Computational Fluid Dynamics for Cerebral Aneurysms in Clinical Settings

Abstract

Hemodynamics is thought to play an important role in the pathogenesis of cerebral aneurysms and recent development of computer technology makes it possible to simulate blood flow using high-resolution 3D images within several hours. A lot of studies of computational fluid dynamics (CFD) for cerebral aneurysms were reported; therefore, application of CFD for cerebral aneurysms in clinical settings is reviewed in this article.CFD for cerebral aneurysms using a patient-specific geometry model was first reported in 2003 and it has been revealing that hemodynamics brings a certain contribution to understanding aneurysm pathology, including initiation, growth and rupture. Based on the knowledge of the state-of-the-art techniques, this review treats the decision-making process for using CFD in several clinical settings. We introduce our CFD procedure using digital imaging and communication in medicine (DICOM) datasets of 3D CT angiography or 3D rotational angiography. In addition, we review rupture status, hyperplastic remodeling of aneurysm wall, and recurrence of coiled aneurysms using the hemodynamic parameters such as wall shear stress (WSS), oscillatory shear index (OSI), aneurysmal inflow rate coefficient (AIRC), and residual flow volume (RFV).

Commentary: Aneurysm Wall Enhancement Is Associated With Decreased Intrasaccular IL-10 and Morphological Features of Instability

“…21 The authors provide a thoughtful and well-written analysis validating significant correlations of AWE with IA morphology and size as well as inverse intra-aneurysmal IL-10 concentrations in incidental unruptured IAs. 19 These findings, which correlate various known risk factors studied in regard to risk of rupture, provide validity to the potential use of AWE as a marker for rupture, [1][2][3][4][5][6][7][8][9][10][11] although further studies with large sample sizes are certainly needed.…”

“…[1][2][3][4][5][6][7][8][9][10][11] Particular interest in recent studies has focused on hemodynamic stress, aneurysm wall inflammatory pathways, aneurysm dome morphology, and high-resolution vessel wall imaging (HR-VWI). [1][2][3][4][5][6][7][8][9][10][11] The clinical application of such studies has centered on the identification of so-called "high-risk lesions," in hopes that prophylactic treatment of unruptured intracranial aneurysms (IAs) may decrease rates of aSAH and thus increase the proportion of patients who achieve good outcome. [1][2][3][4][5][6][7][8][9][10][11] The flood of literature focusing on individual risk factors has resulted in a statistical heterogeneity and decreased prognostic value of traditional categorization systems.…”

Review of intraluminal optical coherence tomography imaging for cerebral aneurysms

“…Rupture risk reflects a complex interplay of aneurysm factors (size, morphology, location, flow dynamics), patient factors (age, sex, comorbidities, genetics), and beyond (Cebral et al, 2011;Lv et al, 2019). Imaging findings including vessel wall enhancement on MRI (Lv et al, 2019;Staarmann et al, 2019) and computational flow modelling on CT or diagnostic angiogram (Cebral et al, 2011;Ishida et al, 2021) are recent advances in the field of aneurysmal rupture prediction. As suggested above, there is also potential in the use of intraluminal OCT in this realm, however the exact role has yet to be elucidated, and there is a lack of current studies assessing this.…”

“…Frontiers in Photonics frontiersin.org growth and rupture risk (Cebral et al, 2011;Ishida et al, 2021), and contrast stasis (or lack of flow into the aneurysm) immediately following treatment has been found to be predictive of aneurysm healing (O'Kelly et al, 2010). Intraluminal doppler OCT may be able to provide more detailed hemodynamic information regarding aneurysms and aneurysm treatment, however, this technology must first be validated against other flow-measuring modalities and explored further in phantom and animal models.…”

Computational Fluid Dynamics Analysis Features in Aneurysm Development in Rats

“…In particular, it has been reported that both high and low WSS results are associated with aneurysm growth and development. [15][16][17][18][19][20][21][22][23][24][25][26][27][28] The CFD analysis was limited to a partial region, including the aneurysm, and there have been no reports of an analysis of the entire cerebral vasculature of experimental ani-S. Komura et al mals as a single system. There have been reports that CFD analysis was performed on aneurysms that were relatively small and difficult to recognize using magnetic resonance image (MRI), and there have been reports that CFD analysis was performed on aneurysms that were artificially created by interposition bypass in the carotid artery.…”