Tissue complex modulus and/or viscosity ultrasound imaging
AssigneeSiemens Medical Solutions USA, Inc.
InventorsLiexiang Fan, Paul Freiburger
Life of this patent
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Abstract
Complex response of tissue is calculated as function of a convolution relationship associated with measured strain with applied stress. In the Fourier or frequency domain, the convolution is a simple algebraic computation, such as multiplication. The complex response provides elasticity and viscosity information, assisting diagnosis. Complex compliance may be directly calculated from the strain and stress. Complex fluidity may be directly calculated from strain rate and stress.
Claims12
A method for determining viscoelastic tissue property, the method comprising:
- determining an applied stress, the determining the applied stress comprises identifying an impulse function representing the applied stress;
- measuring, with ultrasound, tissue strain in response to the applied stress;
- and
- determining, with a processor, a complex tissue property as a convolution function of the impulse function of the applied stress and the tissue strain, the impulse function and the tissue strain being variables in the convolution function.
A method for determining viscoelastic tissue property, the method comprising:
- determining an applied stress, wherein determining the applied stress comprises estimating cyclic pressure;
- measuring, with ultrasound, tissue strain in response to the applied stress;
- and
- determining, with a processor, a complex tissue property as a convolution function of variation of the cyclic pressure and tissue strain.
A system for determining viscoelastic tissue property, the system comprising:
- a transducer operable to generate receive signals from received ultrasound energy;
- a receive beamformer operable to output data representing spatial locations along at least a line;
- an image processor operable to determine strain or strain rate as a function of the output data, operable to transform the strain or strain rate into a frequency domain, and operable to calculate elasticity and viscosity tissue properties by algebraic function in the frequency domain, the calculation including a constant based on an impulse function representing acoustic radiation force applied to tissue, the strain or strain rate responsive to the acoustic radiation force.
Dependencies are inferred from the claim text.