# Dual Approach for Basilar Artery Fenestration Aneurysm With Insights From Computational Fluid Dynamics

## TL;DR

This paper presents a new treatment approach for a complex brain aneurysm using computational fluid dynamics to guide therapy and improve outcomes.

## Contribution

The study is the first to use computational fluid dynamics to analyze the hemodynamics of a basilar artery fenestration aneurysm before treatment.

## Key findings

- Computational fluid dynamics revealed 38.89% of the aneurysm area had low wall shear stress and 11.5% had high wall shear stress.
- Low wall shear stress in daughter sacs indicated a higher rupture risk.
- Streamline analysis supported treatment decisions by showing increased inflow through the right vertebral artery.

## Abstract

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.

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.

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.