1 Department of Radiology, University Medical Center Utrecht, Utrecht, the Netherlands.
2 Centre for Functional and Diagnostic Imaging and Research, Danish Research Centre for Magnetic Resonance, Copenhagen University Hospital, Hvidovre, Denmark.
J Cereb Blood Flow Metab. 2018 Nov;38(11):2021-2032. doi: 10.1177/0271678X17724027. Epub 2017 Aug 4.
Collateral blood flow plays a pivotal role in steno-occlusive internal carotid artery (ICA) disease to prevent irreversible ischaemic damage. Our aim was to investigate the effect of carotid artery disease upon cerebral perfusion and cerebrovascular reactivity and whether haemodynamic impairment is influenced at brain tissue level by the existence of primary and/or secondary collateral. Eighty-eight patients with steno-occlusive ICA disease and 29 healthy controls underwent MR examination. The presence of collaterals was determined with time-of-flight, two-dimensional phase contrast MRA and territorial arterial spin labeling (ASL) imaging. Cerebral blood flow and cerebrovascular reactivity were assessed with ASL before and after acetazolamide. Cerebral haemodynamics were normal in asymptomatic ICA stenosis patients, as opposed to patients with ICA occlusion, in whom the haemodynamics in both hemispheres were compromised. Haemodynamic impairment in the affected brain region was always present in symptomatic patients. The degree of collateral blood flow was inversely correlated with haemodynamic impairment. Recruitment of secondary collaterals only occurred in symptomatic ICA occlusion patients. In conclusion, both CBF and cerebrovascular reactivity were found to be reduced in symptomatic patients with steno-occlusive ICA disease. The presence of collateral flow is associated with further haemodynamic impairment. Recruitment of secondary collaterals is associated with severe haemodynamic impairment.
侧支循环血流在狭窄性颈内动脉（ICA）疾病中起着关键作用，可防止不可逆的缺血性损伤。我们的目的是研究颈动脉疾病对脑灌注和脑血管反应性的影响，以及原发性和/或继发性侧支循环的存在是否会影响脑实质水平的血液动力学。88 例狭窄性 ICA 疾病患者和 29 例健康对照者接受了磁共振检查。通过时间飞跃、二维相位对比 MRA 和区域性动脉自旋标记（ASL）成像确定侧支的存在。在乙酰唑胺前后用 ASL 评估脑血流和脑血管反应性。与 ICA 闭塞患者相比，无症状 ICA 狭窄患者的脑血流动力学正常，而 ICA 闭塞患者的两个半球的血流动力学都受到影响。在有症状的患者中，受累脑区的血液动力学始终存在损害。侧支循环血流的程度与血液动力学损害呈负相关。仅在有症状的 ICA 闭塞患者中募集继发性侧支循环。总之，在狭窄性 ICA 疾病有症状的患者中，CBF 和脑血管反应性均降低。侧支循环血流的存在与进一步的血液动力学损害有关。继发性侧支循环的募集与严重的血液动力学损害有关。
