Biomechanical Investigation of Disturbed Hemodynamics-Induced Tissue Degeneration in Abdominal Aortic Aneurysms Using Computational and Experimental Techniques

Download
2019-05-31
Salman, Huseyin Enes
Ramazanlı, Burcu
Yavuz, Mehmet Metin
Yalcin, Huseyin Cagatay
Abdominal aortic aneurysm (AAA) is the dilatation of the aorta beyond 50% of the normal vessel diameter. It is reported that 4-8% of men and 0.5-1% of women above 50 years of age bear an AAA and it accounts for similar to 15,000 deaths per year in the United States alone. If left untreated, AAA might gradually expand until rupture; the most catastrophic complication of the aneurysmal disease that is accompanied by a striking overall mortality of 80%. The precise mechanisms leading to AAA rupture remains unclear. Therefore, characterization of disturbed hemodynamics within AAAs will help to understand the mechanobiological development of the condition which will contribute to novel therapies for the condition. Due to geometrical complexities, it is challenging to directly quantify disturbed flows for AAAs clinically. Two other approaches for this investigation are computational modeling and experimental flow measurement. In computational modeling, the problem is first defined mathematically, and the solution is approximated with numerical techniques to get characteristics of flow. In experimental flow measurement, once the setup providing physiological flow pattern in a phantom geometry is constructed, velocity measurement system such as particle image velocimetry (PIV) enables characterization of the flow. We witness increasing number of applications of these complimentary approaches for AAA investigations in recent years. In this paper, we outline the details of computational modeling procedures and experimental settings and summarize important findings from recent studies, which will help researchers for AAA investigations and rupture mechanics.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY

Suggestions

Experimental investigation of hemodynamics in abdominal aortic aneurysm
Fathipour, Amirhossein; Yavuz, Mehmet Metin; Department of Mechanical Engineering (2022-9)
Abdominal aortic aneurysm (AAA), the enduring enlargement of the aorta, is a serious clinical condition with a very high mortality rate when it ruptures. Even though the precise causes of the dilation and rupture mechanisms of the aorta are still unknown, flow-related structures inside the AAA, including vortex formations and wall shear stresses, are associated with these mechanisms. The present study aims to characterize the flow patterns and their evolutions in two aneurysm models, simplified elliptic geo...
Characterization of wall shear stress in abdominal aortic aneurysm phantom using particle image velocimetry
Türk, Semih; Yavuz, Mehmet Metin; Department of Mechanical Engineering (2021-9)
Abdominal Aortic Aneurysm (AAA) is defined as the enlargement of the largest artery in the abdominal cavity, the abdominal aorta. The vascular rupture begins to pose a risk after a certain enlargement, and the rupture is described as one of the most critical emergencies in medicine. The disease is labeled as the 14th disease with the highest mortality rate. Thus, predicting the progression of the disease is vitally important. Hence, researchers are trying to identify and standardize all biological and mecha...
Growth model for abdominal aortic aneurysms using longitudinal CT images
Akkoyun, Emrah; Acar, Aybar Can; Department of Health Informatics (2020)
An Abdominal Aortic Aneurysm (AAA) is diagnosed by an enlargement of the abdominal aorta. The rupture of an AAA, associated with high mortality, is eventually observed if no surgical intervention is performed. Aneurysm repair prior to rupture is thus vital. The decision to intervene is made primarily based on the AAA size measured by a maximum diameter or its growth rate. However, 10 – 24% of aneurysms below the intervention threshold experience rupture in some series. There are many complex interactions in...
Characterization of vortex ring in abdominal aortic aneurysm phantom using particle image velocimetry
Gökçek, Kerem Tuğ; Yavuz, Mehmet Metin; Department of Mechanical Engineering (2021-9)
Abdominal aortic aneurysm (AAA) is the permanent enlargement of the abdominal artery that may even rupture at the end, and it is a critical medical situation with a high mortality rate. Although there are some approaches to model its enlargement and rupture, a complete understanding is far from over. A vortex ring is generated during physiological flow pattern, and its evolution should be analyzed in detail to understand its effect on the flow field. The aim of this study is to investigate and characterize ...
SIMULATION OF ANEURYSM HEMODYNAMICS TO PREDICT INTRALUMINAL THROMBUS FORMATION REGION
RAMAZANLI, BURCU; Yavuz, Mehmet Metin; Sert, Cüneyt; Department of Mechanical Engineering (2022-12-02)
Intraluminal thrombus (ILT) is a fibrin structure which might affect rupture characteristics and be observed 80% of abdominal aortic aneurysms (AAA). Disturbed hemodynamics inside AAA might affect ILT formation, that are generally quantified by wall shear stress (WSS) parameters in literature. Together with WSS parameters, vortex structures observed inside arterial systems can also be counted as indicators of disturbed hemodynamics, and might contribute the generation of ILT. To understand the effect of dis...
Citation Formats
H. E. Salman, B. Ramazanlı, M. M. Yavuz, and H. C. Yalcin, “Biomechanical Investigation of Disturbed Hemodynamics-Induced Tissue Degeneration in Abdominal Aortic Aneurysms Using Computational and Experimental Techniques,” FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/36699.