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Dynamic elastography, whether based on magnetic resonance, ultrasound, or optical modalities, attempts to reconstruct quantitative maps of the viscoelastic properties of biological tissue, properties that are altered by disease and injury, by noninvasively measuring mechanical wave motion in the tissue. Most reconstruction strategies that have been developed neglect boundary conditions, including quasistatic tensile or compressive loading resulting in a nonzero prestress. Significant prestress is inherent to the functional role of some biological tissues currently being studied using elastography, such as skeletal and cardiac muscle, arterial walls, and the cornea. In the present article, we review how prestress alters both bulk mechanical wave motion and wave motion in one- and two-dimensional waveguides. Key findings are linked to studies on skeletal muscle and the human cornea, as one- and two-dimensional waveguide examples. This study highlights the underappreciated combined acoustoelastic and waveguide challenge to elastography. Can elastography truly determine viscoelastic properties of a material when what it is measuring is affected by both these material properties and unknown prestress and other boundary conditions?
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Harmonic Elastography Through Time-of-Flight Calculations
This work addresses the IUS challenge focused on assessing the accuracy of various methods in providing elastography images of soft tissue using shear wave elastography (SWE) data, specifically from harmonic excitation. The challenge is not necessarily aimed at developing new methodologies but applying existing (or new) methodologies to assess their accuracy. In this spirit, we illustrate that simple time-of-flight calculations can provide useful first-order-approximate reconstruction of the underlying structure.
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- Award ID(s):
- 2111234
- PAR ID:
- 10659427
- Publisher / Repository:
- 2024 IEEE Ultrasonics, Ferroelectrics, and Frequency Control Joint Symposium (UFFC-JS)
- Date Published:
- Format(s):
- Medium: X
- Location:
- Taipei, Taiwan
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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