@article{78a7734d7be1475cbab4f05331908f4c,
title = "Regional aneurysm wall enhancement is affected by local hemodynamics: A 7T MRI study",
abstract = "BACKGROUND AND PURPOSE: Aneurysm wall enhancement has been proposed as a biomarker for inflammation and instability. However, the mechanisms of aneurysm wall enhancement remain unclear. We used 7T MR imaging to determine the effect of flow in different regions of the wall. MATERIALS AND METHODS: Twenty-three intracranial aneurysms imaged with 7T MR imaging and 3D angiography were studied with computational fluid dynamics. Local flow conditions were compared between aneurysm wall enhancement and nonenhanced regions. Aneurysm wall enhancement regions were subdivided according to their location on the aneurysm and relative to the inflow and were further compared. RESULTS: On average, wall shear stress was lower in enhanced than in nonenhanced regions (P =.05). Aneurysm wall enhancement regions at the neck had higher wall shear stress gradients (P =.05) with lower oscillations (P =.05) than nonenhanced regions. In contrast, aneurysm wall enhancement regions at the aneurysm body had lower wall shear stress (P =.01) and wall shear stress gradients (P =.008) than nonenhanced regions. Aneurysm wall enhancement regions far from the inflow had lower wall shear stress (P =.006) than nonenhanced regions, while aneurysm wall enhancement regions close to the inflow tended to have higher wall shear stress than the nonenhanced regions, but this association was not significant. CONCLUSIONS: Aneurysm wall enhancement regions tend to have lower wall shear stress than nonenhanced regions of the same aneurysm. Moreover, the association between flow conditions and aneurysm wall enhancement seems to depend on the location of the region on the aneurysm sac. Regions at the neck and close to the inflow tend to be exposed to higher wall shear stress and wall shear stress gradients. Regions at the body, dome, or far from the inflow tend to be exposed to uniformly low wall shear stress and have more aneurysm wall enhancement.",
author = "Sara Hadad and F. Mut and Chung, {B. J.} and Roa, {J. A.} and Robertson, {A. M.} and Hasan, {D. M.} and Samaniego, {E. A.} and Cebral, {J. R.}",
note = "Funding Information: Received June 4, 2020; accepted after revision September 30. From the Departments of Bioengineering and Mechanical Engineering (S.H., F.M., J.R.C.), George Mason University, Fairfax, Virginia; Department of Applied Mathematics and Statistics (B.J.C.), Mountclair State University, Mountclair, New Jersey; Departments of Neurology, Neurosurgery, and Radiology (J.A.R., E.A.S.) and Neurosurgery (D.M.H.), University of Iowa, Iowa City, Iowa; and Department of Mechanical Engineering and Material Science (A.M.R.), University of Pittsburgh, Pittsburgh, Pennsylvania. Drs Cebral and Samaniego should be designated as co-senior authors of this article. This work was supported by the 2019 Brain Aneurysm Research Grant from The Bee Foundation and a Pilot Research Grant from the Society of Vascular and Interventional Neurology, both granted to Dr Samaniego, and it was partially supported by the National Institutes of Health grant R01NS097457, granted to Drs Robertson and Cebral. It was conducted on an MRI instrument funded by the University of Iowa from National Institutes of Health 1S10RR028821-01. Funding Information: Disclosures: Sara Hadad—RELATED: Grant: National Institutes of Health, Comments: research grant.* Fernando Mut—RELATED: Grant: National Institutes of Health*; UNRELATED: Grants/Grants Pending: National Institutes of Health, Philips Healthcare, Comments: research plans.* Edgar A. Samaniego—RELATED: Grant: Bee Foundation/Society of Vascular and Interventional Neurology, Comments: The study was sponsored by research grants from the Bee Foundation and Society of Vascular and Interventional Neurology.* Juan R. Cebral—RELATED: Grant: National Institutes of Health, Comments: research grant*; UNRELATED: Grants/Grants Pending: National Institutes of Health, Philips Healthcare, Comments: research grants.* Anne M. Robertson—RELATED: Grant: National Institutes of Health, National Institutes of Neurological Disorders and Stroke, Comments: 1R01NS097457-01*; UNRELATED: Employment: University of Pittsburgh, Comments: William Kepler Whiteford, Professor of Engineering, Associate Dean for Faculty Development; Grants/Grants Pending: National Institutes of Health, Comments: grants on cerebral aneurysms and the bladder wall, submitted proposals on cerebral aneurysms*; Travel/ Accommodations/Meeting Expenses Unrelated to Activities Listed: support for travel and/or hotel at meetings, Comments: I received some support for following invited talks: 1) Plenary Speaker, Identifying Physical Causes of Failure in the Cerebral Aneurysm Wall, Computational Biomedicine Conference, Institute of Engineering and Technology on Savoy Place, London, England, September 25– 27, 2019. https://www.compbiomed-conference.org/#; 2) Keynote Speaker, Identifying Physical Causes of Failure in Brain Aneurysms, 6th International Conference on Computational and Mathematical Biomedical Engineering (CMBE2019), Tohoku University, Sendai City, Japan, June 10–12, 2019. http://www. compbiomed.net/2019/; 3) Invited Speaker, Identifying Physical Causes of Failure in Brain Aneurysms, 16th Interdisciplinary Cerebrovascular Symposium (ICS 2019), Iowa City, Iowa, April 17–19, 2019, http://ics2019.engineering.uiowa.edu. *Money paid to the institution. Publisher Copyright: {\textcopyright} 2021 American Society of Neuroradiology. All rights reserved.",
year = "2021",
month = mar,
day = "1",
doi = "10.3174/AJNR.A6927",
language = "English",
volume = "42",
pages = "464--470",
journal = "American Journal of Neuroradiology",
issn = "0195-6108",
publisher = "American Society of Neuroradiology",
number = "3",
}