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arXiv · 1407.8196

Imaging of Shear Waves Induced by Lorentz Force in Soft Tissues

Pol Grasland-Mongrain·Rémi Souchon·Florian Cartellier·Ali Zorgani·Jean-Yves Chapelon·Cyril Lafon·Stefan Catheline
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Abstract

This study presents the first observation of elastic shear waves generated in soft solids using a dynamic electromagnetic field. The first and second experiments of this 5 study showed that Lorentz force can induce a displacement in a soft phantom and that this displacement was detectable by an ultrasound scanner using speckle-tracking algorithms. For a 100 mT magnetic field and a 10 ms, 100 mA peak-to-peak electrical burst, the displacement reached a magnitude of 1 um. In the third experiment, we showed that Lorentz force can induce shear waves in a phantom. A physical model 10 using electromagnetic and elasticity equations was proposed. Computer simulations were in good agreement with experimental results. The shear waves induced by Lorentz force were used in the last experiment to estimate the elasticity of a swine liver sample.

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Pol Grasland-Mongrain, Rémi Souchon, Florian Cartellier, Ali Zorgani, Jean-Yves Chapelon, Cyril Lafon, Stefan Catheline. 2014-07-30. Imaging of Shear Waves Induced by Lorentz Force in Soft Tissues. https://doi.org/10.1103/physrevlett.113.038101

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