Histopathological aspects of tissue reactivity to suture materials in microsurgical arterial, anastomosis.

In order to assess tissue reactivity to synthetic suture material in microsurgery, a histological study was carried out in 20 rabbits divided into two groups: "A" and "B". The aorta of the animals was sectioned and subsequently anastomosed using polyglycolic acid in the first group and monofilament nylon in the second group. The animals were sacrificed at 10, 20, 40, 60 and 90 days after surgery, and the specimens were studied both macroscopically and microscopically. Tissue reactivity during the initial 40 days had similar histological characteristics in both groups evidentiating a perisuture granuloma with macrophages and giant cells. The second period, 40 to 90 days after surgery, was characterized by a tissue reactivity specific for each type of suture. In group "A", the inflammatory process diminished in parallel to the absorbtion of polyglycolic acid with "restitutio ad integrum" of the vessel wall. In group "B", the inflammatory process persisted due to the presence of non absorbable monofilament nylon, thus causing a fibrosclerotic transformation of the vessel wall. The results of this study suggest that the most suitable suture material for anastomosing living tissues are absorbable sutures.