The Influence of Acquired and Congenital Anatomy of the Circle of Willis on the Development of Ischemic Stroke in Carotid Artery Atherosclerosis

The aim of the study is to optimize the identification of risk factors associated with various acquired and congenital vascular pathologies of the brain that lead to ischemic stroke, based on clinical and neuroimaging studies, in order to improve the treatment and rehabilitation of this category of patients. 320 patients who had experienced ischemic stroke examined and treated. Patients divided into two groups based on the completeness of the Willis circle. Group 1 (190 patients) consisted of patients with an incomplete Willis circle, which was further divided into subgroup 1a, including 158 patients (83.2%) with acquired cases of an incomplete Willis circle, and subgroup 1b, comprising 52 patients with congenital anomalies of the Willis circle. The second group consisted of 110 patients with a closed Circle of Willis who had a history of ischemic stroke. In a comprehensive clinical and neuroimaging study of 320 patients who suffered cerebrovascular accident, anomalies of the Circle of Willis found in 110 patients: anterior trifurcation in 34.6%, posterior trifurcation in 46.2%, and disconnection of the WC associated with the absence of the posterior communicating artery in 15.2% and the anterior communicating artery in 52.2%. Anomalies of the Circle of Willis were associated with other congenital and acquired defects, including hypoplasia of the vertebral arteries, stenosis, or occlusions of the internal carotid artery. Incomplete recovery and persistence of disability during the rehabilitation period, as well as the development of recurrent ischemic stroke, depend on the presence of existing risk factors such as inadequate collateral circulation and impaired function of the WC. Visual assessment of collateral circulation using CT angiography in patients who have suffered a cerebrovascular accident revealed reduced blood flow in the cerebral hemispheres in those with an open WC compared to patients with a closed Circle. Thus, the inadequacy of the WC contributes to decreased collateral circulation and impaired compensation processes in cerebral hemodynamics in this category of patients.