FEATURES OF GRANULATION TISSUE MORPHOLOGY AROUND THE NET ALLOTRANSPLANT WHEN APPLYING POSTOPERATIVE RADIATION THERAPY

The aim of the research was to study experimentally the morphologic peculiarities of the granular tissue around the elements of the reticular allotransplant of the muscular aponeurotic layer of the anterior abdominal wall when using postoperative distant gamma therapy. The experiment has been done on 168 laboratory rats which were implanted with a prolenic mesh allograft into the tissues of muscular aponeurotic layer of the anterior abdominal wall. From the 13th to 19th day after the implantation of the reticular allograft, animals from the main group (96 rats) received irradiation of the site of the last one. Taking of the biological material was carried out on the 20th, 30th, 40th and 50th day after surgery. For optical research at histological examination the samples of biopsy were fixed in 10% neutral formalin. Paraffin sections were stained with hemotoxylin and eosin. To identify collagen fibres the method of histological sections' coloring was applied. The results of the research indicate that the use of distant gamma therapy after reticular allotransplant implantation leads to uneven maturation of the granulation tissue, its edema, probable decrease in the percentage of fibroblasts, increase of lymphoid cells as well as the appearance of plasma cells and macrophages on the 40th and 50th days of observation. At the histologic sections coloring with aquious blue-chromotrope B2, there is a predominance of the specific volume of collagen fibers and an increase in the specific volume of blood vessels on the 50th day of observation. Thus, the use of the postoperative radiotherapy at the plasty of the anterior abdominal wall with a reticular allograft leads to the distortion of the maturation process of the granular tissue, its edema, which shows itself in the probable reduction in the percentage of fibroblasts, increase in lymphoid cells, appearance of plasma cells and macrophages as well as prevalence of specific volume of collagen fibres, increase in the specific volume of vessels.