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Abstract #0557

Shear Wave Tracking in Cadaveric Breast Using MR-ARFI

MAGNA25R R. Bitton1, E Kaye2, K Butts Pauly1

1Radiology, Stanford University, Stanford, CA, United States; 2Electrical Engineering, Stanford University, Stanford, CA, United States

This study presents an MR-ARFI method that uses two ultrasonic excitations to track the extent of a shear wave, and calculate tissue velocities along radial trajectories in cadaveric breast tissue. The technique was validated using a uniform ARFI phantom and then applied to a cadaveric breast specimen with an ablated subregion. The time-of-flight method was used to calculate the breast tissue velocity along radial trajectories of the displacement map. Breast tissue shear wave velocity ranged from (0.4 6.3) m/s. This technique may be a useful tool in mapping the stiffness of regions within heterogeneous tissue, particularly in MRgHIFU applications.

Keywords

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