Abstract：
BACKGROUND: Recently, computational fluid dynamics (CFD) has been used to simulate blood flow of symptomatic intracranial atherosclerotic stenosis (sICAS) and investigate the clinical implications of its haemodynamic features, which were systematically reviewed in this study.
METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology statements, we searched PubMed and Embase up to March 2024 and screened for articles reporting clinical implications of haemodynamic parameters in sICAS derived from CFD models.
RESULTS: 19 articles met the inclusion criteria, all studies recruiting patients from China. Most studies used CT angiography (CTA) as the source image for vessel segmentation, and generic boundary conditions, rigid vessel wall and Newtonian fluid assumptions for CFD modelling, in patients with 50%-99% sICAS. Pressure and wall shear stress (WSS) were quantified in almost all studies, and the translesional changes in pressure and WSS were usually quantified with a poststenotic to prestenotic pressure ratio (PR) and stenotic-throat to prestenotic WSS ratio (WSSR). Lower PR was associated with more severe stenosis, better leptomeningeal collaterals, prolonged perfusion time and internal borderzone infarcts. Higher WSSR and other WSS measures were associated with positive vessel wall remodelling, regression of luminal stenosis and artery-to-artery embolism. Lower PR and higher WSSR were both associated with the presence and severity of cerebral small vessel disease. Moreover, translesional PR and WSSR were promising predictors for stroke recurrence in medically treated patients with sICAS and outcomes after acute reperfusion therapy, which also provided indicators to assess the effects of stenting treatment on focal haemodynamics.
CONCLUSIONS: CFD is a promising tool in investigating the pathophysiology of ICAS and in risk stratification of patients with sICAS. Future studies are warranted for standardisation of the modelling methods and validation of the simulation results in sICAS, for its wider applications in clinical research and practice.
METHODS: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology statements, we searched PubMed and Embase up to March 2024 and screened for articles reporting clinical implications of haemodynamic parameters in sICAS derived from CFD models.
RESULTS: 19 articles met the inclusion criteria, all studies recruiting patients from China. Most studies used CT angiography (CTA) as the source image for vessel segmentation, and generic boundary conditions, rigid vessel wall and Newtonian fluid assumptions for CFD modelling, in patients with 50%-99% sICAS. Pressure and wall shear stress (WSS) were quantified in almost all studies, and the translesional changes in pressure and WSS were usually quantified with a poststenotic to prestenotic pressure ratio (PR) and stenotic-throat to prestenotic WSS ratio (WSSR). Lower PR was associated with more severe stenosis, better leptomeningeal collaterals, prolonged perfusion time and internal borderzone infarcts. Higher WSSR and other WSS measures were associated with positive vessel wall remodelling, regression of luminal stenosis and artery-to-artery embolism. Lower PR and higher WSSR were both associated with the presence and severity of cerebral small vessel disease. Moreover, translesional PR and WSSR were promising predictors for stroke recurrence in medically treated patients with sICAS and outcomes after acute reperfusion therapy, which also provided indicators to assess the effects of stenting treatment on focal haemodynamics.
CONCLUSIONS: CFD is a promising tool in investigating the pathophysiology of ICAS and in risk stratification of patients with sICAS. Future studies are warranted for standardisation of the modelling methods and validation of the simulation results in sICAS, for its wider applications in clinical research and practice.
摘要：
背景：最近，计算流体力学（CFD）已用于模拟症状性颅内动脉粥样硬化性狭窄（sICAS）的血流，并研究其血流动力学特征的临床意义，在这项研究中进行了系统的回顾。
方法：遵循流行病学陈述中观察性研究的系统评价和荟萃分析和荟萃分析的首选报告项目，我们检索了截至2024年3月的PubMed和Embase,筛选了报告来自CFD模型的sICAS血流动力学参数临床意义的文章.
结果：19篇文章符合纳入标准，所有研究都从中国招募患者。大多数研究使用CT血管造影（CTA）作为血管分割的源图像，和通用边界条件，用于CFD建模的刚性血管壁和牛顿流体假设，在50％-99％sICAS患者中。几乎所有研究都对压力和壁面剪应力(WSS)进行了量化，通常用狭窄后与狭窄前的压力比（PR）和狭窄-咽喉与狭窄前的WSS比（WSSR）来量化压力和WSS的转移变化。较低的PR与更严重的狭窄相关，更好的软脑膜络脉，灌注时间延长和内交界区梗死。较高的WSSR和其他WSS措施与积极的血管壁重塑相关，管腔狭窄和动脉-动脉栓塞的消退。较低的PR和较高的WSSR均与脑小血管疾病的存在和严重程度有关。此外，对于接受药物治疗的sICAS患者的卒中复发和急性再灌注治疗后的转归,经病灶PR和WSSR是有前景的预测因子,它还提供了评估支架治疗对局灶性血流动力学影响的指标。
结论：CFD在研究ICAS的病理生理学和sICAS患者的风险分层方面是一个有前景的工具。未来的研究有必要标准化的建模方法和验证sICAS中的模拟结果，在临床研究和实践中的广泛应用。
方法：遵循流行病学陈述中观察性研究的系统评价和荟萃分析和荟萃分析的首选报告项目，我们检索了截至2024年3月的PubMed和Embase,筛选了报告来自CFD模型的sICAS血流动力学参数临床意义的文章.
结果：19篇文章符合纳入标准，所有研究都从中国招募患者。大多数研究使用CT血管造影（CTA）作为血管分割的源图像，和通用边界条件，用于CFD建模的刚性血管壁和牛顿流体假设，在50％-99％sICAS患者中。几乎所有研究都对压力和壁面剪应力(WSS)进行了量化，通常用狭窄后与狭窄前的压力比（PR）和狭窄-咽喉与狭窄前的WSS比（WSSR）来量化压力和WSS的转移变化。较低的PR与更严重的狭窄相关，更好的软脑膜络脉，灌注时间延长和内交界区梗死。较高的WSSR和其他WSS措施与积极的血管壁重塑相关，管腔狭窄和动脉-动脉栓塞的消退。较低的PR和较高的WSSR均与脑小血管疾病的存在和严重程度有关。此外，对于接受药物治疗的sICAS患者的卒中复发和急性再灌注治疗后的转归,经病灶PR和WSSR是有前景的预测因子,它还提供了评估支架治疗对局灶性血流动力学影响的指标。
结论：CFD在研究ICAS的病理生理学和sICAS患者的风险分层方面是一个有前景的工具。未来的研究有必要标准化的建模方法和验证sICAS中的模拟结果，在临床研究和实践中的广泛应用。
