Abstract:
Acute ischemic stroke caused by large vessel occlusions is being increasingly treated with neurovascular interventions. The hemodynamics within the collateral system of the circle of Willis (CoW) hemodynamics play a fundamental role in therapy success. However, transient in vivo data on pathological collateral flow during large vessel occlusions are not available. Moreover, there are no flow models that accurately simulate the hemodynamic conditions in the CoW during large vessel occlusions. We used a circulatory loop to generate highly reproducible cerebrovascular-like flows and pressures and used non-invasive flow visualization and high-resolution flow and pressure measurements to acquire detailed, time-dependent hemodynamics inside an anatomical phantom of the CoW. After calibrating a physiological reference case, we induced occlusions in the 1. middle cerebral artery, 2. terminal carotid artery, and 3. basilar artery; and measured the left posterior communicating artery flow. Mean arterial pressure and pulse pressure remained unchanged in the different occlusion cases compared to the physiological reference case, while total cerebral flow decreased by up to 19%. In all three occlusion cases, reversed flow was found in the left posterior communicating artery compared to the reference case with different flow magnitudes and pulsatility index values. The experimental results were compared with clinical findings, demonstrating the capability of this realistic cerebrovascular flow setup. This novel cerebrovascular flow setup opens the possibility for investigating different topics of neurovascular interventions under various clinical conditions in controlled preclinical laboratory studies.
摘要:
由大血管闭塞引起的急性缺血性卒中越来越多地通过神经血管介入治疗。Willis循环(CoW)血流动力学的副系统内的血流动力学在治疗成功中起着重要作用。然而,大血管闭塞期间病理性侧支血流的瞬时体内数据不可用.此外,没有准确模拟大血管闭塞期间CoW中的血液动力学条件的流动模型。我们使用循环回路来产生高度可重现的脑血管样流量和压力,并使用非侵入性流量可视化和高分辨率流量和压力测量来获取详细的,CoW解剖体模内的时间依赖性血液动力学。校准生理参考病例后,我们在1中诱导闭塞。大脑中动脉,2.颈动脉终末,and3.基底动脉;并测量左后交通动脉血流。与生理参考病例相比,不同闭塞病例的平均动脉压和脉压保持不变,而总脑流量下降了19%。在所有三个闭塞病例中,与具有不同流量和搏动指数值的参考病例相比,在左后交通动脉中发现了反向流动。将实验结果与临床结果进行比较,展示了这种逼真的脑血管流量设置的能力。这种新颖的脑血管血流设置为在受控的临床前实验室研究中在各种临床条件下研究神经血管干预的不同主题提供了可能性。