大脑的侧支循环由动脉吻合支构成。在发生急性缺血性卒中（AIS）时，侧支循环能够向血供受损的脑组织提供部分灌注，以维持部分供氧供血。基于计算机断层扫描（CT）及磁共振成像（MRI）的神经影像技术能够提供侧支循环范围和程度信息。当前在静脉溶栓（IVT）治疗的基础上，多项机械取栓（MT）治疗的随机临床试验也获得了成功。这些研究确定了侧支循环是影响再灌注及AIS临床预后的关键因素。本文作者回顾了侧支循环的分级及与AIS预后的相关性、常用的评估方法及评分标准等内容，对有关侧支循环的文献进行综述。

[1] HARTKAMP M J,VAN DER GROND J,VAN EVERDINGEN K J,et al.Circle of Willis collateral flow investigated by magnetic resonance angiography[J].Stroke,1999,30(12):2671-2678.
[2] 祁秀丽.rt-PA早期静脉溶栓联合丁苯酞注射液对脑梗死患者NIHSS评分的影响[J].现代医学,2018,46(12):1392-1395.
[3] BANG O Y,SAVER J L,KIM S J,et al.Collateral flow predicts response to endovascular therapy for acute ischemic stroke[J].Stroke,2011,42(3):693-699.
[4] GERBER J C,PETROVA M,KRUKOWSKI P,et al.Collateral state and the effect of endovascular reperfusion therapy on clinical outcome in ischemic stroke patients[J].Brain Behav,2016,6(9):e513.
[5] LENG X,FANG H,LEUNG T W,et al.Impact of collaterals on the efficacy and safety of endovascular treatment in acute ischaemic stroke:a systematic review and meta-analysis[J].J Neurol Neurosurg Psychiatry,2016,87(5):537-544.
[6] BANG O Y,SAVER J L,KIM S J,et al.Collateral flow averts hemorrhagic transformation after endovascular therapy for acute ischemic stroke[J].Stroke,2011,42(8):2235-2239.
[7] CHUANG Y M,CHAN L,LAI Y J,et al.Configuration of the circle of Willis is associated with less symptomatic intracerebral hemorrhage in ischemic stroke patients treated with intravenous thrombolysis[J].J Crit Care,2013,28(2):166-172.
[8] FLORES A,RUBIERA M,RIBÓ M,et al.Poor Collateral Circulation Assessed by Multiphase Computed Tomographic Angiography Predicts Malignant Middle Cerebral Artery Evolution After Reperfusion Therapies[J].Stroke,2015,46(11):3149-3153.
[9] HWANG Y H,KANG D H,KIM Y W,et al.Impact of time-to-reperfusion on outcome in patients with poor collaterals[J].AJNR Am J Neuroradiol,2015,36(3):495-500.
[10] LIEBESKIND D S,JAHAN R,NOGUEIRA R G,et al.Early arrival at the emergency department is associated with better collaterals,smaller established infarcts and better clinical outcomes with endovascular stroke therapy:SWIFT study[J].J Neurointerv Surg,2016,8(6):553-558.
[11] LIMA F O,FURIE K L,SILVA G S,et al.The pattern of leptomeningeal collaterals on CT angiography is a strong predictor of long-term functional outcome in stroke patients with large vessel intracranial occlusion[J].Stroke,2010,41(10):2316-2322.
[12] LIEBESKIND D S,COTSONIS G A,SAVER J L,et al.Collaterals dramatically alter stroke risk in intracranial atherosclerosis[J].Ann Neurol,2011,69(6):963-974.
[13] MITEFF F,LEVI C R,BATEMAN G A,et al.The independent predictive utility of computed tomography angiographic collateral status in acute ischaemic stroke[J].Brain,2009,132(Pt 8):2231-2238.
[14] CAMPBELL B C,CHRISTENSEN S,TRESS B M,et al.Failure of collateral blood flow is associated with infarct growth in ischemic stroke[J].J Cereb Blood Flow Metab,2013,33(8):1168-1172.
[15] OLIVOT J M,MLYNASH M,INOUE M,et al.Hypoperfusion intensity ratio predicts infarct progression and functional outcome in the DEFUSE 2 Cohort[J].Stroke,2014,45(4):1018-1023.
[16] VON BAUMGARTEN L,THIERFELDER K M,BEYER S E,et al.Early CT perfusion mismatch in acute stroke is not time-dependent but relies on collateralization grade[J].Neuroradiology,2016,58(4):357-365.
[17] BANG O Y,GOYAL M,LIEBESKIND D S.Collateral Circulation in Ischemic Stroke:Assessment Tools and Therapeutic Strategies[J].Stroke,2015,46(11):3302-3309.
[18] 黄家星,林文华,刘丽萍,等.缺血性卒中侧支循环评估与干预中国专家共识[J].中国卒中杂志,2013(4):285-293.
[19] KNAUTH M,VON KUMMER R,JANSEN O,et al.Potential of CT angiography in acute ischemic stroke[J].AJNR Am J Neuroradiol,1997,18(6):1001-1010.
[20] MENON B K,D'ESTERRE C D,QAZI E M,et al.Multiphase CT Angiography:A New Tool for the Imaging Triage of Patients with Acute Ischemic Stroke[J].Radiology,2015,275(2):510-520.
[21] RAYMOND S B,SCHAEFER P W.Imaging Brain Collaterals:Quantification,Scoring,and Potential Significance[J].Top Magn Reson Imaging,2017,26(2):67-75.
[22] KONSTAS A A,WINTERMARK M,LEV M H.CT perfusion imaging in acute stroke[J].Neuroimaging Clin N Am,2011,21(2):215-238.
[23] CHEN H,WU B,LIU N,et al.Using standard first-pass perfusion computed tomographic data to evaluate collateral flow in acute ischemic stroke[J].Stroke,2015,46(4):961-967.
[24] 高慧,谢春明,闫福岭.脑侧支循环建立的影像学评估方法研究进展[J].东南大学学报(医学版),2016,35(3):457-460.
[25] YANG J J,HILL M D,MORRISH W F,et al.Comparison of pre-and postcontrast 3D time-of-flight MR angiography for the evaluation of distal intracranial branch occlusions in acute ischemic stroke[J].AJNR Am J Neuroradiol,2002,23(4):557-567.
[26] FLACKE S,URBACH H,FOLKERS P J,et al.Ultra-fast three-dimensional MR perfusion imaging of the entire brain in acute stroke assessment[J].J Magn Reson Imaging,2000,11(3):250-259.
[27] LYU J,MA N,LIEBESKIND D S,et al.Arterial Spin Labeling Magnetic Resonance Imaging Estimation of Antegrade and Collateral Flow in Unilateral Middle Cerebral Artery Stenosis[J].Stroke,2016,47(2):428-433.
[28] HIGASHIDA R T,FURLAN A J,ROBERTS H,et al.Trial design and reporting standards for intra-arterial cerebral thrombolysis for acute ischemic stroke[J].Stroke,2003,34(8):e109-e137.
[29] SEKER F,POTRECK A,MÖHLENBRUCH M,et al.Comparison of four different collateral scores in acute ischemic stroke by CT angiography[J].J Neurointerv Surg,2016,8(11):1116-1118.
[30] YEO L L,PALIWAL P,LOW A F,et al.How temporal evolution of intracranial collaterals in acute stroke affects clinical outcomes[J].Neurology,2016,86(5):434-441.
[31] TAN B Y,WAN-YEE K,PALIWAL P,et al.Good Intracranial Collaterals Trump Poor ASPECTS (Alberta Stroke Program Early CT Score) for Intravenous Thrombolysis in Anterior Circulation Acute Ischemic Stroke[J].Stroke,2016,47(9):2292-2298.
[32] LU S S,ZHANG X,XU X Q,et al.Comparison of CT angiography collaterals for predicting target perfusion profile and clinical outcome in patients with acute ischemic stroke[J].European Radiology,2019,29(9):4922-4929.