Alvaro Valencia¹

Molecular & Cellular Biomechanics, Vol.1, No.3, pp. 221-232, 2004, DOI:10.3970/mcb.2004.001.221

Abstract Flow dynamics play an important role in the pathogenesis and treatment of intracranial aneurysms. The evaluation of the velocity field in the aneurysm dome and neck is important for the correct placement of endovascular coils, and the temporal and spatial variations of wall shear stress in the aneurysm are correlated with its growth and rupture. This numerical investigation describes the hemodynamic in two models of terminal aneurysm of the basilar artery. Aneurysm models with a aspect ratio of 1.0 and 1.67 were studied. Each model was subject to physiological representative waveform of inflow for a mean Reynolds number of 560.… More >

LINGFENG CHEN^1,2,3, ZHIPENG GAO^1,2,3, BAIMEI LIU^1,2,3, YING LV^1,2,3, MEIWEN AN^1,2,3,*, JILING FENG^4,*

BIOCELL, Vol.42, No.1, pp. 25-34, 2018, DOI:10.32604/biocell.2018.06114

Abstract Arterial characterization of healthy descending thoracic aorta (DTA) is indispensable in determining stress distributions across wall thickness and different regions that may be responsible for aorta inhomogeneous dilation, rupture, and dissection when aneurysm occurs. Few studies have shown the inhomogeneity of DTA along the aorta tree considering changes in circumferential direction. The present study aims to clarify the circumferential regional characterization of DTA. Porcine DTA tissues were tested according to region and orientation using uniaxial tension. For axial test, results show that the difference in circumferential direction was mainly in collagen fiber modulus, where the anterior collagen fiber modulus was… More >

O. Ohta¹, F. Gao¹, T. Matsuzawa²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.7, No.3, pp. 146-150, 2008, DOI:10.3970/icces.2008.007.146

Abstract The aortic disease is 2nd place of the cause of death. If the thoracic part and the dissociation are matched, the aortic aneurysm exceeds 60 percent. The aneurysm decided based on the maximum diameter of the aneurysm from the image of which it takes a picture with CT or MRI etc. as such a diagnostic indicator. The appearance of disease, the development, and the rupture of the arterial hemangioma are thought that the hemodynamics such as intravasculars and vessel walls plays an important role [1,2]. Then, we simulated the aneurysm of descending aorta in consideration of the vessel wall of… More >

Christine M. Scotti¹, Sergio L. Cornejo², Ender A. Finol³

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.1, pp. 41-48, 2007, DOI:10.3970/icces.2007.001.041

Abstract Abdominal aortic aneurysm (AAA) rupture is believed to represent the culmination of a complex vascular mechanism partially driven by the forces exerted on the arterial wall. In the present investigation, we present fully coupled fluid-structure interaction (FSI) and finite element analysis (FEA) computations of a patient-specific AAA model. This work advances previous FSI AAA modeling by including localized intraluminal thrombus and the comparison of FSI- and FEA-predicted wall stress distributions. The FSI transient fluid and wall dynamics resulted in a maximum wall stress 21% higher than that obtained with FEA, demonstrating the importance of modeling blood flow for the assessment… More >

F. Gao¹, D. Tang^2∗, Z. Guo³, Makoto Sakamoto⁴, T. Matsuzawa⁵

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.1, pp. 21-28, 2007, DOI:10.3970/icces.2007.001.021

Abstract Patients with aortic aneurysm, especially aortic arch aneurysm, are prone to aortic dissection. For investigation of the effects of aneurysm and wall stiffness on wall stress distribution, a nonaneurysm arch model as well as an aneurysm arch model was constructed. The fluid structure interaction was implemented in the arch model of aorta. The results show that the stresses are much higher at inflection points in the aneurysm model than in nonaneurysm model, and the stresses at media in stiffened wall are higher than in unstiffened wall. The high composite stress is located at inflection points and is much higher in… More >

Petit Claudie¹, Guignandon Alain², Avril Stéphane^1,*

Molecular & Cellular Biomechanics, Vol.16, No.2, pp. 87-108, 2019, DOI:10.32604/mcb.2019.06415

Abstract The contractile behavior of smooth muscle cells (SMCs) in the aorta is an important determinant of growth, remodeling, and homeostasis. However, quantitative values of SMC basal tone have never been characterized precisely on individual SMCs. Therefore, to address this lack, we developed an in vitro technique based on Traction Force Microscopy (TFM). Aortic SMCs from a human lineage at low passages (4-7) were cultured 2 days in conditions promoting the development of their contractile apparatus and seeded on hydrogels of varying elastic modulus (1, 4, 12 and 25 kPa) with embedded fluorescent microspheres. After complete adhesion, SMCs were artificially detached… More >

Zhen Liu¹, Yan Cai¹, Guo-Zhong Chen², Guang-Ming Lu, Zhi-Yong Li^1,3,*

Molecular & Cellular Biomechanics, Vol.14, No.1, pp. 19-31, 2017, DOI:10.3970/mcb.2017.014.019

Abstract Background: Intracranial aneurysm (IA) can be commonly found in the circle of Willis (CoW), and a higher morbidity of IA is found to be associated with a higher percentage of an incomplete CoW. Hemodynamic factors are believed to play an important role in aneurysm formation. However, how the anatomical variations in CoW lead to hemodynamic difference and what hemodynamic parameters play important roles in aneurysm formation have not been quantified and assessed. Methods and Results: Thirty patients were included and based one computed tomography angiography, they were divided into three groups (10 patients per group): a normal group (normal CoW… More >

K. Y. Volokh^*

Molecular & Cellular Biomechanics, Vol.10, No.2, pp. 107-135, 2013, DOI:10.3970/mcb.2013.010.107

Abstract The application of mechanics to biology – biomechanics – bears great challenges due to the intricacy of living things. Their dynamism, along with the complexity of their mechanical response (which in itself involves complex chemical, electrical, and thermal phenomena) makes it very difficult to correlate empirical data with theoretical models. This difficulty elevates the importance of useful biomechanical theories compared to other fields of engineering. Despite inherent imperfections of all theories, a well formulated theory is crucial in any field of science because it is the basis for interpreting observations. This is all-the-more vital, for instance, when diagnosing symptoms, or… More >

Feng Gao^∗,†, Teruo Matsuzawa^‡, Hiroshi Okada^*

Molecular & Cellular Biomechanics, Vol.9, No.2, pp. 127-140, 2012, DOI:10.3970/mcb.2012.009.127

Abstract Aortic aneurysm is a pathology that involves the enlargement of the aortic diameter and has risk factors including aortic dissection. Aneurysm wrapping and stent placement has been used in the treatment of aneurysms. This study aimed to investigate the biomechanical effects of wrapping and stenting on aneurysm. The three-layered aortic aneurysm were created and fluid structure interaction were simulated in wrapped model and stented model. The results provide quantitative predictions of flow patterns and wall mechanics as well as the effects of wrapping and stenting. More >

J.S. Ren^*

Molecular & Cellular Biomechanics, Vol.7, No.4, pp. 213-224, 2010, DOI:10.3970/mcb.2010.007.213

Abstract Dynamic analysis of an axially stretched arterial wall with collagen fibers distributed in two preferred directions under a suddenly applied constant internal pressure along with the possibility of the formation and rupture of aneurysm are examined within the framework of nonlinear dynamics. A two layer tube model with the fiber-reinforced composite-based incompressible anisotropic hyper-elastic material is employed to model the mechanical behavior of the arterial wall. The maximum amplitudes and the phase diagrams are given by numerical computation of the differential relation. It is shown that the arterial wall undergoes nonlinear periodic oscillation and no aneurysms are formed under the… More >