Publication detail

Consideration of stiffness of wall layers is decisive for patient-specific analysis of carotid artery with atheroma

LISICKÝ, O. MALÁ, A. BEDNAŘÍK, Z. NOVOTNÝ, T. BURŠA, J.

English title

Consideration of stiffness of wall layers is decisive for patient-specific analysis of carotid artery with atheroma

Type

journal article in Web of Science

Language

en

Original 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 obtainedin vivoonly. One hundred computational models based onex vivoMRI 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.

English 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 obtainedin vivoonly. One hundred computational models based onex vivoMRI 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.

Keywords in English

BIAXIAL MECHANICAL-PROPERTIES; FIBROUS CAP THICKNESS; IN-VIVO; ATHEROSCLEROTIC PLAQUES; STRESS; MODEL; MICROCALCIFICATIONS; RESOLUTION; STRAIN; INTACT

Released

29.09.2020

Publisher

PLOS

ISSN

1932-6203

Volume

15

Number

9

Pages from–to

1–18

Pages count

18

BIBTEX


@article{BUT165769,
  author="Ondřej {Lisický} and Jiří {Vaverka} and Aneta {Malá} and Zdeněk {Bednařík} and Tomáš {Novotný} and Jiří {Burša},
  title="Consideration of stiffness of wall layers is decisive for patient-specific analysis of carotid artery with atheroma",
  year="2020",
  volume="15",
  number="9",
  month="September",
  pages="1--18",
  publisher="PLOS",
  issn="1932-6203"
}