Early Onset of Atherosclerosis of The Carotid Bifurcation in Newborn Cadavers

Abstract

Introduction: The anatomy of arterial bifurcations affects blood flow and has a significant role in the development of vascular disease. Therefore, it is important to know the structural characteristics of the Common Carotid Artery (CCA) and its branches for early onset of atherosclerosis in newborns.

Aim: The present study was conducted to evaluate the characteristics of CCA in newborn cadavers.

Materials and methods: Eight carotid arteries obtained from newborn cadavers were used. The outflow to inflow area ratios was calculated to evaluate vessel diameters. Additionally, scanning electron and light microscopic investigations were conducted with tissue samples. The brachial artery of each cadaver was used as controls. Correlation between area ratios and atherosclerotic endothelial damage was determined.

Results: Light microscopic investigations demonstrated that control group sections showed no positivity for Oil red O staining, while carotid bifurcation regions depicted widespread occurrence of intimal lipid accumulations. Scanning electron microscopic examination of control group sections presented regular endothelial topography, while carotid bifurcation region topography exhibited numerous blood cells and separated endothelial cells. Fibrin accumulation on endothelial surface in low area ratios was another important finding in the examination of its endothelial surface degeneration. The above-mentioned morphological findings seemed to be quite parallel to outflow to inflow area ratio data favouring low area and degeneration.

Conclusion: The correlation between area ratios and the histological characteristic of cerebral vessels of newborn cadavers indicate that early stages of atherosclerosis began in early embryologic life.

Keywords: Carotid artery; Cerebral blood flow; Cerebral haemodynamics; Endothelium.

[Table/Fig-1a-c]:

a) Schematic presentation of the dissection of the carotid artery. CCA: common carotid artery, ICA: internal carotid artery, ECA: external carotid artery; exposed outflow to inflow area ratio. b) Sections were photographed using a digital camera under the microscope. c) The diameters of the arteries were measured. Abbreviations: GD, greatest diameter; LD, least diameter; ID, intermediate diameter, further details in text.

[Table/Fig-2a,b]:

a) Control group from brachial artery depicted negative Oil red O staining without lipid accumulations. Light micrograph: X 400; b) Carotid bifurcation region shows positive Oil red O staining depicted widespread intimal lipid accumulations in this picture. (↓) Light micrograph: X 400, scale bar: 100 μm.

[Table/Fig-3a-h]:

a) Control group (brachial artery): Depicted undulated surface, thin endothelial cells, homogeneously intact and organized endothelium; b) Slightly disrupted surface topography of left CCA from the first case; c) Swollen endothelial cells of right CCA from the second case; d) Adhesion of numerous blood cells on the endothelium surface. Endothelial cells are slightly separated from each other. From the left CCA of the third case; e) Depicted highly separated endothelial cells with pit formation and fibrin accumulation. From the right CCA of the fourth case; f) Highly separated and swollen endothelial cells. From the right CCA of the sixth case; g) Endothelial topography is extremely disrupted with typical fibrin formation and separated endothelial cells, large pits full of adhered blood cells, from the right CCA of the eighth case; h) Extremely degenerated endothelium resulting in denuded basal lamina, from the left CCA of the fifth case, scale bar: 10 μm.

[Table/Fig-4]:

Histogram of distribution of arterial area ratios indicating that samples are homogenous for investigating the correlation N=8, Xaxis-area ratio Y axis=frequency.