Pathomorphological manifestations of vascular remodeling in the perifocal areas of ischemic cerebral infarction

Abstract

Abstract. Acute disorders of cerebral circulation remain one of the leading causes of death of patients throughout the world. Tissue recovery after a stroke is directly related to active revascularization, which is intensified in the peri-infarction area. Newly formed vessels contribute to the restoration of cellular metabolism in surviving neurons. The processes of vascular remodeling after stroke have been at the center of many clinical and morphological studies in recent years. The aim of the study. To study the processes of vascular remodeling and neoplasm of vessels in the perifocal areas of ischemic cerebral infarctions. Material and methods. The study researched the brain of 29 deceased patients with hemispheric infarctions with different periods of the disease: up to 3 days (n = 5), 6 days (n = 5), 9-12 (n = 10), 30 (n = 5), 45 days (n = 4). The object of the study was perifocal areas of cerebral infarction, as well as areas outside ischemic lesions. The studies were carried out using histological, morphometric and statistical techniques. Results. Studies have shown that in the perifocal areas of cerebral infarction within 3 days from the onset of the disease, the morpho-functional state of the microvasculature was characterized by circulatory and hemocoagulation disorders. Along with destructive changes in blood vessels, processes are directed to improve blood circulation in ischemic areas of the brain. Collateral blood flow increases, dilation of pial vessels is noted with a decrease in the Kernogan index. On the 6th day, the processes of angiogenesis and vasculogenesis are activated, which intensify in the subsequent stages of the disease. In the long term, the efficiency of collateral blood flow in the pial vessels decreases, reduction in the capillary network, and the lumen of large arteries is recalibrated. Conclusions. In the early stages of cerebral stroke (up to 3 days), increased blood circulation in the ischemic areas of the brain occurs due to increased collateral blood flow. From the 6th day, the processes of angiogenesis in the form of capillary budding and the processes of vasculogenesis intensify. In large arterioles, recalibration processes take place. After 30-45 days in the perifocal areas of cerebral infarction, a significant reduction of the capillary network is recorded, which is regarded as a reaction to a decrease in blood supply to the areas of organized infarction.