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Category: Volume 06 Issue 04 April 2018
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Title: Normal Variants of Circle of Willis in MR Angiography among Puducherry Population

Authors: Dr K.S.Kaviyavarshini, Dr C. Madhumita, Dr Prashant Moorthy

 DOI:  https://dx.doi.org/10.18535/jmscr/v6i4.106

Abstract

Introduction: Circle of Willis is the great arterial anastomotic ring at the base of the brain and is an important pathway to maintain adequate blood supply to the brain. In case of arterial occlusion, it is the important source of collaterals to the occluded territory. A detailed knowledge of the normal anatomy of circle of Willis, its anomalies and clinical significance helps the neurosurgeon for planning and keeps away from vascular trauma during surgeries.

Materials and Methods: A retrospective study was conducted on 312 patients (188 men and 124 women). 3 dimensional time of flight Magnetic resonance angiogram technique was used. Variations in the Circle of Willis were evaluated.

Results: The findings show that majority of circle showed anomalies. Percentage of complete circle was slightly higher in males and young subjects. Normal variants are more common in anterior part of the circle and the most common normal variant is the absent anterior communicating artery (34%).

Conclusion: Magnetic resonance angiogram is the sensitive technique for detecting the anatomy of Circle of Willis. Variations in anterior circulation may be asymptomatic and may reduce complications. Knowledge of the presence of Circle of Willis and its variants plays an important role in planning of neurological procedures or may be mistaken for pathologies.

Keywords: Anomalies, absent anterior communicating artery, 3-dimensional time of flight.

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Corresponding Author

Dr K.S.Kaviyavarshini

SMVMCH, Puducherry