Material properties estimation of layered soft tissue based on MR observation and iterative FE simulation

Area of Science:

• Biomechanics
• Medical Imaging
• Materials Science

Background:

• Accurate soft tissue deformation calculation requires considering non-linear material properties and complex subcutaneous structures.
• Existing methods often struggle to integrate these factors effectively.

Purpose of the Study:

• To develop and validate a method for estimating soft tissue material properties.
• To account for non-linear material behavior and layered anatomical structures in deformation analysis.

Main Methods:

• Utilizing in-situ compression tests within Magnetic Resonance Imaging (MRI) to visualize tissue deformation.
• Developing a finite element (FE) model incorporating a non-linear material model for the compressed tissue.
• Iteratively updating FE material constants to minimize discrepancies between observed and calculated displacement fields.

Main Results:

• The method was successfully applied to a 3-layered silicon rubber phantom.
• Achieved estimation accuracy better than 15%.
• Demonstrated high reproducibility of deformation measurements, with errors less than 0.4 mm.

Conclusions:

• The presented method effectively estimates soft tissue properties by integrating MRI visualization and FE analysis.
• This approach offers a robust solution for calculating soft tissue deformation under various loading conditions.
• The validated accuracy and reproducibility highlight its potential for biomechanical applications.