Wall Shear Stress and Gradient at Anterior Communicating Artery in Pulsating Flow

Abstract The aneurysm in the cerebral artery is apt to initiate around the “Circle of Willis”. The anterior communicating artery (ACoA), which composes one of major part of the circle of Willis, is the most predilection artery of the aneurysm. This artery is characterized by a singular geometry. At this artery, two proximal anterior cerebral arteries (A1, confluence) join facing each other. Just at this artery, the flow bifurcates two distal anterior cerebral arteries (A2, bifurcation). Namely, this artery has a function as a bypass channel. Therefore, the flow around the anterior communicating artery would be very unstable. The aneurysm arises around the apex of this artery where the confluent flow collides.

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Wall Shear Stress and Initiation of Aneurysm around Anterior Communicating Artery in Pulsating Flow.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series B ◽

10.1299/kikaib.66.652_3124 ◽

2000 ◽

Vol 66 (652) ◽

pp. 3124-3130

Author(s):

Ryuhei YAMAGUCHI ◽

Susumu KUDO ◽

Hiroyuki YAMANOBE ◽

Mikio NAKASHIMA ◽

Ryota SUGIHARA ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Pulsating Flow ◽

Anterior Communicating Artery ◽

Wall Shear

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Wall shear stress gradient is independently associated with middle cerebral artery aneurysm development: a case-control CFD patient-specific study based on 77 patients

BMC Neurology ◽

10.1186/s12883-021-02251-3 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Mikołaj Zimny ◽

Edyta Kawlewska ◽

Anna Hebda ◽

Wojciech Wolański ◽

Piotr Ładziński ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Middle Cerebral Artery ◽

Cerebral Artery ◽

Case Control ◽

Independent Effect ◽

Patient Specific ◽

Aneurysm Formation ◽

Wall Shear ◽

Mca Aneurysm

Abstract Background Previously published computational fluid dynamics (CFD) studies regarding intracranial aneurysm (IA) formation present conflicting results. Our study analysed the involvement of the combination of high wall shear stress (WSS) and a positive WSS gradient (WSSG) in IA formation. Methods We designed a case-control study with a selection of 38 patients with an unruptured middle cerebral artery (MCA) aneurysm and 39 non-aneurysmal controls to determine the involvement of WSS, oscillatory shear index (OSI), the WSSG and its absolute value (absWSSG) in aneurysm formation based on patient-specific CFD simulations using velocity profiles obtained from transcranial colour-coded sonography. Results Among the analysed parameters, only the WSSG had significantly higher values compared to the controls (11.05 vs − 14.76 [Pa/mm], P = 0.020). The WSS, absWSSG and OSI values were not significantly different between the analysed groups. Logistic regression analysis identified WSS and WSSG as significant co-predictors for MCA aneurysm formation, but only the WSSG turned out to be a significant independent prognosticator (OR: 1.009; 95% CI: 1.001–1.017; P = 0.025). Significantly more patients (23/38) in the case group had haemodynamic regions of high WSS combined with a positive WSSG near the bifurcation apex, while in the control group, high WSS was usually accompanied by a negative WSSG (14/39). From the analysis of the ROC curve for WSSG, the area under the curve (AUC) was 0.654, with the optimal cut-off value −0.37 Pa/mm. The largest AUC was recognised for combined WSS and WSSG (AUC = 0.671). Our data confirmed that aneurysms tend to form near the bifurcation apices in regions of high WSS values accompanied by positive WSSG. Conclusions The development of IAs is determined by an independent effect of haemodynamic factors. High WSS impacts MCA aneurysm formation, while a positive WSSG mainly promotes this process.

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Effect of elasticity on wall shear stress inside cerebral aneurysm at anterior cerebral artery

Technology and Health Care ◽

10.3233/thc-161135 ◽

2016 ◽

Vol 24 (3) ◽

pp. 349-357 ◽

Cited By ~ 11

Author(s):

Lijian Xu ◽

Michiko Sugawara ◽

Gaku Tanaka ◽

Makoto Ohta ◽

Hao Liu ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Cerebral Aneurysm ◽

Cerebral Artery ◽

Anterior Cerebral Artery ◽

Wall Shear

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Evaluation of aneurysm-associated wall shear stress related to morphological variations of circle of Willis using a microfluidic device

Journal of Biomechanics ◽

10.1016/j.jbiomech.2014.11.018 ◽

2015 ◽

Vol 48 (2) ◽

pp. 348-353 ◽

Cited By ~ 16

Author(s):

Seong-Won Nam ◽

Samjin Choi ◽

Youjin Cheong ◽

Yeon-Hee Kim ◽

Hun-Kuk Park

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Microfluidic Device ◽

Circle Of Willis ◽

Morphological Variations ◽

Wall Shear

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Distribution of Mass Transfer Rate and Wall Shear Stress Behind Simple Rectangular Stenosis in Pulsating Flow

Journal of Biomechanical Engineering ◽

10.1115/1.3168339 ◽

1989 ◽

Vol 111 (1) ◽

pp. 47-54 ◽

Cited By ~ 9

Author(s):

R. Yamaguchi

Keyword(s):

Mass Transfer ◽

Shear Stress ◽

Wall Shear Stress ◽

Transfer Rate ◽

Schmidt Number ◽

Fluid Dynamic ◽

Mass Transfer Rate ◽

Pulsating Flow ◽

Flow Through ◽

Wall Shear

The distributions of mass transfer rate and wall shear stress in sinusoidal laminar pulsating flow through a two-dimensional asymmetric stenosed channel have been studied experimentally and numerically. The distributions are measured by the electrochemical method. The measurement is conducted at a Reynolds number of about 150, a Schmidt number of about 1000, a nondimensional pulsating frequency of 3.40, and a nondimensional flow amplitude of 0.3. It is suggested that the deterioration of an arterial wall distal to stenosis may be greatly enhanced by fluid dynamic effects.

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Analysis of Flow and Wall Shear Stress in Curvature Induced Dorsal Aneurysms: Effect of Arterial Curvature

Volume 2: Biomedical and Biotechnology Engineering ◽

10.1115/imece2009-11322 ◽

2009 ◽

Author(s):

Arun Ramu ◽

Guo-Xiang Wang

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Fluid Dynamic ◽

Cerebral Arteries ◽

Cerebral Aneurysms ◽

Morbidity Rate ◽

Mortality And Morbidity ◽

Wall Shear ◽

Primary Velocity ◽

The Impact

Intracranial aneurysms are abnormal enlargement in the walls of cerebral arteries. The rupture of aneurysms is the leading cause of subarachnoid hemorrhage (SAH), with a high mortality and morbidity rate. A majority of saccular cerebral aneurysms occur at sites of arterial bifurcations. However, a good percentage of aneurysms are curvature induced and are found along the cavernous arterial segment. The occurrence of such non branching aneurysms, clinically called dorsal aneurysms, can be related to the increased wall shear stress at the curved arteries. The rupture of aneurysms usually occurs at the dome region, which is subjected to reduced wall shear stress (wss) owing to low re-circulating flow. Hence it is important to understand the impact of arterial curvature on the WSS distribution along the dome of aneurysms. Previously, studies have not taken into account the aspect of low WSS along the dome region. In the present 3-d computational fluid dynamic approach, we investigate the impact of varying arterial curvature on spherical dorsal aneurysms. The primary velocity patterns, the WSS distribution along the dome of the aneurysm and the area of increased WSS have been quantified for steady flow conditions.

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