Incomplete circle of Willis as a risk factor for intraoperative ischemic events during carotid endarterectomies performed under regional anesthesia – A prospective case-series

Abstract Background The role of the willisian collaterals during carotid endarterectomies (CEAs) is a debated issue. aim present work was to test whether an incomplete or non-functional circle Willis (CoW) risk factor for ischemic events CEA. Patients and methods CEAs were performed under local anesthesia. considered symptomatic (SY) if neurological signs appeared after cross-clamping phase. In SY patients shunt insertion performed. CoW on CT angiograms (CTa) analyzed offline categorized as (missing hypoplastic collaterals) functional by three neuroradiologists. Near-infrared spectroscopy (NIRS) throughout procedure. Results Based CTa, 67 circles found, 54 asymptomatic (ASY) 13 SY. No complete found among patients. Significant differences could be detected between ASY groups (Chi-square: 6.08; p = 0.013). anterior communicating artery missing in 5/13 cases. There no cases arteries group 32.9; 10 −8 ). A bilateral posterior observed 9/13 9/81 24.4; −7 NIRS had sensitivity 76.9% specificity 74.5% detecting symptoms. Conclusions Collateral ability may CEAs. Further studies should delineate preoperative assessment collateral capacity useful decision-making about use