How aneurysm shape affects occlusion success after flow diverter placement.

Abstract

<h4>Purpose</h4>Flow Diverters (FD) are an established endovascular treatment for intracranial aneurysms, but complete aneurysm occlusion remains a challenge. This study aimed to quantitatively analyze three-dimensional aneurysm morphology and assess its influence on the likelihood of total occlusion after FD placement.<h4>Methods</h4>For this single-centre study we retrospectively included patients with unruptured intracranial aneurysm treated with FD between 2019 and 2022. The study group comprised patients with incomplete occlusion at first follow-up (~ 6 months). The control group, matched for common risk factors, included patients with complete occlusion. Based on 3D reconstructions, we calculated quantitative parameters: mean and entropy of mean and Gaussian curvature, mean and entropy of Writhe number, and Zernike Moment Invariants energy.<h4>Results</h4>Thirty-five patients met study group criteria and 38 were included in the control group. Mean age was 57.6 ± 12.2 years and females comprised 82.9% and 81.6% of the groups, respectively. Incompletely occluded aneurysms showed higher Aspect Ratio (1.34 ± 0.42 vs. 1.29 ± 0.51; p = 0.03) and Size Ratio (1.28 ± 0.28 vs. 1.21 ± 0.28; p = 0.04), greater Gaussian curvature entropy (4.03 ± 0.60 vs. 3.73 ± 0.62; p = 0.03), and higher Zernike Moment Invariants energy (545.6 ± 256.2 vs. 271.6 ± 126.2; p = 0.03). In multivariate logistic regression, Gaussian curvature entropy (OR = 2.06; 95% CI: 1.26-13.71; p = 0.04) and Zernike Moment Invariants energy (OR = 3.02; 95% CI: 1.35-9.19; p = 0.02) were independently associated with incomplete occlusion.<h4>Conclusion</h4>Quantitative descriptors of aneurysm dome morphology, particularly Gaussian curvature entropy and Zernike Moment Invariants energy, may influence the likelihood of complete occlusion following FD placement.