[Structural and functional tissue response to implants in patients with recurrent abdominal wall hernias in long-term...

To analyze long-term structural and functional changes of connective tissue in patients with recurrent hernias after repair with implants.

Excisional biopsies from the hernia recurrence sites were performed in 60 patients who had previously undergone hernia repair with implants. In 37 (62%) patients, polypropylene mesh of the unidentified manufacturer was previously implanted. Eight (13%) patients underwent PROLENE polypropylene mesh implantation, 4 (5%) patients - Ultrapro partially absorbable lightweight mesh composed of approximately equal parts of non-absorbable polypropylene fibers and absorbable poliglecaprone fibers, 4 (7%) patients - polyethylene terephthalate meshes of the unidentified manufacturer, 8 (13%) patients - PROCEED™ surgical mesh with absorbable anti-adhesive coating.

There were chronic inflammation foci at the site of recurrence in 1-5 years after implantation. Macrophages and mast cells were in active functional state. After 6-10 years, implant-induced fibrosis with areas of hyalinosis around the implant developed. There were fractures, cracks and other defects on threads of unidentified polypropylene implant and Prolene endoprosthesis. After 19 years, fragments of polyethylene terephthalate endoprosthesis were surrounded by giant cell granulations with tissue hyalinosis at the site of recurrence.

Polypropylene and polyethylene terephthalate endoprostheses were subject to destruction over time (after 7 years in our study). Any implant causes persistent inflammation many years later. Desynchronization of inflammation and regeneration phases can lead to excessive connective tissue with its subsequent fibrous transformation and implant deformation in long-term period (up to 19 years).