A STUDY ON HEMODYNAMIC PARAMETERS IN VESSEL EXPANSIONS IN BRAIN

This work is devoted to finding a way for the prognosis of aneurysm rupture by employing hemodynamic parameters proved by researchers that have an impact on the growth and rupture of intracranial aneurysms. Wall Shear Stress (WSS) and Energy Loss (EL) are the main hemodynamic parameters which are measured in this work. 3D geometries are made from CT Angiography scan images. Total of 26 patients with well-known aneurysm condition are studied. Including 5 cases selected for simulation. Steady-state simulation of blood flow in the aneurysm is performed and results are used for transient analysis. Pulsatile inflow boundary condition from previous measurements by Pc-MRI technique is used for inlet velocity. Windkessel condition is defined for outflow boundary condition. WSS and EL values are calculated for further analysis. A single procedure is defined for integrating these parameters. After these integrations, all parameters are divided by their corresponding values from specific inlet length. First glances on dimensionless values of WSS and EL showed that unruptured aneurysms will have higher EL in comparison to ruptured ones. But wall shear stress did not show a significant difference between ruptured and unruptured aneurysms. Two different types of growth mechanisms are presented. In first type the WSS value is 3 to 5 times larger than the second type. EL has great value in second type aneurysms. These results will help physicians to predict the condition of the aneurysm and eventually, treatment options can take place only if the risk of aneurysm rupture is high.

Keywords:

Intracranial Aneurysms , Aneurysm Rupture , Hemodynamic Parameters of Aneurysm Rupture , Risk of Aneurysm Rupture