Hemodynamics in Ruptured Intracranial Aneurysms

Incidental detection of unruptured intracranial aneurysms (UIA) has increased in the recent years. There is a need in the clinical community to identify those that are prone to rupture and would require preventive treatment. Hemodynamics in cerebral blood vessels plays a key role in the lifetime cycle of intracranial aneurysms (IA). Understanding their initiation, growth, and rupture or stabilization may identify those hemodynamic features that lead to aneurysm instability and rupture. Modeling hemodynamics using computational fluid dynamics (CFD) could aid in understanding the processes in the development of IA. The neurosurgical approach during operation of IA allows direct visualization of the aneurysm sac and its sampling in many cases. Detailed analysis of the quality of the aneurysm wall under the microscope, together with histological assessment of the aneurysm wall and CFD modeling, can help in building complex knowledge on the relationship between the biology of the wall and hemodynamics. Detailed CFD analysis of the rupture point can further strengthen the association between hemodynamics and rupture. In this chapter we summarize current knowledge on CFD and intracranial aneurysms

Computational Fluid Dynamic Simulation of Intracranial Aneurysms : analysis of time-depend changes of hemodynamic parameters - the road to clinical use

Matematické modelování hemodynamiky u mozkových aneurysmat Analýza změn parametrů hemodynamiky v čase - cesta ke klinickému využití Hemodynamika se podílí na vzniku intrakraniálního aneurysmatu a změny v jejích parametrech v čase vedou k růstu, stabilizaci nebo ruptuře aneurysmatu. Definování těchto změn pomocí matematického modelování hemodynamiky by významně přispělo k pochopení vývoje a ruptury aneurysmatu a umožnilo by využití matematických simulací v klinické praxi. V následující práci je matematickým modelováním hemodynamiky analyzováno devět incidentálních aneurysmat. U pěti aneurysmat byl modelován jejich vývoj v čase, který vedl k ruptuře a u čtyř aneurysmat byl popsán vliv hemodynamiky na růst. Největší vliv na růst aneurysmat mělo nízké smykové napětí. S růstem se také zvětšovaly oblasti s nízkým smykovým napětím a oscilačním indexem a růst pokračoval. Naproti tomu remodelace krčku podléhala vysokému smykovému napětí a tlaku. U následně prasklých aneurysmat se významně snižovalo minimální smykové napětí a zvětšovala se oblast s minimálním smykovým napětím. Výsledky naznačily podíl rostoucí oblasti nízkého smykového napětí a snižujícího se smykového napětí na zvyšování rizika ruptury aneurysmatu. K posouzení vývoje aneurysmatu a rizika ruptury aneurysmatu pomocí matematického modelování...Computational Fluid Dynamic Simulation of Intracranial Aneurysms Analysis of time-dependent changes of hemodynamic parameters - the road the clinical use Hemodynamics are involved in the genesis of intracranial aneurysms and time- dependent changes of their parameters lead to aneurysm growth, stabilization or rupture. Definition of these changes using computational fluid hemodynamics could significantly contribute to the understanding of aneurysmal development and rupture and could enable the routine use of mathematical simulations. In this study, computational fluid dynamics were performed for nine incidental aneurysms. Five aneurysms were monitored throughout time and factors leading to aneurysm rupture were analyzed. In four aneurysms the influence of the hemodynamics on the growth was defined. Major growth occurred in areas of low wall shear stress and oscillatory index. These areas increased in size during growth time. Contrary to this, neck shape remodeling occurred in areas with large wall shear stress and pressure. Throughout the follow-up of ruptured aneurysms, the minimal wall shear stress decreased, and the area of low wall shear stress increased significantly. The results indicate that decreasing values of minimal wall shear stress and increasing values of low wall shear stress area...Units out of CUMimofakultní pracovištěSecond Faculty of Medicine2. lékařská fakult

Computational Fluid Dynamic Simulation of Intracranial Aneurysms : analysis of time-depend changes of hemodynamic parameters - the road to clinical use

Computational Fluid Dynamic Simulation of Intracranial Aneurysms Analysis of time-dependent changes of hemodynamic parameters - the road the clinical use Hemodynamics are involved in the genesis of intracranial aneurysms and time- dependent changes of their parameters lead to aneurysm growth, stabilization or rupture. Definition of these changes using computational fluid hemodynamics could significantly contribute to the understanding of aneurysmal development and rupture and could enable the routine use of mathematical simulations. In this study, computational fluid dynamics were performed for nine incidental aneurysms. Five aneurysms were monitored throughout time and factors leading to aneurysm rupture were analyzed. In four aneurysms the influence of the hemodynamics on the growth was defined. Major growth occurred in areas of low wall shear stress and oscillatory index. These areas increased in size during growth time. Contrary to this, neck shape remodeling occurred in areas with large wall shear stress and pressure. Throughout the follow-up of ruptured aneurysms, the minimal wall shear stress decreased, and the area of low wall shear stress increased significantly. The results indicate that decreasing values of minimal wall shear stress and increasing values of low wall shear stress area..