Variations of the Arterial Circle of Willis in Cadavers

The Circle of Willis is the most important route for cerebral perfusion and for collateral blood flow in severe occlusive diseases of the internal carotid artery. The knowledge of ideal configuration is required while determining the adequacy of brain circulation in operations of cerebral aneurysms and ligation of carotid artery. The present study was undertaken to study the arteries forming the Circle of Willis and to note variations in configuration or branching pattern.