Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients

Nwatsock Joseph-Francis; Gharingam Marie Laure; Moulion-Tapouh Jean-Roger; Simoni Paolo; Moifo Boniface

doi:doi:10.11648/j.ijmi.20231101.11

| Peer-Reviewed

Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients

Nwatsock Joseph-Francis, Gharingam Marie Laure, Moulion-Tapouh Jean-Roger, Simoni Paolo, Moifo Boniface

Published in International Journal of Medical Imaging (Volume 11, Issue 1)

Received: 23 November 2022 Accepted: 15 December 2022 Published: 10 January 2023

Views: Downloads:

Download PDF

Share This Article

Twitter
Linked In
Facebook

Abstract

Background and objective: The brain lesions observed in sickle cell patients are often known to be due to vessels occlusions. But other factors could be associated with the genesis of these lesions. The objective of this study was to assess the association between the presence of anatomical variations in the Willis circle and that of brain lesions found on MRI in sickle cell patients. Methods: We conducted a bicentric cross-sectional study with retrolective analysis of images at the medical imaging departments of the HUDERF in Brussels (Belgium) and the Yaoundé General Hospital (Cameroon), over a period of 12 months from November 2020 to October 2021. We included 187 homozygous sickle cell patients with documented electrophoresis and brain MRI results. The MRI were carried out in T1, T2, T2*, FLAIR, Diffusion and 3D TOF sequences on Siemens^® 1.5 Tesla devices. The collected data were analyzed using SPSS^® software version 20.0 for Windows^® with a significant p<0.05. Results: The mean age of patients was 8.76 years with no significant difference between the sexes. Variations in the Willis circle were present in 20 cases (10.70%) with a predominance in the posterior hemicircle (6.96% versus 3.74% for the anterior hemicircle; p=0.04). The most common variation was type G corresponding to hypoplasia or absence of the anterior communicating artery in the anterior hemicircle, and hypoplasia or unilateral absence of a posterior communicating artery in the posterior hemicircle. At the parenchymal level, brain lesions were found in 11 cases (5.88%) including ischemic lesions (3.21%) and leukopathies (1.07%). In general, the existence of these lesions was significantly associated with the presence of the Willis circle variations (p=0.01). Conclusion and recommendation: The presence of anatomical variations of the Willis arterial circle in sickle cell patients is associated with the existence of brain lesions. We therefore conclude that anatomical variations of the Willis circle could be an unknown factor increasing the risk of brain damages and therefore morbidity in these patients. We recommend that a larger sample study be conducted to verify our findings.

Published in	International Journal of Medical Imaging (Volume 11, Issue 1)
DOI	10.11648/j.ijmi.20231101.11
Page(s)	1-5
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2024. Published by Science Publishing Group

Keywords

Anatomical Variations, Willis Circle, Sickle Cell Disease, MRI, Brain Lesions

References

[1]	Ebakisse-Badassou E. L’Organisation internationale de lutte contre la drépanocytose (OILD) et la lutte contre la drépanocytose. Méd Trop 2010; 70 (5): 464-466.
[2]	World Health Organization. Report of the WHO Secretary-General on sickle cell disease. 2010: 6p.
[3]	Mbassi-Awa H, Dongmo F, Ngo-Um S, Mafo-Fonkwo V, Alima-Yanda A. et al. Les crises vaso-occlusives chez les enfants drépanocytaires en milieu hospitalier à Yaoundé. Health Sci Dis 2017; 18 (4): 89-97.
[4]	Lazorthes G, Gouaze A, Santini JJ, Salamon G. The arterial circle of the brain (circulus arteriosus cerebri). Anatomia Clinica 1979; 1: 241-257.
[5]	El Khamlichi A, Azouzi M, Bellakhdar F, Ouhcein A, Lahlaidi A. Anatomic configuration of the circle of Willis in the adult studied by injection technics: a propos of 100 brains. Neurochirurgie 1985; 31 (4): 287-293.
[6]	Eftekhar B, Dadmehr M, Ansari S, Ghodsi M, Nazparvar B, Ketabchi E. Are the distributions of variations of circle of Willis different in different populations? Results of an anatomical study and review of literature. BMC Neurol 2006; 6 (22): 9p. doi.org/10.1186/1471-2377-6-22.
[7]	Hima-maiga A, Ndiaye A, Diallo M, Sakho Y. Cartographie du cercle artériel de la base du cerveau et de ses branches collatérales chez l’africain mélanoderme: à propos de 15 cas d’injection-dissection. JAMO 2014; 7 (3): 33-41.
[8]	Ranil-De-Silva K, Silva R, Amaratunga D, Gunasekera WSL, Jayesekera RW. Types of the cerebral arterial circle (circle of Willis) in a Sri Lankan population. BMC Neurol 2011; 11 (5): 8p. doi.10.1186/1471-2377-11-5.
[9]	Tabzioui R, Boughtoub N, Maaroufi M. Radioanatomie du polygone du Willis. Revue Neurologique 2015; 171 (S1): A134. doi.1016/j.neurol.2015.01.314.
[10]	Papantchev V, Hristov S, Todorova D. Some variations of the circle of Willis, important for cerebral protection in aortic surgery: a study in eastern europeans. Eur J Cardio Thoracic Surg 2007; 31: 982-989.
[11]	Malamateniou C, Adams ME, Srinivasan L, Allsop JM. The anatomic variations of the circle of Willis in preterm and term born infants: an MR angiography study at 3T. Am J Neuroradiol 2009; 30: 1955-1962.
[12]	Kapoor K, Singhand B, Jit Dewan I. Variations in the conﬁguration of the circle of Willis. Anat Sci Int 2008: 83: 96-106.
[13]	Singh R, Kannabathula AB, Sunam H, Deka D. Anatomical variations of circle of Willis - a cadaveric study. Int Surg J 2017; 4 (4): 1249-1258.
[14]	Lancien A, Gibert B, Sadiki H, Benabdellaoui S. Apport de l’IRM dans la drépanocytose de l’enfant. J Radiol 2006; 87 (10): 1483.
[15]	Husson B, Adamsbaum C, Hertz-Pannier L, Renaud C, Chabrier S. Comment l’ARM du polygone de Willis permet une meilleure compréhension des accidents artériels cérébraux (AAC) du nouveau-né à terme. J Neuroradiol 2012; 39 (1): 6.
[16]	Verlhac S, Bernaudin F, Brugières P. Doppler transcrânien chez l’enfant drépanocytaires. J Radiol 2003; 84: 131-138.
[17]	Hsin-Wen Chen, Pao-Sheng Yen, Chau-Chin Lee, Chang-Chi Chen, Pau-Yang Chang. Magnetic resonance angiographic evaluation of circle of Willis in general population: a morphologic study in 507 cases. Chin J Radiol 2004; 29: 223-229.
[18]	Mohamed AM, Ahmed AI. Three-dimensional magnetic resonance angiography of the circle of Willis: anatomical variations in general egyptian population. The Egyp J Radiol Nuclear Med 2011; 42: 405-412.
[19]	Boujlel M, Aloui N, Douira W, Sayed M, Hammou A, Bellagha I. Apport de l’imagerie dans la drépanocytose. J Radiol 2005; 86 (10): 1566.
[20]	Corvesta S, Blaisa B, Dahmania M, De Tersanta A-C, Etienneya A, Maronia C et al. Vasculopathie cérébrale de l’enfant drépanocytaire: points clés et nouveautés. Arch Péd 2018; 25 (1): 63-71.
[21]	Fisher CM. The circle of Willis: anatomical variations. Vasc Dis 1965; 2: 99-105.
[22]	Ramak Hashemi SM, Mahmoodi R, Amirjamshidi A. Variations in the anatomy of the Willis’ circle: a 3-year cross-sectional study from Iran (2006-2009). Are the distributions of variations of circle of Willis different in different populations? Result of an anatomical study and review of literature. Surg Neurol Int 2013; 4 (65): 4p. doi.10.4103/2152-7806.112185.
[23]	Zbair S, Siwane A, Lezar S, Essodegui F. Imagerie du polygone de Willis. J Neuroradiology 2017; 44 (2): 91.
[24]	Gauvrit JY, Carsin-Nicol B, Ferré JC, Le Rumeur E, Carsin M. Du polygone de willis aux capillaires et au-delà, en IRM 3T. J Radiol 2008; 89 (10): 1483.
[25]	Kardile PB, Ughade JM, ViShnuPant Pandit S, Manohar naMdeo Ughad. Anatomical variations of anterior communicating artery. J Clin Diag Res 2013; 7 (12): 2661-2664.
[26]	Hamming AM, Van Walderveen MAA. Mulder IA, Van der Schaaf IC, Kappelle LJ, Velthuis BK. Circle of Willis variations in migraine patients with ischemic stroke. Brain and Behavior 2019; 9: 1-8.
[27]	Jalali Kondori B, Azemati F, Dadseresht S. Magnetic resonance angiographic study of anatomic variations of the circle of Willis in a Population in Tehran. Arch Iran Med 2017; 20 (4): 235-239.
[28]	Saddoud N, Moueddeb S, RemiliImen H, Beya B, Imen G, Mohamed J, Daghfous H. Variantes anatomiques du complexe antérieur du cercle artériel de la base du cerveau: à propos d’un cas de trifurcation de l’artère cérébrale antérieure. J Neuradiol 2017; 44 (2): 89.
[29]	Shaikh R, Sohail S. MRA-based evaluation of anatomical variation of circle of Willis in adult Pakistanis. J Pak Med Assoc 2018; 68 (2): 187-191.
[30]	Niederberger E, Gauvrit J-Y, Morandi X, Carsin-Nicol B, Gauthier T, Ferré J-C. Variantes anatomiques de la partie antérieure du cercle artériel de la base du cerveau en angioscanner multidétecteur. J Neuroradiol 2010; 37 (3): 139-147.
[31]	Nwatsock JF, Guersen J, Diné PE, Biard M, Garcier JM, Boyer L. Acanthiomeatal baseline for temporal bone CT-scan in children: a study of eye lens doses and image quality. Health Sci Dis 2021; 22 (7): 11-16.
[32]	Gunnal S, Farooquı M, Wabale R. Anatomical variability in the termination of the basilar artery in the human cadaveric brain. Turk Neurosurg 2015; 25 (4): 586-589.
[33]	Igbal S. A comprehensive study of the anatomical variations of the circle of Willis in Adult Human Brain. J Clinical Diag Research 2013; 7 (11): 2423-2427.
[34]	Ravikanth R, Philip B. Magnetic resonance angiography determined variations in the circle of Willis: analysis of a large series from a single center. Tzu Chi Med J 2019; 31 (1): 52-59.

Cite This Article

Plain Text BibTeX RIS

APA Style

Nwatsock Joseph-Francis, Gharingam Marie Laure, Moulion-Tapouh Jean-Roger, Simoni Paolo, Moifo Boniface. (2023). Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients. International Journal of Medical Imaging, 11(1), 1-5. https://doi.org/10.11648/j.ijmi.20231101.11

Copy | Download

ACS Style

Nwatsock Joseph-Francis; Gharingam Marie Laure; Moulion-Tapouh Jean-Roger; Simoni Paolo; Moifo Boniface. Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients. Int. J. Med. Imaging 2023, 11(1), 1-5. doi: 10.11648/j.ijmi.20231101.11

Copy | Download

AMA Style

Nwatsock Joseph-Francis, Gharingam Marie Laure, Moulion-Tapouh Jean-Roger, Simoni Paolo, Moifo Boniface. Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients. Int J Med Imaging. 2023;11(1):1-5. doi: 10.11648/j.ijmi.20231101.11

Copy | Download

@article{10.11648/j.ijmi.20231101.11,
  author = {Nwatsock Joseph-Francis and Gharingam Marie Laure and Moulion-Tapouh Jean-Roger and Simoni Paolo and Moifo Boniface},
  title = {Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients},
  journal = {International Journal of Medical Imaging},
  volume = {11},
  number = {1},
  pages = {1-5},
  doi = {10.11648/j.ijmi.20231101.11},
  url = {https://doi.org/10.11648/j.ijmi.20231101.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmi.20231101.11},
  abstract = {Background and objective: The brain lesions observed in sickle cell patients are often known to be due to vessels occlusions. But other factors could be associated with the genesis of these lesions. The objective of this study was to assess the association between the presence of anatomical variations in the Willis circle and that of brain lesions found on MRI in sickle cell patients. Methods: We conducted a bicentric cross-sectional study with retrolective analysis of images at the medical imaging departments of the HUDERF in Brussels (Belgium) and the Yaoundé General Hospital (Cameroon), over a period of 12 months from November 2020 to October 2021. We included 187 homozygous sickle cell patients with documented electrophoresis and brain MRI results. The MRI were carried out in T1, T2, T2*, FLAIR, Diffusion and 3D TOF sequences on Siemens® 1.5 Tesla devices. The collected data were analyzed using SPSS® software version 20.0 for Windows® with a significant pResults: The mean age of patients was 8.76 years with no significant difference between the sexes. Variations in the Willis circle were present in 20 cases (10.70%) with a predominance in the posterior hemicircle (6.96% versus 3.74% for the anterior hemicircle; p=0.04). The most common variation was type G corresponding to hypoplasia or absence of the anterior communicating artery in the anterior hemicircle, and hypoplasia or unilateral absence of a posterior communicating artery in the posterior hemicircle. At the parenchymal level, brain lesions were found in 11 cases (5.88%) including ischemic lesions (3.21%) and leukopathies (1.07%). In general, the existence of these lesions was significantly associated with the presence of the Willis circle variations (p=0.01). Conclusion and recommendation: The presence of anatomical variations of the Willis arterial circle in sickle cell patients is associated with the existence of brain lesions. We therefore conclude that anatomical variations of the Willis circle could be an unknown factor increasing the risk of brain damages and therefore morbidity in these patients. We recommend that a larger sample study be conducted to verify our findings.},
 year = {2023}
}

Copy | Download

TY  - JOUR
T1  - Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients
AU  - Nwatsock Joseph-Francis
AU  - Gharingam Marie Laure
AU  - Moulion-Tapouh Jean-Roger
AU  - Simoni Paolo
AU  - Moifo Boniface
Y1  - 2023/01/10
PY  - 2023
N1  - https://doi.org/10.11648/j.ijmi.20231101.11
DO  - 10.11648/j.ijmi.20231101.11
T2  - International Journal of Medical Imaging
JF  - International Journal of Medical Imaging
JO  - International Journal of Medical Imaging
SP  - 1
EP  - 5
PB  - Science Publishing Group
SN  - 2330-832X
UR  - https://doi.org/10.11648/j.ijmi.20231101.11
AB  - Background and objective: The brain lesions observed in sickle cell patients are often known to be due to vessels occlusions. But other factors could be associated with the genesis of these lesions. The objective of this study was to assess the association between the presence of anatomical variations in the Willis circle and that of brain lesions found on MRI in sickle cell patients. Methods: We conducted a bicentric cross-sectional study with retrolective analysis of images at the medical imaging departments of the HUDERF in Brussels (Belgium) and the Yaoundé General Hospital (Cameroon), over a period of 12 months from November 2020 to October 2021. We included 187 homozygous sickle cell patients with documented electrophoresis and brain MRI results. The MRI were carried out in T1, T2, T2*, FLAIR, Diffusion and 3D TOF sequences on Siemens® 1.5 Tesla devices. The collected data were analyzed using SPSS® software version 20.0 for Windows® with a significant pResults: The mean age of patients was 8.76 years with no significant difference between the sexes. Variations in the Willis circle were present in 20 cases (10.70%) with a predominance in the posterior hemicircle (6.96% versus 3.74% for the anterior hemicircle; p=0.04). The most common variation was type G corresponding to hypoplasia or absence of the anterior communicating artery in the anterior hemicircle, and hypoplasia or unilateral absence of a posterior communicating artery in the posterior hemicircle. At the parenchymal level, brain lesions were found in 11 cases (5.88%) including ischemic lesions (3.21%) and leukopathies (1.07%). In general, the existence of these lesions was significantly associated with the presence of the Willis circle variations (p=0.01). Conclusion and recommendation: The presence of anatomical variations of the Willis arterial circle in sickle cell patients is associated with the existence of brain lesions. We therefore conclude that anatomical variations of the Willis circle could be an unknown factor increasing the risk of brain damages and therefore morbidity in these patients. We recommend that a larger sample study be conducted to verify our findings.
VL  - 11
IS  - 1
ER  -

Copy | Download

Author Information

Nwatsock Joseph-Francis

Faculty of Medicine and Biomedical Sciences (FMSB), The University of Yaounde I, Yaounde, Cameroon
Gharingam Marie Laure

Faculty of Medicine and Biomedical Sciences (FMSB), The University of Yaounde I, Yaounde, Cameroon
Moulion-Tapouh Jean-Roger

Faculty of Medicine and Pharmaceutical Sciences (FMSP), The University of Dschang, Dschang, Cameroon
Simoni Paolo

Department of Radiology and Medical Imaging, The Queen Fabiola Children's University Hospital (HUDERF), Brussels, Belgium
Moifo Boniface

Faculty of Medicine and Biomedical Sciences (FMSB), The University of Yaounde I, Yaounde, Cameroon

Download PDF

Sections

Plain Text BibTeX RIS

APA Style

Nwatsock Joseph-Francis, Gharingam Marie Laure, Moulion-Tapouh Jean-Roger, Simoni Paolo, Moifo Boniface. (2023). Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients. International Journal of Medical Imaging, 11(1), 1-5. https://doi.org/10.11648/j.ijmi.20231101.11

Copy | Download

ACS Style

Nwatsock Joseph-Francis; Gharingam Marie Laure; Moulion-Tapouh Jean-Roger; Simoni Paolo; Moifo Boniface. Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients. Int. J. Med. Imaging 2023, 11(1), 1-5. doi: 10.11648/j.ijmi.20231101.11

Copy | Download

AMA Style

Nwatsock Joseph-Francis, Gharingam Marie Laure, Moulion-Tapouh Jean-Roger, Simoni Paolo, Moifo Boniface. Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients. Int J Med Imaging. 2023;11(1):1-5. doi: 10.11648/j.ijmi.20231101.11

Copy | Download

@article{10.11648/j.ijmi.20231101.11,
  author = {Nwatsock Joseph-Francis and Gharingam Marie Laure and Moulion-Tapouh Jean-Roger and Simoni Paolo and Moifo Boniface},
  title = {Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients},
  journal = {International Journal of Medical Imaging},
  volume = {11},
  number = {1},
  pages = {1-5},
  doi = {10.11648/j.ijmi.20231101.11},
  url = {https://doi.org/10.11648/j.ijmi.20231101.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmi.20231101.11},
  abstract = {Background and objective: The brain lesions observed in sickle cell patients are often known to be due to vessels occlusions. But other factors could be associated with the genesis of these lesions. The objective of this study was to assess the association between the presence of anatomical variations in the Willis circle and that of brain lesions found on MRI in sickle cell patients. Methods: We conducted a bicentric cross-sectional study with retrolective analysis of images at the medical imaging departments of the HUDERF in Brussels (Belgium) and the Yaoundé General Hospital (Cameroon), over a period of 12 months from November 2020 to October 2021. We included 187 homozygous sickle cell patients with documented electrophoresis and brain MRI results. The MRI were carried out in T1, T2, T2*, FLAIR, Diffusion and 3D TOF sequences on Siemens® 1.5 Tesla devices. The collected data were analyzed using SPSS® software version 20.0 for Windows® with a significant pResults: The mean age of patients was 8.76 years with no significant difference between the sexes. Variations in the Willis circle were present in 20 cases (10.70%) with a predominance in the posterior hemicircle (6.96% versus 3.74% for the anterior hemicircle; p=0.04). The most common variation was type G corresponding to hypoplasia or absence of the anterior communicating artery in the anterior hemicircle, and hypoplasia or unilateral absence of a posterior communicating artery in the posterior hemicircle. At the parenchymal level, brain lesions were found in 11 cases (5.88%) including ischemic lesions (3.21%) and leukopathies (1.07%). In general, the existence of these lesions was significantly associated with the presence of the Willis circle variations (p=0.01). Conclusion and recommendation: The presence of anatomical variations of the Willis arterial circle in sickle cell patients is associated with the existence of brain lesions. We therefore conclude that anatomical variations of the Willis circle could be an unknown factor increasing the risk of brain damages and therefore morbidity in these patients. We recommend that a larger sample study be conducted to verify our findings.},
 year = {2023}
}

Copy | Download

TY  - JOUR
T1  - Anatomical Variations of the Willis Circle: A Risk Factor for Brain Lesions in Sickle Cell Patients
AU  - Nwatsock Joseph-Francis
AU  - Gharingam Marie Laure
AU  - Moulion-Tapouh Jean-Roger
AU  - Simoni Paolo
AU  - Moifo Boniface
Y1  - 2023/01/10
PY  - 2023
N1  - https://doi.org/10.11648/j.ijmi.20231101.11
DO  - 10.11648/j.ijmi.20231101.11
T2  - International Journal of Medical Imaging
JF  - International Journal of Medical Imaging
JO  - International Journal of Medical Imaging
SP  - 1
EP  - 5
PB  - Science Publishing Group
SN  - 2330-832X
UR  - https://doi.org/10.11648/j.ijmi.20231101.11
AB  - Background and objective: The brain lesions observed in sickle cell patients are often known to be due to vessels occlusions. But other factors could be associated with the genesis of these lesions. The objective of this study was to assess the association between the presence of anatomical variations in the Willis circle and that of brain lesions found on MRI in sickle cell patients. Methods: We conducted a bicentric cross-sectional study with retrolective analysis of images at the medical imaging departments of the HUDERF in Brussels (Belgium) and the Yaoundé General Hospital (Cameroon), over a period of 12 months from November 2020 to October 2021. We included 187 homozygous sickle cell patients with documented electrophoresis and brain MRI results. The MRI were carried out in T1, T2, T2*, FLAIR, Diffusion and 3D TOF sequences on Siemens® 1.5 Tesla devices. The collected data were analyzed using SPSS® software version 20.0 for Windows® with a significant pResults: The mean age of patients was 8.76 years with no significant difference between the sexes. Variations in the Willis circle were present in 20 cases (10.70%) with a predominance in the posterior hemicircle (6.96% versus 3.74% for the anterior hemicircle; p=0.04). The most common variation was type G corresponding to hypoplasia or absence of the anterior communicating artery in the anterior hemicircle, and hypoplasia or unilateral absence of a posterior communicating artery in the posterior hemicircle. At the parenchymal level, brain lesions were found in 11 cases (5.88%) including ischemic lesions (3.21%) and leukopathies (1.07%). In general, the existence of these lesions was significantly associated with the presence of the Willis circle variations (p=0.01). Conclusion and recommendation: The presence of anatomical variations of the Willis arterial circle in sickle cell patients is associated with the existence of brain lesions. We therefore conclude that anatomical variations of the Willis circle could be an unknown factor increasing the risk of brain damages and therefore morbidity in these patients. We recommend that a larger sample study be conducted to verify our findings.
VL  - 11
IS  - 1
ER  -

Copy | Download