Types of the cerebral arterial circle (circle of Willis) in a Sri Lankan population

Related Experiment Video

Updated: Jun 5, 2026

Protocol for Isolating the Mouse Circle of Willis
06:30

Protocol for Isolating the Mouse Circle of Willis

Published on: October 22, 2016

K Ranil D De Silva1, Rukmal Silva, Dhammika Amaratunga

  • 1Department of Anatomy, University of Sri Jayewardenepura, Nugegoda, Sri Lanka. ranilds@sltnet.lk

BMC Neurology
|January 19, 2011
PubMed

Insights

Anatomical variations of the circle of Willis are common across ethnic groups. This study identified 15 known and one new variation in Sri Lankan cadavers, highlighting significant inter-ethnic differences.

Area of Science:

  • Neuroanatomy
  • Vascular Anatomy
  • Human Anatomy

Background:

  • Variations in the circle of Willis (CW) impact collateral circulation and stroke risk.
  • Understanding CW anatomy is crucial for assessing cerebrovascular disease risk.

Purpose of the Study:

  • To investigate anatomical variations of the circle of Willis (CW) in Sri Lankan cadavers.
  • To compare the prevalence of CW variations with international autopsy studies.

Main Methods:

  • External diameters of CW arteries were measured in 225 Sri Lankan adult cadavers.
  • Statistical analyses (chi-squared, correspondence analysis) compared CW variation frequencies across diverse ethnic populations.

Main Results:

  • Fifteen previously described CW variations and one new type were identified.
  • Significant differences in CW variation prevalence were observed between ethnic groups (p < 0.0001).
  • Notable variations included hypoplastic arteries (A1, P1, PcoA) and the anterior communicating artery (AcoA).

Conclusions:

  • Significant intra- and inter-ethnic variations exist in the circle of Willis.
  • Further research is needed with standardized measurement methods and hypoplasia definitions.
Abstract

More Related Videos

A Magnetic Resonance Imaging-based Computational Protocol for Analysis of Plaque Morphology and Hemodynamics in Patients with Carotid Artery Stenosis09:36

A Magnetic Resonance Imaging-based Computational Protocol for Analysis of Plaque Morphology and Hemodynamics in Patients with Carotid Artery Stenosis

Published on: August 12, 2025

Performing Permanent Distal Middle Cerebral with Common Carotid Artery Occlusion in Aged Rats to Study Cortical Ischemia with Sustained Disability09:11

Performing Permanent Distal Middle Cerebral with Common Carotid Artery Occlusion in Aged Rats to Study Cortical Ischemia with Sustained Disability

Published on: February 23, 2016

Related Concept Videos

The Arch of Aorta01:10

The Arch of Aorta

The coronary arteries, originating from the ascending aorta, bifurcate from two sinuses located within the ascending aorta. Positioned just above the aortic semilunar valve, these sinuses house essential aortic baroreceptors and chemoreceptors, crucial for maintaining cardiac function. The left coronary artery and the right coronary artery branch off from the left posterior and anterior aortic sinuses, respectively.
Encircling the heart, the coronary arteries form a ring-like structure before...
Arteries of the Head and Neck01:26

Arteries of the Head and Neck

The human body's intricate network of arteries ensures that every organ system receives the necessary oxygen and nutrients for optimal function. The arterial network in the head and neck region is particularly complex, providing vital blood flow to the brain, eyes, and other critical structures. Prominent arteries in this region include the internal carotid arteries and the vertebral arteries.
The internal carotid arteries supply blood to the anterior portion of the cerebrum. They enter the...
Overview of Systemic Arteries01:11

Overview of Systemic Arteries

The human body is a complex, well-organized machine, and at the heart of its operations lies the circulatory system. This network of blood vessels, which includes systemic arteries, plays a vital role in maintaining life by transporting nutrients, oxygen, and waste products to and from cells throughout the body.
Systemic circulation is the part of the cardiovascular system that carries oxygenated blood away from the heart to the body's tissues and returns deoxygenated blood back to the heart.
Coronary Circulation01:21

Coronary Circulation

The heart, an organ critical to survival, gets nourishment not from the blood it pumps but from a separate circulation system known as coronary circulation. This is the shortest circulation in the body and is responsible for supplying the heart with the nutrients it needs to function effectively.
Coronary circulation begins at the base of the aorta, where two main arteries arise—the left and right coronary arteries. These arteries encircle the heart in the coronary sulcus and supply the...
Anastomoses01:19

Anastomoses

In human anatomy, anastomosis refers to a connection or opening between two things, particularly between blood vessels or other tubular structures. The term is derived from the Greek term 'anastomosis,' which means 'outlet' or 'opening.' This natural network of connections plays a critical role in the survival and functionality of the human body.
Anastomoses can be formed at arterial, venous, and lymphatic vessels.
Arterial Anastomosis: These occur between arteries. They are most common in...