open access

Vol 82, No 1 (2023)
Original article
Submitted: 2021-10-04
Accepted: 2021-11-30
Published online: 2021-12-15
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Circle of Willis: anatomical variations of configuration. A magnetic resonance angiography study

M. Enyedi12, C. Scheau3, R. O. Baz4, A. C. Didilescu5
·
Pubmed: 34966998
·
Folia Morphol 2023;82(1):24-29.
Affiliations
  1. Department of Anatomy, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
  2. “Victor Babes” Centre for Diagnosis and Treatment, Bucharest, Romania
  3. Department of Physiology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
  4. Department of Radiology, County Clinical Emergency Hospital, Constanța, Romania
  5. Department of Embryology, Faculty of Dental Medicine, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania

open access

Vol 82, No 1 (2023)
ORIGINAL ARTICLES
Submitted: 2021-10-04
Accepted: 2021-11-30
Published online: 2021-12-15

Abstract

Background: The main scope of this paper is to investigate the prevalence of the anatomical variants of the circle of Willis (CoW) in the Romanian population through magnetic resonance angiography.
Materials and methods: Magnetic resonance angiography images were obtained for 126 individuals and the configurations of the anterior and posterior CoW were identified, and classified. The prevalence of each variant and the number of complete anterior or posterior parts of the circle were determined.
Results: A classical configuration of the CoW was found in 39 (30.9%) cases. The most common posterior variation was the unilateral absence of a posterior communicating artery (n = 28) while in the anterior circle it was the unilateral absence of the precommunicating segment of an anterior cerebral artery (n = 17). A complete entire CoW was found in 63 cases, while the anterior and posterior parts yielded complete configurations in 108 and 73 cases, respectively. Eight cases did not present complete configurations. A foetal posterior communicating artery was identified unilaterally in 14 cases and bilaterally in 6 cases.
Conclusions: Unilateral variations were the most common changes found in CoW configuration. The correct assessment of the CoW configuration may prove useful in the planning and follow-up of brain surgery and interventional procedures, as well as in estimating the prognosis of patients suffering from stroke or other related cerebral vascular events.

Abstract

Background: The main scope of this paper is to investigate the prevalence of the anatomical variants of the circle of Willis (CoW) in the Romanian population through magnetic resonance angiography.
Materials and methods: Magnetic resonance angiography images were obtained for 126 individuals and the configurations of the anterior and posterior CoW were identified, and classified. The prevalence of each variant and the number of complete anterior or posterior parts of the circle were determined.
Results: A classical configuration of the CoW was found in 39 (30.9%) cases. The most common posterior variation was the unilateral absence of a posterior communicating artery (n = 28) while in the anterior circle it was the unilateral absence of the precommunicating segment of an anterior cerebral artery (n = 17). A complete entire CoW was found in 63 cases, while the anterior and posterior parts yielded complete configurations in 108 and 73 cases, respectively. Eight cases did not present complete configurations. A foetal posterior communicating artery was identified unilaterally in 14 cases and bilaterally in 6 cases.
Conclusions: Unilateral variations were the most common changes found in CoW configuration. The correct assessment of the CoW configuration may prove useful in the planning and follow-up of brain surgery and interventional procedures, as well as in estimating the prognosis of patients suffering from stroke or other related cerebral vascular events.

Get Citation

Keywords

circle of Willis, anatomic variation, magnetic resonance angiography

About this article
Title

Circle of Willis: anatomical variations of configuration. A magnetic resonance angiography study

Journal

Folia Morphologica

Issue

Vol 82, No 1 (2023)

Article type

Original article

Pages

24-29

Published online

2021-12-15

Page views

3821

Article views/downloads

1350

DOI

10.5603/FM.a2021.0134

Pubmed

34966998

Bibliographic record

Folia Morphol 2023;82(1):24-29.

Keywords

circle of Willis
anatomic variation
magnetic resonance angiography

Authors

M. Enyedi
C. Scheau
R. O. Baz
A. C. Didilescu

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