Background/Objectives: Hemodynamic stressors, including abnormal wall shear stress (low or high) or oscillatory shear index are recognized as contributors to the pathogenesis, growth, and rupture of intracranial aneurysms (IAs). Computational fluid dynamics (CFD) has therefore become an essential tool for their quantitative assessment. This systematic review aimed to identify the most frequently analyzed hemodynamic and morphological parameters in recent CFD studies and summarize the methodological strategies employed. Methods: A systematic review was conducted following the PRISMA guidelines, including original studies published between 2019 and 2024 in PubMed, Scopus, Web of Science, and Embase databases. Eligible studies applied CFD to human saccular aneurysms addressing rupture or growth. Exclusion criteria comprised stent-assisted treatments, idealized or phantom models, and non-human or in vitro analyses. Extracted data included study characteristics, CFD software, meshing and solver approaches, and reported parameters. Results: Thirty-five studies met the eligibility criteria. Commercial software predominated across the segmentation, meshing, and solver stages. The most frequently evaluated wall shear stress metrics were the oscillatory shear index (OSI, 91.43%), time-averaged wall shear stress (TAWSS, 71.43%), low shear area ratio (LSAR, 60.00%), normalized wall shear stress (NWSS, 51.43%), and relative residence time (RRT, 45.71%). Morphological parameters such as the aspect ratio (AR, 74.29%), size ratio (SR, 68.57%), and volume (42.86%), reflecting aneurysm shape and relative size, were the most consistently evaluated and demonstrated strong associations with rupture and growth. Conclusions: A core set of morphological and hemodynamic parameters (AR, SR, TAWSS, OSI, RRT, and LSAR) was consistently identified as potential discriminators for the rupture and growth of intracranial aneurysms. However, substantial methodological heterogeneity and the absence of unified standards hinder reproducibility and clinical translation. Future research must urgently standardize computational frameworks, parameter definitions, and boundary conditions to enhance the consistency, comparability, and clinical applicability of CFD in aneurysm risk assessment.

Background: Residual intracranial aneurysms post-clipping or coiling pose a poorly established risk of rupture. Computational fluid dynamic (CFD) offers insights into hemodynamic changes following such interventions. This study aims to assess hemodynamic parameters in residual aneurysms pre- and post-treatment with surgical clips or coils using CFD. Methods: A retrospective analysis of consecutive patients between January 2015 and January 2024 was conducted. Digital subtraction angiography images were reconstructed using 3D modeling techniques, and hemodynamic parameters were analyzed with ANSYS^® software. Results: Six aneurysms were analyzed: Five unruptured and one ruptured. The aneurysms were located at the basilar apex (2), middle cerebral artery bifurcation (2), and origin of the posterior communicating artery (2). Post-treatment, there was a significant reduction in both aneurysm area (median reduction of 33.73%) and volume (median reduction of 25.3%). Five of the six cases demonstrated fewer low wall shear stress (WSS) areas, which could indicate a reduction in regions prone to thrombus formation and diminished risk of rupture. In the unruptured aneurysms, there was a median increase of 137.6% in average WSS. Notably, the only case with increased low WSS area also had the highest increase in average WSS. One basilar artery aneurysm showed increased WSS across all parameters, suggesting a higher rupture risk. Conclusion: The increase in average and high WSS area, along with a decrease in low WSS area, reflects a complex balance between factors of stability and rupture risk. However, a simultaneous increase in all WSS parameters may represent the highest rupture risk due to increased mechanical stress on the aneurysm wall, necessitating closer monitoring.

BACKGROUND AND IMPORTANCE: Basilar artery fenestration aneurysms (BAFAs) present significant clinical challenges because of their high rupture risk and complex anatomy. Comprehensive management strategies are required, including thorough vascular assessment and post-treatment surveillance. Integration of complementary analyses such as computational fluid dynamics (CFD) holds promise in facilitating preoperative planning for these intricate lesions. CLINICAL PRESENTATION: A 60-year-old female was diagnosed with a BAFA during evaluation for headaches. Digital subtraction angiography revealed the aneurysm projecting posteriorly with a neck predominantly based on the right limb of the fenestration. After initial treatment with a pipeline embolization device, the aneurysm remained patent, requiring further treatment. A secondary approach with stent-assisted loose-packing coil embolization was then performed, resulting in complete occlusion of the aneurysm. Analysis of pretreatment 3-dimensional rotational angiogram images with CFD provided critical hemodynamic insights. It identified that 38.89% of the aneurysm area was exposed to low wall shear stress (WSS) and 11.5% was exposed to high WSS, indicating a high rupture risk profile with significant areas of both low and high WSS. In addition, low WSS was observed in regions corresponding to daughter sacs, suggesting a higher rupture risk. Streamline analysis indicated increased inflow through the right vertebral artery and the right limb of the fenestration, supporting the initial angiographic impression and guiding the choice of therapeutic strategy. CONCLUSION: This is the first study to analyze the morphology and pretreatment hemodynamics of a BAFA using CFD, illustrating the potential for future development of individualized therapeutic approach–based CFD in complex aneurysms.