Carotid artery stenosis (CAS) often requires surgical intervention through carotid endarterectomy (CEA) to prevent stroke. Accurate cerebrovascular risk assessments are crucial in CEA, as poor collateral circulation can lead to insufficient interhemispheric blood flow compensation, resulting in ischemic complications. Therefore, understanding perioperative risk determinants is vital. This study aims to determine the impact of compromised circle of Willis (CoW) morphology on inter-hemispheric blood flow, focusing on indices based on intraoperative internal carotid artery stump pulse pressure and backflow patterns. In 80 CAS patients who underwent CEA, preoperative CT angiography for CoW was conducted. Patients were categorized into five subgroups based on their CoW anatomy and three additional groups based on intraoperative internal carotid artery (ICA) stump backflow patterns evaluated by the surgeon. Continuous blood pressure signals, including systolic, diastolic, mean, and pulse pressure values, were recorded during the procedure. The relationship between CoW anatomical variants and the systolic and diastolic segments of the averaged pressure waveforms, particularly diastolic pressure decay, was analyzed. The correlation between CoW anatomy and stump backflow intensity was also examined. Significant variability in ICA stump backflow and pressure values was evident across CoW variants. Patients with compromised CoW morphology exhibited weaker backflow patterns and lower ICA stump pulse pressure values, consistent with impaired interhemispheric blood flow. Notably, ICA stump diastolic pressure decay was consistent across most CoW variant groups, indicating developed collateral circulation in cases with CoW anomalies. Thus, impaired CoW integrity is associated with compromised interhemispheric blood flow indices based on intraoperative ICA stump pulse pressure and backflow patterns during CEA. Integrating intraoperative pulse waveform analysis with preoperative CT angiography provides a more detailed assessment of cerebrovascular risk, guiding the selective use of shunts. This combined approach may improve surgical outcomes and patient safety by identifying patients at increased risk of perioperative neurological events due to CoW anomalies.

颈动脉狭窄 （CAR） 通常需要通过颈动脉内膜切除术 （CEA） 进行手术干预，以防止中风。准确的脑血管风险评估在 CEA 中至关重要，因为侧支循环不良会导致半球间血流补偿不足，从而导致缺血并发症。因此，了解围手术期风险决定因素至关重要。本研究旨在确定受损的 Willis 环 （CoW） 形态对半球间血流的影响，重点关注基于术中颈内动脉残端脉压和回流模式的指标。在 80 例接受 CEA 的 CAS 患者中，进行了 CoW 的术前 CT 血管造影。根据患者的 CoW 解剖结构将患者分为 5 个亚组，根据外科医生评估的术中颈内动脉 （ICA） 残端回流模式将另外 3 个亚组分为 3 个亚组。在手术过程中记录连续血压信号，包括收缩压、舒张压、平均值和脉压值。分析 CoW 解剖变异与平均压力波形的收缩和舒张段之间的关系，特别是舒张压衰减。还检查了 CoW 解剖结构与残端回流强度之间的相关性。ICA 残端回流和压力值的显着变化在 CoW 变体中很明显。CoW 形态受损的患者表现出较弱的回流模式和较低的 ICA 残端脉压值，与半球间血流受损一致。值得注意的是，ICA 残端舒张压衰减在大多数 CoW 变体组中是一致的，表明在 CoW 异常的情况下发生了侧支循环。 因此，CoW 完整性受损与基于 CEA 期间 ICA 残端脉搏压和回流模式的半球间血流指数受损有关。将术中脉搏波形分析与术前 CT 血管造影相结合，可更详细地评估脑血管风险，指导选择性使用分流器。这种联合方法可以通过识别因 CoW 异常导致围手术期神经系统事件风险增加的患者来改善手术结果和患者安全。