Prolene (Polypropylene) is a gold standard for repairing ventral or incisional hernias but exhibits increased inflammatory responses as a non-absorbable foreign material and causing post-operative complications. Prolene composite mesh has a reduced polypropylene concentration in addition to an equal proportion of absorbable material. Hence they provide more tissue in-growth and less inflammatory response and minimal adhesion formation.
The present project was designed to compare the two mesh implants viz., the simple non-absorbable poly-propylene (prolene) mesh and the prolene-vicryl composite mesh which is comprised of an outer latticework of the non-absorbable polypropylene, in addition to absorbable polyglactin 910 (vicryl) on the inner side. Both mesh implants are readily available in Pakistan; the non-absorbable polypropylene mesh is available in Pakistan with the Trade name of Prolene® (Ethicon, Johnson & Johnson, USA), while the prolene-vicryl composite mesh is available with the Trade name of Vypro® (Ethicon, Johnson & Johnson, USA). Both meshes were compared on the basis of post-surgical complications (Pain evaluation, wound healing, hematoma, seroma and abscess formation), inflammatory responses mesh shrinkage and adhesion formation after application of hernioplasty implant.
The experimental study was conducted on 12 (twelve) healthy mongrel dogs to compare prolene and prolene-vicryl composite mesh for ventral or incisional hernia repair in dogs. The dogs were randomly selected as either male or female, aged between one to two years (mean age 1.5 years). The body weight of the experimental animals was in the range between 16-20 kg (mean weight 18 kg). The dogs were housed in kennels at Pet Centre of University of Veterinary and Animal Sciences, Lahore for a period of 3 months (including adaptation and post-operative period). The dogs were divided into three groups (A, B & C) comprising of 4 dogs in each group; and they were numbered from # 1-4 in Group A, #5-8 dogs in Group B, and #9-12 dogs in Group C, for proper identification and for ease of research. The respective meshes were used for ventral or incisional hernia repair in group A and group B dogs, while group C dogs served as control group.
The groups were surgically treated as follows:
Group A (Prolene mesh)
Group B (Prolene-vicryl composite mesh)
Group C (Control group)
During experimental trials, it was seen that polypropylene mesh resulted in a persistent inflammatory response, prominent foreign body reaction, rare vascularization, more fibroblast more granulating tissue, increased thickness of connective tissue, and extensive collagen fiber. In comparison, the polypropylene-vicryl composite mesh resulted in better vascularization, rare inflammatory response, moderate collagen fiber formation, smooth incorporation of collagen fibers into the mesh, low foreign body reaction, less fibroblast proliferation and lesser granulating tissue.
Based upon all the findings it was concluded that the Prolene-Vicryl composite mesh is safer and more effective in terms of post-operative complications and outcomes.