Morphological Variation of Circle of Willis in Nepali Population: A 3D Time-of-Flight Magnetic Resonance Angiography Based Study

Authors

  • Rupesh Sharma Lumbini Medical College and Teaching Hospital, Pravas, Palpa https://orcid.org/0000-0002-3422-6150 (unauthenticated)
  • Sona Pokharel Lumbini Medical College and Teaching Hospital
  • Phanendra Neupane Lumbini Medical College and Teaching Hospital
  • Rituraj Subedi Lumbini Medical College and Teaching Hospital

DOI:

https://doi.org/10.22502/jlmc.v9i1.448

Keywords:

Circle of Willis, Magnetic Resonance Angiography, Time of flight

Abstract

Introduction: The Circle of Willis (COW) is an anatomic ring of vessels located at the base of the brain connecting the anterior and posterior circulation by uniting the internal carotid and vertebrobasilar systems to maintain adequate cerebral perfusion. The importance of detailed information of the COW morphology and integrity in any patient cannot be overemphasized, especially for neurophysicians, neurosurgeons, and interventional neuroradiologists who are considering intervention to the intracranial arteries. This study was conducted to study the variation of COW among the Nepalese population and compare the results with those of other nationalities. Methods: It was a prospective cross-sectional study performed using a 1.5 Tesla MRI machine. Complete anatomical assessment of the COW was done. The anterior and posterior components of COW were defined as per the standard literature and evaluated in detail. Results: A total of 118 patients were studied during the period out of which 75 (63.6%) were males and 43 (36.4%) were females. A morphologically normal COW configuration was found only in 55 (46.6%) cases whereas a variant configuration was present in 63 (53.4%) cases. The most common variation was noted in the posterior communicating artery (PCOM) which was present in 42 (67%) cases. The most common single variation in abnormal COW configuration was absent right PCOM. Conclusion: The morphologic variation of the COW is more common than the normal textbook configuration in the Nepalese population, PCOM being the most commonly involved vessel.

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Author Biographies

  • Rupesh Sharma, Lumbini Medical College and Teaching Hospital, Pravas, Palpa

    Assistant Professor,

    Department of Radiology.

  • Sona Pokharel, Lumbini Medical College and Teaching Hospital

    Lecturer,

    Department of Radiology.

  • Phanendra Neupane, Lumbini Medical College and Teaching Hospital

    Lecturer,

    Department of Radiology.

  • Rituraj Subedi, Lumbini Medical College and Teaching Hospital

    Resident,

    Department of Radiology.

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Published

2021-06-30

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Section

Original Research Article

How to Cite

1.
Morphological Variation of Circle of Willis in Nepali Population: A 3D Time-of-Flight Magnetic Resonance Angiography Based Study. J Lumbini Med Coll [Internet]. 2021 Jun. 30 [cited 2025 Nov. 18];9(1):5 pages. Available from: https://www.jlmc.edu.np/index.php/JLMC/article/view/448

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