RT Journal Article
SR Electronic
T1 Local Hemodynamic Conditions Associated with Focal Changes in the Intracranial Aneurysm Wall
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 510
OP 516
DO 10.3174/ajnr.A5970
VO 40
IS 3
A1 J.R. Cebral
A1 F. Detmer
A1 B.J. Chung
A1 J. Choque-Velasquez
A1 B. Rezai
A1 H. Lehto
A1 R. Tulamo
A1 J. Hernesniemi
A1 M. Niemela
A1 A. Yu
A1 R. Williamson
A1 K. Aziz
A1 S. Sakur
A1 S. Amin-Hanjani
A1 F. Charbel
A1 Y. Tobe
A1 A. Robertson
A1 J. Frösen
YR 2019
UL http://www.ajnr.org/content/40/3/510.abstract
AB BACKGROUND AND PURPOSE: Aneurysm hemodynamics has been associated with wall histology and inflammation. We investigated associations between local hemodynamics and focal wall changes visible intraoperatively.MATERIALS AND METHODS: Computational fluid dynamics models were constructed from 3D images of 65 aneurysms treated surgically. Aneurysm regions with different visual appearances were identified in intraoperative videos: 1) “atherosclerotic” (yellow), 2) “hyperplastic” (white), 3) “thin” (red), 4) rupture site, and 5) “normal” (similar to parent artery), They were marked on 3D reconstructions. Regional hemodynamics was characterized by the following: wall shear stress, oscillatory shear index, relative residence time, wall shear stress gradient and divergence, gradient oscillatory number, and dynamic pressure; these were compared using the Mann-Whitney test.RESULTS: Hyperplastic regions had lower average wall shear stress (P = .005) and pressure (P = .009) than normal regions. Flow conditions in atherosclerotic and hyperplastic regions were similar but had higher average relative residence time (P = .03) and oscillatory shear index (P = .04) than thin regions. Hyperplastic regions also had a higher average gradient oscillatory number (P = .002) than thin regions. Thin regions had lower average relative residence time (P < .001), oscillatory shear index (P = .006), and gradient oscillatory number (P < .001) than normal regions, and higher average wall shear stress (P = .006) and pressure (P = .009) than hyperplastic regions. Thin regions tended to be aligned with the flow stream, while atherosclerotic and hyperplastic regions tended to be aligned with recirculation zones.CONCLUSIONS: Local hemodynamics is associated with visible focal wall changes. Slow swirling flow with low and oscillatory wall shear stress was associated with atherosclerotic and hyperplastic changes. High flow conditions prevalent in regions near the flow impingement site characterized by higher and less oscillatory wall shear stress were associated with local “thinning” of the wall.avgaverageGONgradient oscillatory numberIAintracranial aneurysmmaxmaximumminminimumOSIoscillatory shear indexPREdynamic pressureRRTrelative residence timeUIAunruptured intracranial aneurysmWSSwall shear stress