Comparative Evaluation of Variations in Cerebral Arterial Circulation on Imaging in Stroke and Non-Stroke Patients

Introduction: This study investigates the variations in cerebral arterial circulation, particularly within the Circle of Willis (CoW), and their association with stroke occurrence. The CoW is an essential arterial network at the base of the brain that facilitates collateral blood flow during arterial blockage. Anatomical variations in this structure, such as hypoplastic or absent arteries, are believed to influence stroke risk. Methods: The study analyzed CoW configurations in a sample of 1,209 stroke and non-stroke patients using non-invasive 3D time-of-flight magnetic resonance angiography (MRA). Patients were categorized based on the presence or absence of ischemic or hemorrhagic stroke as observed on MRA. Results: Significant associations were found between an incomplete CoW configuration and the presence of stroke. Specific variations, including hypoplastic middle cerebral artery (MCA) and A1 segments, were notably more prevalent among stroke patients, suggesting a link with increased stroke risk. In contrast, the fetal posterior cerebral artery (PCA) variation was more common in non-stroke patients, potentially indicating a less harmful role. Conclusion: The findings highlight the importance of evaluating CoW variations for stroke risk assessment. The use of 3D-TOF MRA provides a valuable non-invasive approach for identifying high-risk individuals. This study contributes critical insights for early identification and improved management strategies for individuals with elevated stroke susceptibility. Keywords: Circle of Willis, stroke, magnetic resonance angiography, cerebral arterial variations