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

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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

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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), 2023. Published by Science Publishing Group

Keywords

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

References

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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

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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

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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

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@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}
}

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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  -

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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

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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

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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

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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