Print Email Facebook Twitter A Framework for Local Mechanical Characterization of Atherosclerotic Plaques Title A Framework for Local Mechanical Characterization of Atherosclerotic Plaques: Combination of Ultrasound Displacement Imaging and Inverse Finite Element Analysis Author Akyildiz, A.C. (Rensselaer Polytechnic Institute; Erasmus MC) Hansen, Hendrik H.G. (Radboud Universiteit Nijmegen) Nieuwstadt, Harm A. (Erasmus MC) Speelman, Lambert (Erasmus MC) De Korte, Chris L. (Radboud Universiteit Nijmegen) van der Steen, A.F.W. (TU Delft ImPhys/Medical Imaging; TU Delft ImPhys/Acoustical Wavefield Imaging; Erasmus MC) Gijsen, Frank J H (Erasmus MC) Date 2016 Abstract Biomechanical models have the potential to predict plaque rupture. For reliable models, correct material properties of plaque components are a prerequisite. This study presents a new technique, where high resolution ultrasound displacement imaging and inverse finite element (FE) modeling is combined, to estimate material properties of plaque components. Iliac arteries with plaques were excised from 6 atherosclerotic pigs and subjected to an inflation test with pressures ranging from 10 to 120 mmHg. The arteries were imaged with high frequency 40 MHz ultrasound. Deformation maps of the plaques were reconstructed by cross correlation of the ultrasound radiofrequency data. Subsequently, the arteries were perfusion fixed for histology and structural components were identified. The histological data were registered to the ultrasound data to construct FE model of the plaques. Material properties of the arterial wall and the intima of the atherosclerotic plaques were estimated using a grid search method. The computed displacement fields showed good agreement with the measured displacement fields, implying that the FE models were able to capture local inhomogeneities within the plaque. On average, nonlinear stiffening of both the wall and the intima was observed, and the wall of the atheroslcerotic porcine iliac arteries was markedly stiffer than the intima (877 ± 459 vs. 100 ± 68 kPa at 100 mmHg). The large spread in the data further illustrates the wide variation of the material properties. We demonstrated the feasibility of a mixed experimental–numerical framework to determine the material properties of arterial wall and intima of atherosclerotic plaques from intact arteries, and concluded that, due to the observed variation, plaque specific properties are required for accurate stress simulations. Subject Atherosclerotic plaqueInverse methodMaterial propertiesUltrasound To reference this document use: http://resolver.tudelft.nl/uuid:55e09756-705c-46f0-b86f-79305942bc8a DOI https://doi.org/10.1007/s10439-015-1410-8 ISSN 0090-6964 Source Annals of Biomedical Engineering, 44 (4), 968-979 Part of collection Institutional Repository Document type journal article Rights © 2016 A.C. Akyildiz, Hendrik H.G. Hansen, Harm A. Nieuwstadt, Lambert Speelman, Chris L. De Korte, A.F.W. van der Steen, Frank J H Gijsen Files PDF 10.1007_s10439_015_1410_8.pdf 1.57 MB Close viewer /islandora/object/uuid:55e09756-705c-46f0-b86f-79305942bc8a/datastream/OBJ/view