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Original article
Published online: 2020-12-05
Submitted: 2020-10-27
Accepted: 2020-11-17
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Anatomical variations and morphometric properties of the circulus arteriosus cerebri in a cadaveric Malawian population

C. Nyasa1, A. Mwakikunga1, L. H. Tembo1, C. Dzamalala1, A. O. Ihunwo2
DOI: 10.5603/FM.a2020.0142
·
Pubmed: 33330970
Affiliations
  1. Biomedical Sciences Department, Anatomy Division, University of Malawi, College of Medicine, Private Bag 360, Blantyre, Malawi
  2. School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Johannesburg, South Africa

open access

Ahead of Print
ORIGINAL ARTICLES
Published online: 2020-12-05
Submitted: 2020-10-27
Accepted: 2020-11-17

Abstract

Background: Knowledge of the anatomy of the circulus arteriosus cerebri (CAC) is important in understanding its role as an arterial anastomotic structure involved in collateral perfusion and equalization of pressure, and may explain observed variations in neurovascular disease prevalences across populations. This study was aimed at understanding the anatomical configuration and morphometric properties of the CAC in Malawian population. Materials and methods: Brains were collected from 24 recently-deceased black Malawian human cadavers during medico-legal autopsies. Photographs of the CACs were taken using a camera placed at a 30 cm height from the base of the brain. Whole-circle properties and segmental vessel parameters were analyzed using the OSIRIS computer program, paying attention to completeness, typicality, symmetry, and segmental vessel diameters and lengths. Results: 69.57 % of the CACs exhibited the complete-circle configuration. Of these, 37.5 % were typical, representing an overall typicality prevalence of 26.09 %. Vessel asymmetry was observed in 30.43 % of cases. There were 7 cases of vessel aplasia and 12 cases of vessel hypoplasia. The posterior communicating artery (PcoA) was the most variable (with 12 variations), widest (7.67 mm) and longest (27.7 mm) vessel while the anterior communicating artery (AcoA) was the shortest (0.78mm). Both the AcoA and the PcoA were the narrowest vessels (0.67 mm) in this study. CAC variations in Malawian populations appeared to be similar to those observed in diverse populations. Conclusions: Anatomical variations of the circulus arteriosus cerebri exist in Malawian population and should be taken into consideration in clinical practice.

Abstract

Background: Knowledge of the anatomy of the circulus arteriosus cerebri (CAC) is important in understanding its role as an arterial anastomotic structure involved in collateral perfusion and equalization of pressure, and may explain observed variations in neurovascular disease prevalences across populations. This study was aimed at understanding the anatomical configuration and morphometric properties of the CAC in Malawian population. Materials and methods: Brains were collected from 24 recently-deceased black Malawian human cadavers during medico-legal autopsies. Photographs of the CACs were taken using a camera placed at a 30 cm height from the base of the brain. Whole-circle properties and segmental vessel parameters were analyzed using the OSIRIS computer program, paying attention to completeness, typicality, symmetry, and segmental vessel diameters and lengths. Results: 69.57 % of the CACs exhibited the complete-circle configuration. Of these, 37.5 % were typical, representing an overall typicality prevalence of 26.09 %. Vessel asymmetry was observed in 30.43 % of cases. There were 7 cases of vessel aplasia and 12 cases of vessel hypoplasia. The posterior communicating artery (PcoA) was the most variable (with 12 variations), widest (7.67 mm) and longest (27.7 mm) vessel while the anterior communicating artery (AcoA) was the shortest (0.78mm). Both the AcoA and the PcoA were the narrowest vessels (0.67 mm) in this study. CAC variations in Malawian populations appeared to be similar to those observed in diverse populations. Conclusions: Anatomical variations of the circulus arteriosus cerebri exist in Malawian population and should be taken into consideration in clinical practice.

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Keywords

anatomical configuration, neurovascular diseases, posterior communicating artery, anterior communicating artery, circle of Willis, hypoplasia, aplasia, vessel asymmetry, internal carotid artery

About this article
Title

Anatomical variations and morphometric properties of the circulus arteriosus cerebri in a cadaveric Malawian population

Journal

Folia Morphologica

Issue

Ahead of Print

Article type

Original article

Published online

2020-12-05

DOI

10.5603/FM.a2020.0142

Pubmed

33330970

Keywords

anatomical configuration
neurovascular diseases
posterior communicating artery
anterior communicating artery
circle of Willis
hypoplasia
aplasia
vessel asymmetry
internal carotid artery

Authors

C. Nyasa
A. Mwakikunga
L. H. Tembo
C. Dzamalala
A. O. Ihunwo

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