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Title: IMAGING OF FOCUSED ULTRASOUND-INDUCED SHEAR WAVES TO PROBE MECHANICAL ANISOTROPY OF TISSUE
It is important to understand mechanical anisotropy in fibrous soft tissues because of the relationship of anisotropy to tissue function, and because anisotropy may change due to injury and disease. We have developed a method to noninvasively investigate anisotropy, based on MR imaging of harmonic ultrasound-induced motion (MR-HUM), using focused ultrasound (FUS) and magnetic resonance elastography (MRE). MR-HUM produces symmetric, radial waves inside a tissue, which enables a simple assessment of anisotropy using features of the resulting shear wave fields. This method was applied to characterize ex vivo muscle tissue, which is known to exhibit mechanical anisotropy. Finite element (FE) simulations of the experiment were performed to illustrate and validate the approach. Anisotropy was characterized by ratios of apparent shear moduli and strain components in different directions.  more » « less
Award ID(s):
1727412
PAR ID:
10301383
Author(s) / Creator(s):
Date Published:
Journal Name:
Proceedings of the 2021 Design of Medical Devices Conference
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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