1. Consideration of stiffness of wall layers is decisive for patient-specific analysis of carotid artery with atheroma
- Author
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Jiří Burša, Tomáš Novotný, Aneta Malá, Zdeněk Bednařík, and Ondřej Lisický
- Subjects
Patient-Specific Modeling ,STRESS ,FIBROUS CAP THICKNESS ,02 engineering and technology ,030204 cardiovascular system & hematology ,Vascular Medicine ,Biochemistry ,Stiffness ,Diagnostic Radiology ,0302 clinical medicine ,Medicine and Health Sciences ,INTACT ,Anisotropy ,IN-VIVO ,Multidisciplinary ,Radiology and Imaging ,Physics ,Fibrous cap ,Models, Cardiovascular ,Patient specific ,Condensed Matter Physics ,Magnetic Resonance Imaging ,Lipids ,Plaque, Atherosclerotic ,Finite element method ,Biomechanical Phenomena ,Atheromas ,In Vivo Imaging ,Carotid Arteries ,medicine.anatomical_structure ,Physical Sciences ,Medicine ,Anatomy ,medicine.symptom ,Research Article ,STRAIN ,Histology ,Materials science ,Imaging Techniques ,Science ,Materials Science ,Material Properties ,Finite Element Analysis ,0206 medical engineering ,Research and Analysis Methods ,Stress (mechanics) ,03 medical and health sciences ,Diagnostic Medicine ,medicine ,Mechanical Properties ,Humans ,Mechanical Phenomena ,ATHEROSCLEROTIC PLAQUES ,BIAXIAL MECHANICAL-PROPERTIES ,Isotropy ,Biology and Life Sciences ,Atherosclerosis ,medicine.disease ,020601 biomedical engineering ,MODEL ,Atheroma ,RESOLUTION ,MICROCALCIFICATIONS ,Biomedical engineering - Abstract
The paper deals with the impact of chosen geometric and material factors on maximal stresses in carotid atherosclerotic plaque calculated using patient-specific finite element models. These stresses are believed to be decisive for the plaque vulnerability but all applied models suffer from inaccuracy of input data, especially when obtained in vivo only. One hundred computational models based on ex vivo MRI are used to investigate the impact of wall thickness, MRI slice thickness, lipid core and fibrous tissue stiffness, and media anisotropy on the calculated peak plaque and peak cap stresses. The investigated factors are taken as continuous in the range based on published experimental results, only the impact of anisotropy is evaluated by comparison with a corresponding isotropic model. Design of Experiment concept is applied to assess the statistical significance of these investigated factors representing uncertainties in the input data of the model. The results show that consideration of realistic properties of arterial wall in the model is decisive for the stress evaluation; assignment of properties of fibrous tissue even to media and adventitia layers as done in some studies may induce up to eightfold overestimation of peak stress. The impact of MRI slice thickness may play a key role when local thin fibrous cap is present. Anisotropy of media layer is insignificant, and the stiffness of fibrous tissue and lipid core may become significant in some combinations.
- Published
- 2020