AUTHOR=Yao Yunchu , Tong Xin , Mei Yuqian , Yu Fan , Shan Yi , Liu Aihua , Chen Duanduan 

TITLE=Hemodynamic indicators of the formation of tandem intracranial aneurysm based on a vascular restoration algorithm

JOURNAL=Frontiers in Neurology

VOLUME=Volume 13 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/neurology/articles/10.3389/fneur.2022.1010777

DOI=10.3389/fneur.2022.1010777

ISSN=1664-2295

ABSTRACT=Background: The underlying pathophysiological mechanism that leads to the incidence of tandem intracranial aneurysms (IAs) remains unclear. Hemodynamic factors are believed closely related to the IA growth, however, the underlying mechanism to induce the growth sequence in the tandem structure is unknown. 
Methods and results: This study involved five patients with tandem IAs. Aneurysm models were reconstructed based on image datasets. A novel vascular restoration algorithm was proposed to generate the hypothetical geometry of the healthy parent vessel prior to each IA formation in the concatenated structure. To investigate the flow-driven mechanism of IA growth, detailed hemodynamic patterns and morphological features were revealed under various growth sequences of tandem IAs. Potential hemodynamic indicators of IA formation were proposed.
Results: The patient cases were divided into two groups according to the size difference of tandem IAs. In the group with similar size of the tandem IAs, position of the vortex core was associated to the site of the secondary aneurysm; while in the group with significant size difference of the IAs, position with the maximum curvature of the parent vessel plays a significant role in aneurysm formation.
Conclusions: This study preliminarily revealed the key hemodynamic and morphological indicators for the formation of the tandem IAs. The proposed vascular restoration algorithm that provided the pre-aneurysm vasculature might be useful in investigating the flow-driven mechanism of IA growth and thus contributes to the evaluation of the risk of secondary aneurysm formation.