THE SURGICAL ANATOMY OF THE CIRCLE OF WILLIS AND CEREBRAL PERFUSION
Abstract
The Circle of Willis is a key arterial anastomotic structure located at the base of the brain, ensuring stable cerebral perfusion and providing essential collateral flow during arterial obstruction. Although traditionally described as a complete arterial ring, anatomical studies reveal that variations are far more common than the classical configuration. These structural differences significantly affect hemodynamic balance, susceptibility to aneurysm development, ischemic risk, and the safety of neurosurgical and endovascular interventions. This article presents an academic overview of the surgical anatomy of the Circle of Willis and examines its role in regulating cerebral blood flow under both physiological and pathological conditions.
Keywords
Circle of Willis; cerebral perfusion; collateral circulation; neurosurgical anatomy; arterial variations; anterior communicating artery; posterior communicating artery; fetal-type posterior cerebral artery; cerebral hemodynamics; intracranial aneurysm.
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