress urinary incontinence. Although these surgeries demonstrate favorable functional and anatomic outcomes, their use has been limited by complications, the 2 most common being exposure and pain. Growing evidence suggests that T lymphocytes play a critical role in the regulation of the host response to biomaterials.

Pregnancy and parturition negatively impact vaginal angle and alter expression of vaginal MMP-9.

Background: Parity is the greatest risk factor for the development of pelvic organ prolapse. The normally supported vagina is pulled up and back over the levator ani. Loss of vaginal angulation has been associated with prolapse and may represent injury to the vaginal supportive tissues.

Towards rebuilding vaginal support utilizing an extracellular matrix bioscaffold.

Unlabelled: As an alternative to polypropylene mesh, we explored an extracellular matrix (ECM) bioscaffold derived from urinary bladder matrix (MatriStem™) in the repair of vaginal prolapse. We aimed to restore disrupted vaginal support simulating application via transvaginal and transabdominal approaches in a macaque model focusing on the impact on vaginal structure, function, and the host immune response. In 16 macaques, after laparotomy, the uterosacral ligaments and paravaginal attachments to pelvic side wall were completely transected (IACUC# 13081928).

Extracellular matrix regenerative graft attenuates the negative impact of polypropylene prolapse mesh on vagina in rhesus macaque.

Background: The use of wide pore lightweight polypropylene mesh to improve anatomical outcomes in the surgical repair of prolapse has been hampered by mesh complications. One of the prototype prolapse meshes has been found to negatively impact the vagina by inducing a decrease in smooth muscle volume and contractility and the degradation of key structural proteins (collagen and elastin), resulting in vaginal degeneration. Recently, bioscaffolds derived from extracellular matrix have been used to mediate tissue regeneration and have been widely adopted in tissue engineering applications.

Host response to synthetic mesh in women with mesh complications.

Background: Despite good anatomic and functional outcomes, urogynecologic polypropylene meshes that are used to treat pelvic organ prolapse and stress urinary incontinence are associated with significant complications, most commonly mesh exposure and pain. Few studies have been performed that specifically focus on the host response to urogynecologic meshes. The macrophage has long been known to be the key cell type that mediates the foreign body response.

Impact of parity on ewe vaginal mechanical properties relative to the nonhuman primate and rodent.

Introduction And Hypothesis: Parity is the leading risk factor for the development of pelvic organ prolapse. To assess the impact of pregnancy and delivery on vaginal tissue, researchers commonly use nonhuman primate (NHP) and rodent models. The purpose of this study was to evaluate the ewe as an alternative model by investigating the impact of parity on the ewe vaginal mechanical properties and collagen structure.

Impact of prolapse meshes on the metabolism of vaginal extracellular matrix in rhesus macaque.

Objective: The impact of polypropylene mesh implantation on vaginal collagen and elastin metabolism was analyzed using a nonhuman primate model to further delineate the mechanism of mesh induced complications.

Study Design: Forty-nine middle-aged parous rhesus macaques underwent surgical implantation of 3 synthetic meshes via sacrocolpopexy. Gynemesh PS (n = 12) (Ethicon, Somerville, NJ) and 2 lower-weight, higher-porosity, lower-stiffness meshes (UltraPro [n = 19] [Ethicon] and Restorelle [n = 8] [Coloplast, Minneapolis, MN]) were implanted, in which UltraPro was implanted with its blue orientation lines perpendicular (low stiffness direction, n = 11) and parallel (high stiffness direction, n = 8) to the longitudinal axis of the vagina.