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Higher oscillatory shear index is related to aneurysm recanalization after coil embolization in posterior communicating artery aneurysms

  • Original Article - Vascular Neurosurgery - Aneurysm
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Abstract

Background

The recurrence rate of posterior communicating artery (Pcom) aneurysms after endovascular treatment (EVT) is higher than that for aneurysms located in other sites. However, it is still unclear what mechanisms are responsible for the recanalization of cerebral aneurysms. In this investigation, we compared hemodynamic factors related with recanalization of Pcom aneurysms treated by endoluminal coiling using computational fluid dynamics (CFD) with high-resolution three-dimensional digital subtraction angiography images.

Methods

Twenty patients were enrolled. A double-sinogram acquisition was performed with and without contrast injection after coil embolization to get true blood vessel lumen by relatively complementing the first sinogram with the second. Adaptive Cartesian meshing was performed to produce vascular wall objects for CFD simulation. The boundary condition for inlet (ICA) was set for dynamic velocity according to the cardiac cycle (0.8 s). Hemodynamic parameters were recorded at two specific points (branching point of Pcom and residual sac). The peak pressure, peak WSS, and oscillatory shear index (OSI) were recorded and analyzed.

Results

The median age was 61.0 years, and 18 patients (90%) were female. During a median follow-up of 12 months, seven (35%) treated aneurysms showed recanalization. The median aneurysm volume was significantly higher, and aneurysm height and neck sizes were significantly longer in the recanalization group than those in the stable group. At the branching point of the Pcom, the peak pressure, peak WSS, or OSI did not significantly differ between the two groups. The only statistically significant hemodynamic parameter related with recanalization was the OSI at the aneurysm point. Multivariate logistic regression showed that with an increase of 0.01 OSI at the aneurysm point, the odds ratio for the aneurysm recanalization was 1.19.

Conclusions

A higher OSI is related with recanalization after coil embolization for a Pcom aneurysm.

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Abbreviations

EVT:

Endovascular treatment

Pcom:

Posterior communicating artery

WSS:

Wall shear stress

OSI:

Oscillatory shear index

CFD:

Computational fluid dynamic

ICA:

Internal carotid artery

AIC:

Akaike information criterion

WSSG:

Wall shear stress gradient

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Funding

This study was supported by grant no. 02-2015-028 from the Seoul National University Bundang Hospital Research Fund and by grant no. 14-2015-003 from the Seoul National University Bundang Hospital Research Fund.

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Authors and Affiliations

  1. Department of Neurosurgery, Seoul National University Bundang Hospital, 82, Gumi-ro 173 Beon-gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 13620, Republic of Korea

    Tackeun Kim, Chang Wan Oh, Jae Seung Bang, Seung Pil Ban, Si Un Lee, Young Deok Kim & O-Ki Kwon

  2. Department of Neurosurgery, Seoul National University College of Medicine, Seoul, Republic of Korea

    Tackeun Kim, Chang Wan Oh, Jae Seung Bang, Seung Pil Ban, Si Un Lee, Young Deok Kim & O-Ki Kwon

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  1. Tackeun Kim
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  2. Chang Wan Oh
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Contributions

Conceptualization: Tackeun Kim, O-Ki Kwon. Data curation and analysis: Tackeun Kim. Funding acquisition: Tackeun Kim, O-Ki Kwon. Methodology: Tackeun Kim, Chang Wan Oh, Jae Seung Bang, Seung Pil Ban, Young Deok Kim. Project administration: O-Ki Kwon. Writing–original draft: Tackeun Kim. Writing–review and editing: Chang Wan Oh, Jae Seung Bang, Seung Pil Ban, Young Deok Kim, O-Ki Kwon

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Correspondence to O-Ki Kwon.

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This study was approved by the institutional review board of Seoul National University Bundang Hospital (IRB No. B-1509-314-111) and therefore was performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki and its later amendments.

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Kim, T., Oh, C.W., Bang, J.S. et al. Higher oscillatory shear index is related to aneurysm recanalization after coil embolization in posterior communicating artery aneurysms. Acta Neurochir 163, 2327–2337 (2021). https://doi.org/10.1007/s00701-020-04607-z

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