Biologic response of inguinal hernia prosthetics: a comparative study of conventional static meshes versus 3D dynamic implants.

Despite improvements in prosthetics and surgical techniques, the rate of complications following inguinal hernia repair remains high. Among these, discomfort and chronic pain have become a source of increasing concern among surgeons. Poor quality of tissue ingrowth, such as thin scar plates or shrinking scars-typical results with conventional static implants and plugs-may contribute to these adverse events. Recently, a new type of 3D dynamically responsive implant was introduced to the market. This device, designed to be placed fixation-free, seems to induce ingrowth of viable and structured tissue instead of regressive fibrotic scarring. To elucidate the differences in biologic response between the conventional static meshes and this 3D dynamically responsive implant, a histological comparison was planned. The aim of this study was to determine the quality of tissue incorporation in both types of implants excised after short, medium, and long periods post-implantation. The results showed large differences in the biologic responses between the two implant types. Histologically, the 3D dynamic implant showed development of tissue elements more similar to natural abdominal wall structures, such as the ingrowth of loose and well-hydrated connective tissue, well-formed vascular structures, elastic fibers, and mature nerves, with negligible or absent inflammatory response. All these characteristics were completely absent in the conventional static implants, where a persistent inflammatory reaction was associated with thin, hardened, and shrunken fibrotic scar formation. Consequently, as herniation is a degenerative process, the 3D dynamic implants, which induce regeneration of the typical groin components, seem to address its pathogenesis.

Deep seroma after incisional hernia repair. Case reports and review of the literature.

AIM: Wound-related complications are common after incisional hernia repair with mesh; seroma formation is the most frequent problem. The formation of a deep seroma has been rarely reported in the literature. MATERIAL OF STUDY: In one year, September 2012-2013, 136 patients underwent surgery for incisional hernia repair, both elective and urgent. RESULTS: The following complications were observed: one dislocation of polypropylene prosthesis, a massive relapsed seroma and two deep seromas described in this article. A 63- years-old female underwent open incisional hernia repair with an intraperitoneal PTFE patch. She developed recurrent seroma under the mesh drained percutaneously, and finally the prosthesis was removed. A 72- years-old male underwent open incisional hernia repair with an intraperitoneal PTFE patch. After several months the patient had seroma infection. The prosthesis was then removed. CONCLUSIONS: Seroma is a wellknown complication of postoperative ventral hernia repair, especially where prosthetic mesh is used. The formation of a deep seroma is rare. Only few works mention this complication in literature. In the development of these chronic seromas a role may be played by a long-term inflammatory reaction, more pronounced with polypropylene and polyester meshes than with ePTFE. A conservative follow up of the seromas is recommended because drainage can introduce infection. In cases where the seroma causes discomfort or is infected then drainage is necessary. From experience at our institution we suggest that patients with the deep subtype of mesh-associated seromas may require closer clinical follow up. When possible, we recommend attempting the drainage of the liquid, eventually followed by microbiological examination.