Morphometric characteristics of neovascularization of carotid atherosclerotic plaques

OBJECTIVE: to identify the relationship between the magnitude of neovascularization of an atherosclerotic plaque and its other processes, such as atheromatosis, macrophage responses, hemorrhages, and calcification. MATERIAL AND METHODS: ; density of vessels of different diameters; localization in section), atheromatosis (a volume fraction), foam cells (a score of 0 to 5), hemorrhages (a score of 0 to 4), and calcification (a score of 0 to 4). The Mann-Whitney U test and the Spearman correlation coefficient with p<0.05 were used in the statistical analysis. RESULTS: There was a substantial variability in vessel diameters and densities in the plaque with a drastic predominance of vessels smaller than 20 µm in diameter (69.8±14.3%). The vessels with a diameter as large as 20 µm were more frequently located in the area of accumulation of foam cells or organizing hemorrhages (p<0.03), unlike those with a diameter of more than 40 µm, which were more common in the areas of connective tissue, especially adjacent to large calcifications, and in the foci of organized hemorrhages (p<0.008). Intensified calcification was accompanied by the higher density of vessels having a diameter of more than 40 µm (p<0.038) and particularly of those with a diameter of more than 60 µm (p=0.006). The degree of hemorrhages and the number of foam cells were unrelated to the density of vessels, but these increased with their localization in the surface areas of a plaque (p=0.000342). With the increasing severity of atheromatosis, there was a decrease in the density of vessels larger than 20 µm in diameter (p=0.00042). CONCLUSION: The number, diameter, and location of vessels in the plaque serve as a dynamic reflection of its destructive and reparative processes; and a larger number of vessels having a diameter of more than 40 µm can be an indicator for the activation of reparative processes.