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Anatomical variations and morphometric properties of the circulus arteriosus cerebri in a cadaveric Malawian population
, 12, 12, 1, 2
Affiliations- Biomedical Sciences Department, Anatomy Division, College of Medicine, University of Malawi, Blantyre, Malawi
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Parktown, Johannesburg, South Africa
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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 equalisation 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 analysed using the OSIRIS computer programme, paying attention to completeness, typicality, symmetry, and segmental vessel diameters and lengths.
Results: The complete-circle configuration was found in 69.57% of the CACs. 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 (0.78 mm). 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 CAC 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 equalisation 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 analysed using the OSIRIS computer programme, paying attention to completeness, typicality, symmetry, and segmental vessel diameters and lengths.
Results: The complete-circle configuration was found in 69.57% of the CACs. 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 (0.78 mm). 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 CAC exist in Malawian population and should be taken into consideration in clinical practice.
Keywords
anatomical configuration, neurovascular diseases, posterior communicating artery, anterior communicating artery, circle of Willis, hypoplasia, aplasia, vessel asymmetry, internal carotid artery
About this articleTitle
Anatomical variations and morphometric properties of the circulus arteriosus cerebri in a cadaveric Malawian population
Journal
Issue
Article type
Original article
Pages
820-826
Published online
2020-12-05
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6796
Article views/downloads
956
DOI
Pubmed
Bibliographic record
Folia Morphol 2021;80(4):820-826.
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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