A Study of Collateral and Morphometric Correlation of Anatomical Variations in the Circle of Willis and Internal Carotid Artery in Acute Stroke in Elderly Subjects

ABSTRACT:BackgroundThe Circle of Willis (CoW) is a great architectural wonder that ensures adequate cerebral perfusion throughcollateral circulation. Anatomical variations in the CoW are common and may influence stroke susceptibilityand outcomes, particularly in elderly populations. Despite global research, limited data exist on theassociation between CoW variations and stroke in the Indian geriatric population.ObjectivesThis case-control observational study aims to assess the association between anatomical variations in theCircle of Willis and internal carotid artery (ICA) with acute stroke in elderly Indian subjects (≥60 years)using Time-of-Flight Magnetic Resonance Angiography (TOF-MRA). Additionally, the study will develop anovel Asymmetry Index (AI) for vessel dominance assessment.MethodsA total of 134 participants (67 cases with stroke and 67 age- and sex-matched controls) aged ≥60 years willbe recruited from Datta Meghe Medical College and JNMC hospitals, Nagpur. TOF-MRA will be used toidentify and classify CoW variations. Morphometric parameters, including vessel diameters, lengths, andasymmetry ratios, will be measured. Statistical analysis will determine associations between anatomicalvariations and stroke occurrence.Expected OutcomesThe study will provide region-specific data on CoW variations in elderly Indians, establish correlationsbetween anatomical variations and stroke risk, and introduce a novel Asymmetry Index for clinicalapplication in stroke risk assessment.