Perspective Study of Anatomical Variations of Circle of Willis – A Magnetic Resonance Imaging Study in North Karnataka Population: A Retrospective Study

  • Jagadeesh Morab S. Nijalingappa Medical College, Bagalkot, Karnataka, India
  • Savita Budi S. Nijalingappa Medical College, Bagalkot, Karnataka, India
Keywords: Aneurysm, Cerebrovascular, Circle of Willis, Internal carotid artery, Karnataka, Stroke

Abstract

Background: Two main arteries that supply to brain originate from circle of Willis (COW). The COW exhibits considerable anatomical variations which have clinical and surgical importance.
Method: Fifty-five healthy volunteers aged between 25 and 50 years were studied by the technique used which was three-dimensional times-of-flight magnetic resonance angiography, only arteries forming the COW are studied. For the purpose of identification, COW is divided into anterior and posterior configuration.
Results: The variations of COW were 9 (39%) hyperplasia of ant. cerebral artery, 5 (21.7%) hypoplasia of post-cerebral arteries, 6 (26%) analogous origin of post-cerebellar artery, and 3 (13%) hypoplasia of post-communicating artery.
Conclusion: Complete anatomical knowledge of COW and its variations such as hypoplasia, attenuation of vessels, and analogous origin is necessary for clinician, neurosurgeon vascular surgeon, and radiologist. This baseline study will enable them for proper diagnose and surgery without fatal outcome.

Author Biographies

Jagadeesh Morab, S. Nijalingappa Medical College, Bagalkot, Karnataka, India

Assistant Professor, Department of Surgery

Savita Budi, S. Nijalingappa Medical College, Bagalkot, Karnataka, India

Assistant Professor, Department of Anatomy

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Figure 1: Circle of Willis magnetic resonance imaging image Figure 3: Anomalous (fetal) origin of posterior cerebral artery
magnetic resonance imaging image
Figure 2: Hypoplastic segments in three different patients.
(a) Volume-rendered (VR) three-dimensional time-of-flight
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Morab and Budi: Perspective Study of Anatomical Variations of Circle of Willis – A Magnetic Resonance Imaging Study in North Karnataka
Population: A Retrospective Study
4 IJSS Journal of Surgery | May-Jun 2021 | Volume 7 | Issue 3
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Published
2021-07-01
Section
Articles