Wall mechanical properties and hemodynamics of unruptured intracranial aneurysms

J. R. Cebral, X. Duan, Bong Jae Chung, C. Putman, K. Aziz, A. M. Robertson

Research output: Contribution to journalArticleResearchpeer-review

Abstract

BACKGROUND AND PURPOSE: Aneurysm progression and rupture is thought to be governed by progressive degradation and weakening of the wall in response to abnormal hemodynamics. Our goal was to investigate the relationship between the intra-aneurysmal hemodynamic conditions and wall mechanical properties in human aneurysms. MATERIALS AND METHODS: A total of 8 unruptured aneurysms were analyzed. Computational fluid dynamics models were constructed from preoperative 3D rotational angiography images. The aneurysms were clipped, and the domes were resected and mechanically tested to failure with a uniaxial testing system under multiphoton microscopy. Linear regression analysis was performed to explore possible correlations between hemodynamic quantities and the failure characteristics and stiffness of the wall. RESULTS: The ultimate strain was correlated negatively to aneurysm inflow rate (P = .021), mean velocity (P = .025), and mean wall shear stress (P = .039). It was also correlated negatively to inflow concentration, oscillatory shear index, and measures of the complexity and instability of the flow; however, these trends did not reach statistical significance. The wall stiffness at high strains was correlated positively to inflow rate (P=.014), mean velocity (P=.008), inflow concentration (P=.04), flow instability (P=.006), flow complexity (P=.019), wall shear stress (P = .002), and oscillatory shear index (P = .004). CONCLUSIONS: In a study of 8 unruptured intracranial aneurysms, ultimate strain was correlated negatively with aneurysm inflow rate, mean velocity, and mean wall shear stress. Wall stiffness was correlated positively with aneurysm inflow rate, mean velocity, wall shear stress, flow complexity and stability, and oscillatory shear index. These trends and the impact of hemodynamics on wall structure and mechanical properties should be investigated further in larger studies.

Original languageEnglish
Pages (from-to)1695-1703
Number of pages9
JournalAmerican Journal of Neuroradiology
Volume36
Issue number9
DOIs
StatePublished - 1 Sep 2015

Fingerprint

Intracranial Aneurysm
Aneurysm
Hemodynamics
Hydrodynamics
Rupture
Microscopy
Linear Models
Angiography
Regression Analysis

Cite this

Cebral, J. R. ; Duan, X. ; Chung, Bong Jae ; Putman, C. ; Aziz, K. ; Robertson, A. M. / Wall mechanical properties and hemodynamics of unruptured intracranial aneurysms. In: American Journal of Neuroradiology. 2015 ; Vol. 36, No. 9. pp. 1695-1703.
@article{2c6143eb19094ff88f3a76231bcbb5ab,
title = "Wall mechanical properties and hemodynamics of unruptured intracranial aneurysms",
abstract = "BACKGROUND AND PURPOSE: Aneurysm progression and rupture is thought to be governed by progressive degradation and weakening of the wall in response to abnormal hemodynamics. Our goal was to investigate the relationship between the intra-aneurysmal hemodynamic conditions and wall mechanical properties in human aneurysms. MATERIALS AND METHODS: A total of 8 unruptured aneurysms were analyzed. Computational fluid dynamics models were constructed from preoperative 3D rotational angiography images. The aneurysms were clipped, and the domes were resected and mechanically tested to failure with a uniaxial testing system under multiphoton microscopy. Linear regression analysis was performed to explore possible correlations between hemodynamic quantities and the failure characteristics and stiffness of the wall. RESULTS: The ultimate strain was correlated negatively to aneurysm inflow rate (P = .021), mean velocity (P = .025), and mean wall shear stress (P = .039). It was also correlated negatively to inflow concentration, oscillatory shear index, and measures of the complexity and instability of the flow; however, these trends did not reach statistical significance. The wall stiffness at high strains was correlated positively to inflow rate (P=.014), mean velocity (P=.008), inflow concentration (P=.04), flow instability (P=.006), flow complexity (P=.019), wall shear stress (P = .002), and oscillatory shear index (P = .004). CONCLUSIONS: In a study of 8 unruptured intracranial aneurysms, ultimate strain was correlated negatively with aneurysm inflow rate, mean velocity, and mean wall shear stress. Wall stiffness was correlated positively with aneurysm inflow rate, mean velocity, wall shear stress, flow complexity and stability, and oscillatory shear index. These trends and the impact of hemodynamics on wall structure and mechanical properties should be investigated further in larger studies.",
author = "Cebral, {J. R.} and X. Duan and Chung, {Bong Jae} and C. Putman and K. Aziz and Robertson, {A. M.}",
year = "2015",
month = "9",
day = "1",
doi = "10.3174/ajnr.A4358",
language = "English",
volume = "36",
pages = "1695--1703",
journal = "American Journal of Neuroradiology",
issn = "0195-6108",
number = "9",

}

Wall mechanical properties and hemodynamics of unruptured intracranial aneurysms. / Cebral, J. R.; Duan, X.; Chung, Bong Jae; Putman, C.; Aziz, K.; Robertson, A. M.

In: American Journal of Neuroradiology, Vol. 36, No. 9, 01.09.2015, p. 1695-1703.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Wall mechanical properties and hemodynamics of unruptured intracranial aneurysms

AU - Cebral, J. R.

AU - Duan, X.

AU - Chung, Bong Jae

AU - Putman, C.

AU - Aziz, K.

AU - Robertson, A. M.

PY - 2015/9/1

Y1 - 2015/9/1

N2 - BACKGROUND AND PURPOSE: Aneurysm progression and rupture is thought to be governed by progressive degradation and weakening of the wall in response to abnormal hemodynamics. Our goal was to investigate the relationship between the intra-aneurysmal hemodynamic conditions and wall mechanical properties in human aneurysms. MATERIALS AND METHODS: A total of 8 unruptured aneurysms were analyzed. Computational fluid dynamics models were constructed from preoperative 3D rotational angiography images. The aneurysms were clipped, and the domes were resected and mechanically tested to failure with a uniaxial testing system under multiphoton microscopy. Linear regression analysis was performed to explore possible correlations between hemodynamic quantities and the failure characteristics and stiffness of the wall. RESULTS: The ultimate strain was correlated negatively to aneurysm inflow rate (P = .021), mean velocity (P = .025), and mean wall shear stress (P = .039). It was also correlated negatively to inflow concentration, oscillatory shear index, and measures of the complexity and instability of the flow; however, these trends did not reach statistical significance. The wall stiffness at high strains was correlated positively to inflow rate (P=.014), mean velocity (P=.008), inflow concentration (P=.04), flow instability (P=.006), flow complexity (P=.019), wall shear stress (P = .002), and oscillatory shear index (P = .004). CONCLUSIONS: In a study of 8 unruptured intracranial aneurysms, ultimate strain was correlated negatively with aneurysm inflow rate, mean velocity, and mean wall shear stress. Wall stiffness was correlated positively with aneurysm inflow rate, mean velocity, wall shear stress, flow complexity and stability, and oscillatory shear index. These trends and the impact of hemodynamics on wall structure and mechanical properties should be investigated further in larger studies.

AB - BACKGROUND AND PURPOSE: Aneurysm progression and rupture is thought to be governed by progressive degradation and weakening of the wall in response to abnormal hemodynamics. Our goal was to investigate the relationship between the intra-aneurysmal hemodynamic conditions and wall mechanical properties in human aneurysms. MATERIALS AND METHODS: A total of 8 unruptured aneurysms were analyzed. Computational fluid dynamics models were constructed from preoperative 3D rotational angiography images. The aneurysms were clipped, and the domes were resected and mechanically tested to failure with a uniaxial testing system under multiphoton microscopy. Linear regression analysis was performed to explore possible correlations between hemodynamic quantities and the failure characteristics and stiffness of the wall. RESULTS: The ultimate strain was correlated negatively to aneurysm inflow rate (P = .021), mean velocity (P = .025), and mean wall shear stress (P = .039). It was also correlated negatively to inflow concentration, oscillatory shear index, and measures of the complexity and instability of the flow; however, these trends did not reach statistical significance. The wall stiffness at high strains was correlated positively to inflow rate (P=.014), mean velocity (P=.008), inflow concentration (P=.04), flow instability (P=.006), flow complexity (P=.019), wall shear stress (P = .002), and oscillatory shear index (P = .004). CONCLUSIONS: In a study of 8 unruptured intracranial aneurysms, ultimate strain was correlated negatively with aneurysm inflow rate, mean velocity, and mean wall shear stress. Wall stiffness was correlated positively with aneurysm inflow rate, mean velocity, wall shear stress, flow complexity and stability, and oscillatory shear index. These trends and the impact of hemodynamics on wall structure and mechanical properties should be investigated further in larger studies.

UR - http://www.scopus.com/inward/record.url?scp=84941347148&partnerID=8YFLogxK

U2 - 10.3174/ajnr.A4358

DO - 10.3174/ajnr.A4358

M3 - Article

VL - 36

SP - 1695

EP - 1703

JO - American Journal of Neuroradiology

JF - American Journal of Neuroradiology

SN - 0195-6108

IS - 9

ER -