A Proof of Concept of a Non-Invasive Image-Based Material Characterization Method for Enhanced Patient-Specific Computational Modeling

• Published in: Cardiovascular engineering and technology Vol. 11; no. 5; pp. 532 - 543
• Main Authors: Fanni, B. M., Sauvage, E., Celi, S., Norman, W., Vignali, E., Landini, L., Schievano, S., Positano, V., Capelli, C.
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.10.2020; Springer Nature B.V
• Subjects: Biomedical Engineering and Bioengineering; Biomedicine; Blood vessels; Blood Vessels - diagnostic imaging; Cardiology; Circulatory system; Elastic deformation; Elastic Modulus; Elastic properties; Engineering; Fluid-structure interaction; Formability; Humans; Image acquisition; Image enhancement; Image Interpretation, Computer-Assisted; Magnetic properties; Magnetic resonance imaging; Magnetic Resonance Imaging - instrumentation; Material properties; Mechanical properties; Models, Cardiovascular; Modulus of elasticity; Original Article; Patient-Specific Modeling; Phantoms, Imaging; Predictive Value of Tests; Printing, Three-Dimensional; Proof of Concept Study; Reproducibility of Results; Tensile Strength; Tensile tests; QA method; Material properties assessment; Mock circulation loop; PC MRI; FSI; 3D printing
• ISSN: 1869-408X; 1869-4098
• DOI: 10.1007/s13239-020-00479-7

Purpose Computational models of cardiovascular structures rely on their accurate mechanical characterization. A validated method able to infer the material properties of patient-specific large vessels is currently lacking. The aim of the present study is to present a technique starting from the flow-area (QA) method to retrieve basic material properties from magnetic resonance (MR) imaging. Methods The proposed method was developed and tested, first, in silico and then in vitro . In silico , fluid-structure interaction (FSI) simulations of flow within a deformable pipe were run with varying elastic modules ( E ) between 0.5 and 32 MPa. The proposed QA-based formulation was assessed and modified based on the FSI results to retrieve E values. In vitro , a compliant phantom connected to a mock circulatory system was tested within MR scanning. Images of the phantom were acquired and post-processed according to the modified formulation to infer E of the phantom. Results of in vitro imaging assessment were verified against standard tensile test. Results In silico results from FSI simulations were used to derive the correction factor to the original formulation based on the geometrical and material characteristics. In vitro , the modified QA-based equation estimated an average E = 0.51 MPa, 2% different from the E derived from tensile tests (i.e. E = 0.50 MPa). Conclusion This study presented promising results of an indirect and non-invasive method to establish elastic properties from solely MR images data, suggesting a potential image-based mechanical characterization of large blood vessels.