Assessing the risk of intracranial aneurysm rupture using computational fluid dynamics: a pilot study

Area of Science:

• Neurosurgery
• Biomedical Engineering
• Radiology

Background:

• Intracranial aneurysms (IAs) pose a significant risk of rupture, leading to subarachnoid hemorrhage.
• Accurate assessment of IA rupture risk is crucial for clinical decision-making and patient management.

Purpose of the Study:

• To compare hemodynamic and morphological parameters in representative cases of ruptured and unruptured intracranial aneurysms.
• To explore the predictive value of these parameters, including the rupture resemblance score (RRS), in evaluating IA rupture risk.

Main Methods:

• Retrospective analysis of CTA and 3D rotational angiography (3DRA) in 2 patients with 3 IAs.
• Comparison of morphological parameters (SR, AR, θF, θA, UI, EI, NSI) and hemodynamic parameters (OSI, RRT, NWSS) between ruptured and unruptured aneurysms, and before/after rupture.

Main Results:

• In case 1, the ruptured IA exhibited larger morphological parameters (SR, AR, θF, θA, UI, EI, NSI) and higher OSI compared to the unruptured IA. The RRS was also higher for the ruptured aneurysm.
• In case 2, progression to a daughter sac was associated with increased SR, AR, θF, θA, UI, EI, NSI, OSI, and RRT, alongside a significant reduction in NWSS. RRS increased over time.

Conclusions:

• Size ratio (SR) and oscillatory shear index (OSI) may serve as predictive indicators for intracranial aneurysm rupture risk.
• Changes in wall shear stress (WSS) before and after IA rupture warrant further investigation.
• The rupture resemblance score (RRS) demonstrates potential for clinical application in assessing IA rupture risk and informing treatment strategies.