Radiation force of ultrasound as shear wave source in Microscopic Magnetic Resonance Elastography

Date

2005-10-21

Author

Özer, Mehmet Bülent
Xu, Huıhuı
Meral, Can
Royston, Thomas J
Magın, Rıchard L

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Microscopic magnetic resonance elastography (micro‐MRE) is a high‐resolution imaging technique for measuring the viscoelastic properties of small synthetic and biological samples. Taking MRE to the microscopic scale requires stronger static fields, stronger magnetic field gradients, higher performance RF coils, and more compact, higher frequency shear wave actuators. Prior work by our group has been conducted at 11.74 T. A needle attached to a vibrating cantilever beam was placed in contact with the surface of the sample to generate shear waves up to 800 Hz. At higher frequencies, the excited shear waves attenuate within an extremely short distance such that only a very small region in the vicinity of the actuator can be studied due to inherent dynamic range limitations. In principle, modulated focused radiation force of US should be able to create a localized shear wave source within the test sample at a distance from the US transducer, thereby enabling micro‐MRE probing of the sample at very high frequencies (up to 5 kHz). A confocal US transducer was fabricated to create such a source within the working constraints of the micro‐MRE system. Initial feasibility studies are reviewed in this presentation.

URI

https://hdl.handle.net/11511/74325

Conference Name

150th Meeting of the Acoustical Society of America, 17 - 21 Ekim 2005

Collections

Department of Mechanical Engineering, Conference / Seminar

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Citation Formats

M. B. Özer, H. Xu, C. Meral, T. J. Royston, and R. L. Magın, “Radiation force of ultrasound as shear wave source in Microscopic Magnetic Resonance Elastography,” presented at the 150th Meeting of the Acoustical Society of America, 17 - 21 Ekim 2005, 2005, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/74325.