Morphological changes in tissue components of the anterior abdominal wall after experimental plastic sur-gery of a large ventral defect

Background. Currently, an active search for ways to increase the effectiveness of alloplasty of ventral hernias in experimental and clinical directions is ongoing, however, structural and functional changes in scar tissue during its reorganization, as well as the state of muscular-aponeurotic, microvascular and connective tissue components in the postoperative period, remain insufficiently studied. An analysis of the relationship between connective tissue and hemomicrocirculation, as well as a quantitative assessment of the reorganization of the microvascular bed, taking into account the dynamics of reorganization of muscular-aponeurotic structures in the anterior abdominal wall, plays a significant role in understanding the structural and functional state of the tissue. Objective. The quantitative morphological estimation of changes in microcirculatory, connective tissue and muscle-aponeurotic components of the anterior abdominal wall of rats were made after the alloplasty of considerable ventral defect by the polypropylene monofilament mesh "Prolene". Methods. Histological study was carried out in 3 days, 10 days, 1 month, 3 months and 1 year after implantation of polypropylene prosthetic device. 68 rats were distributed in 3 experimental groups: 1) the plasty by pull and approximation of wound edges with the layer by layer wound closure; 2) the plasty by the fixation of polypropylene mesh "Prolene" with the subsequent pull and approximation of defect edges; 3) the plasty by the fixation of mesh without the subsequent pull and approximation of defect edges. Using the ImageJ 1.47v software package, the relative volumes of muscle fibers, hemocapillaries of muscles and scar tissue, connective tissue stroma of muscles, neutrophilic granulocytes, fibroblasts, and collagen fibers were determined. Results and conclusion. It was revealed that mechanical tension of muscle-aponeurotic layer of abdominal wall during the pull and approximation of experimental defect edges is a substantial factor which increases the terms of scarring, and also causes the permanent degenerative processes in muscle-aponeurotic structures. It is accompanied by the deficit of microcirculatory supplement of structures, the dystrophic changes in muscular fibres, hyperplasia of connective tissue components of muscle-aponeurotic layer of anterior abdominal wall with the most prominent pathological changes from 10th day to the end of 3th month after alloplasty. Application a polypropylene mesh for the plasty without mechanical tension of muscle-aponeurotic structures optimizes the recovery and adaptation processes during the first 3 months after operation.