An intracranial aneurysm is the abnormality of the artery where the enfeeble artery wall emerges into a large bulge like a balloon. As per the reports, 10 to 15 million people in the United States have and are expected to have an intracranial aneurysm. Delay in the treatment can lead to rupture of an aneurysm causing the internal bleeding (Subarachnoid hemorrhage) and as the consequences the sudden death can happen. The explicit etiology and pathology behind the initiation, growth, and rupture of an aneurysm have not been entirely understood. However, the hemodynamics in the human vascular system is considered as a dominant risk parameter. For the treatment of an aneurysm the endovascular coiling process seems to majorly favorable from decades. However, there are still plenty of possibilities of formation of the new aneurysm, atherosclerosis plaque, or vasospasm near the target site arteries. Subsequently, it is important to analyze the hemodynamic behavior changes within the before and post embolization treatment for a better understanding of forthcoming complications. The proposed study was conducted through the fluid-structure interaction based simulation within intracranial aneurysm of before and post embolization treatment 3D models to compare and understand the hemodynamic behaviors. The compliance of the elasticity of the arteries plays a significant role, therefore, for the numerical analysis the hyperelastic material (Mooney-Rivlin) was used for the better visualization and investigation of the hemodynamic characteristics. The acquired results illustrate that the blood flow within an aneurysm sac in the before embolization treatment model observed to be recirculating and helical as well as tend to remain for a longer time. On the other hand, due to the embolization treatment the blood flow within the model observed to be stronger throughout inferior to superior region of the inlet internal carotid artery and divided evenly through both anterior cerebral artery and middle cerebral artery outlets. In both models, the high wall shear stress of 26.2 Pa and wall shear stress gradient were observed at the neck of an aneurysm site which may lead to the initiation of another aneurysm or atherosclerosis plaque. The effective stress and pressure were observed to be higher at the apex and neck of an aneurysm which can lead to the wall remolding of an aneurysm. The proposed study can serve as the benchmark reference in the embolization treatment is not only option to overcome an aneurysm condition but also needs to understand the possible complications after the post embolization treatment.

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