[Atherosclerosis of the vessels of Willis' circle in certain variants in its structure]

Area of Science:

• Neuroanatomy
• Vascular Biology
• Gerontology

Background:

• The Circle of Willis is a critical arterial network at the base of the brain.
• Understanding variations in its structure is essential for neurological health.
• Age-related changes, like atherosclerosis, can impact cerebral blood flow.

Purpose of the Study:

• To investigate the structural variants of the Circle of Willis in a male cohort aged 50-64.
• To analyze the prevalence and characteristics of atherosclerotic changes in these vessels.
• To correlate specific arterial structures with the degree of atherosclerosis and potential blood supply alterations.

Main Methods:

• Post-mortem examination of the base of the brain vessels in 278 deceased men (aged 50-64).
• Identification and classification of 29 distinct structural variants of the Circle of Willis.
• Assessment of atherosclerotic changes in each identified cerebral vessel.

Main Results:

• Twenty-nine variants of the Circle of Willis structure were identified, with threadlike connective arteries and posterior trifurcations of the inner carotid arteries being most common.
• A statistically significant increase in the average degree of atherosclerosis was observed in the posterior trifurcations.
• Atherosclerotic changes in posterior connective arteries were only detected when their diameter exceeded 0.1 cm, suggesting blood flow influences.

Conclusions:

• The posterior trifurcations of the inner carotid artery are a common variant of the Circle of Willis and show a higher propensity for atherosclerosis.
• The presence and degree of atherosclerosis in specific cerebral vessels correlate with their diameter and potential role in brain blood supply.
• These findings highlight the importance of considering individual vascular anatomy in the context of cerebrovascular disease and aging.