Human basilar artery: morphology &amp; variations

Asha Usha Vijayakumar; Manju Sudhakaran; Leelabhai Janaki Yovel; Asha Usha Vijayakumar; Manju Sudhakaran; Leelabhai Janaki Yovel

doi:10.3934/medsci.2020017

AIMS Medical Science

2020, Volume 7, Issue 4: 278-292. doi: 10.3934/medsci.2020017

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Research article

Human basilar artery: morphology & variations

1.
Assistant Professor of Anatomy, Sree Gokulam Medical College and Research Foundation, Venjaramoodu, Thiruvananthapuram, Kerala, India
2.
Associate Professor of Anatomy, Government Medical College, Thiruvananthapuram, Kerala, India
3.
Professor of Anatomy (Retd), Indira Gandhi Government Medical College, Thiruvananthapuram, Kerala, India

Received: 09 July 2020 Accepted: 09 October 2020 Published: 28 October 2020

Introduction Basilar artery is an unpaired medium-sized artery formed by the confluence of right and left vertebral arteries at the pontomedullary junction and extends to the pontomesencephalic junction. It forms the spine of posterior cerebral circulation which is constituted by the vertebrobasilar system and its branches. Normal morphology of the basilar artery forms an essential component of cerebral circulation. The present study aims to measure the level of formation & termination, length, diameter, and angle of formation of the basilar artery. The data presented are relevant to understanding human variations and would be a good anatomical reference for clinicians, anatomists, and medical students. Caliber, length, and angle of bifurcation of the basilar artery help in assessing the feasibility and approach for various surgical procedures and predict cerebro-vascular diseases.
Materials & methods 96 adult human brain specimens were studied. (78 male, 18 female) (Age range: 19–80 y; Average age: 47.66 y). Measurements were taken using Vernier calliper. Data was analysed using Microsoft Excel and SPSS software version 17.
Results The basilar artery was formed by the confluence of two vertebral arteries in all specimens extending from the pontomedullary junction to the pontomesencephalic junction in 2/3^rd of the cases. The left vertebral artery was found to be dominant in 62.5% specimens. The basilar artery showed an average length of 3.1 cm (demonstrating positive correlation with age), average diameter of 3.6–3.9 mm at different levels, and average angle of formation as 65.38° in males and 62.22° in females. Fetal type posterior cerebral artery was noticed in 9.4% cases. 3.1% and 6.3% cases were seen on the right and left sides respectively. Basilar artery fenestration was noted in 2 percent specimens.
Conclusion Basilar artery morphology was studied in 96 human adult cadavers. Basilar artery formation and termination was normal in more than 2/3^rd cases. Variations were noted in its origin, vessel hypoplasia, presence of fenestrations, and fetal patterns. The data obtained from this study are relevant for anatomists, medical students, interventional radiologists, and neurosurgeons.
- morphology,
- basilar artery,
- fenestration,
- fetal PCA
Citation: Asha Usha Vijayakumar, Manju Sudhakaran, Leelabhai Janaki Yovel. Human basilar artery: morphology & variations[J]. AIMS Medical Science, 2020, 7(4): 278-292. doi: 10.3934/medsci.2020017

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Abstract

Introduction Basilar artery is an unpaired medium-sized artery formed by the confluence of right and left vertebral arteries at the pontomedullary junction and extends to the pontomesencephalic junction. It forms the spine of posterior cerebral circulation which is constituted by the vertebrobasilar system and its branches. Normal morphology of the basilar artery forms an essential component of cerebral circulation. The present study aims to measure the level of formation & termination, length, diameter, and angle of formation of the basilar artery. The data presented are relevant to understanding human variations and would be a good anatomical reference for clinicians, anatomists, and medical students. Caliber, length, and angle of bifurcation of the basilar artery help in assessing the feasibility and approach for various surgical procedures and predict cerebro-vascular diseases.

Materials & methods 96 adult human brain specimens were studied. (78 male, 18 female) (Age range: 19–80 y; Average age: 47.66 y). Measurements were taken using Vernier calliper. Data was analysed using Microsoft Excel and SPSS software version 17.

Results The basilar artery was formed by the confluence of two vertebral arteries in all specimens extending from the pontomedullary junction to the pontomesencephalic junction in 2/3^rd of the cases. The left vertebral artery was found to be dominant in 62.5% specimens. The basilar artery showed an average length of 3.1 cm (demonstrating positive correlation with age), average diameter of 3.6–3.9 mm at different levels, and average angle of formation as 65.38° in males and 62.22° in females. Fetal type posterior cerebral artery was noticed in 9.4% cases. 3.1% and 6.3% cases were seen on the right and left sides respectively. Basilar artery fenestration was noted in 2 percent specimens.

Conclusion Basilar artery morphology was studied in 96 human adult cadavers. Basilar artery formation and termination was normal in more than 2/3^rd cases. Variations were noted in its origin, vessel hypoplasia, presence of fenestrations, and fetal patterns. The data obtained from this study are relevant for anatomists, medical students, interventional radiologists, and neurosurgeons.

Acknowledgments

We thank the entire teaching and nonteaching faculty of Department of Forensic Medicine, Government Medical College Thiruvananthapuram for their kind support during the period of this study.

Conflicts of interest

The authors declare there is no conflicts of interest.

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